CN112825463A - Voltage-reduction chopper type direct current motor driving device and electric equipment - Google Patents
Voltage-reduction chopper type direct current motor driving device and electric equipment Download PDFInfo
- Publication number
- CN112825463A CN112825463A CN201911119445.0A CN201911119445A CN112825463A CN 112825463 A CN112825463 A CN 112825463A CN 201911119445 A CN201911119445 A CN 201911119445A CN 112825463 A CN112825463 A CN 112825463A
- Authority
- CN
- China
- Prior art keywords
- power supply
- bridge arm
- motor driving
- chopper
- terminals
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 239000003990 capacitor Substances 0.000 claims abstract description 19
- 238000004804 winding Methods 0.000 claims description 16
- 238000010168 coupling process Methods 0.000 claims description 5
- 230000010363 phase shift Effects 0.000 claims description 5
- 230000008878 coupling Effects 0.000 claims description 3
- 238000005859 coupling reaction Methods 0.000 claims description 3
- 230000005685 electric field effect Effects 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 23
- 230000005284 excitation Effects 0.000 description 12
- 238000000034 method Methods 0.000 description 12
- 230000008569 process Effects 0.000 description 12
- 239000000696 magnetic material Substances 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000006073 displacement reaction Methods 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 229910001004 magnetic alloy Inorganic materials 0.000 description 2
- 230000002035 prolonged effect Effects 0.000 description 2
- WBWJXRJARNTNBL-UHFFFAOYSA-N [Fe].[Cr].[Co] Chemical compound [Fe].[Cr].[Co] WBWJXRJARNTNBL-UHFFFAOYSA-N 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 229910000828 alnico Inorganic materials 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 230000008094 contradictory effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P7/00—Arrangements for regulating or controlling the speed or torque of electric DC motors
- H02P7/06—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current
- H02P7/18—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power
- H02P7/24—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices
- H02P7/28—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices
- H02P7/285—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices controlling armature supply only
- H02P7/292—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices controlling armature supply only using static converters, e.g. AC to DC
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/14—Arrangements for reducing ripples from dc input or output
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
- H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
- H02M3/10—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P7/00—Arrangements for regulating or controlling the speed or torque of electric DC motors
- H02P7/06—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current
- H02P7/18—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power
- H02P7/24—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices
- H02P7/28—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices
- H02P7/285—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices controlling armature supply only
- H02P7/29—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices controlling armature supply only using pulse modulation
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Direct Current Motors (AREA)
Abstract
The invention provides a step-down chopper type direct current motor driving device and electric equipment. The direct current motor driving device includes: a direct current motor; a DC power supply unit; the buck chopper comprises m chopper units, each chopper unit comprises an upper bridge arm, a lower bridge arm, a first power supply output end and a second power supply output end, each upper bridge arm comprises at least one power switching tube, at least one capacitor, at least one inductor and a switch control end, each control signal comprises m switch control signals which correspond to the m chopper units respectively and are formed according to a preset phase staggering rule, each switch control end is used for correspondingly receiving the corresponding switch control signal, each lower bridge arm comprises at least one diode, the first power supply output end is arranged between the upper bridge arm and the corresponding lower bridge arm, and the second power supply output end is arranged at the end part, connected with the direct-current power supply part, of the corresponding lower bridge arm.
Description
Technical Field
The invention belongs to the field of direct current motor driving devices, and particularly relates to a voltage-reducing chopper type direct current motor driving device and electric equipment comprising the same.
Background
The direct current motor has the advantages of small volume, high efficiency, simple structure, convenient speed regulation by changing the armature voltage and the like, and is widely applied to electric equipment such as electric automobiles, electric bicycles, artillery, tanks, radars and the like. As shown in fig. 8, a conventional dc motor driving device 200 is composed of a dc motor, a chopper, a dc power supply, and a control unit.
However, the conventional dc motor driving apparatus 200 has the following drawbacks: 1) the chopper adopts the pulse width modulation technology to control the on and off of the power switch tube, so as to change the output voltage and the output current, therefore, the size of the output current ripple is in direct proportion to the output torque of the direct current motor and the size of the rotating speed ripple, and is in inverse proportion to the switching frequency of the power switch tube. Because the switching loss (or temperature rise and failure rate) of the power switching tube is in direct proportion to the switching frequency of the power switching tube, in order to reduce the ripple size of the output torque and the rotating speed of the direct current motor, the switching frequency of the power switching tube must be increased; when the switching frequency of the power switching tube is increased, the switching loss of the power switching tube is increased, so that the power switching tube is easily damaged, and further, the integral failure or short circuit and other faults of the chopper are caused. This contradictory relationship hinders the development of the dc motor driving apparatus, which makes it difficult to apply the dc motor driving apparatus to the electric equipment having strict requirements on the rotational speed and torque ripple of the motor. 2) In the conventional dc motor driving apparatus 200, the maximum output current of the chopper is generally 2 to 3 times of the rated current of the dc motor, and the actual operating current of the chopper used in the high-power dc motor, especially the low-voltage high-current dc motor, often reaches several hundred amperes or even thousands of amperes. However, commercially available choppers typically have a maximum output current of less than one thousand amperes and the power switching tubes that can be used in choppers for high power dc motors are expensive, resulting in a chopper with an excessive manufacturing cost. 3) In the conventional dc motor driving apparatus 200, the dc motor has only one pair of external connection terminals electrically connected to the power output terminal of the chopper, and thus when the brush or the connection line between the dc motor and the chopper fails, the dc motor is liable to be suddenly out of control, which may cause a failure of the electric device or even a safety accident.
Disclosure of Invention
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a step-down chopper type dc motor driving device and an electric apparatus including the same.
In order to achieve the purpose, the invention adopts the following technical scheme:
< Structure I >
The invention provides a voltage-reducing chopper type direct current motor driving device, which comprises: a DC motor having a rated voltage; a DC power supply unit having a constant voltage corresponding to a rated voltage; and a step-down chopper which converts a constant voltage into a variable voltage based on a control signal and supplies the variable voltage to the DC motor, wherein the step-down chopper has m chopper units each including an upper arm and a lower arm connected in series with each other, the upper arm being connected to a positive electrode of the DC power supply portion, the lower arm being connected to a negative electrode of the DC power supply portion, the upper arm including at least one power switching tube, at least one capacitor, at least one inductor, and a switching control terminal, the power switching tube being connected in series with the inductor, each power switching tube having a control electrode, the switching control terminal being formed based on the control electrode, the control signal including m switching control signals which correspond to the m chopper units respectively and are formed in accordance with a predetermined phase-staggered rule, the switch control end is used for correspondingly receiving a switch control signal, the lower bridge arm comprises at least one diode, the first power supply output end is arranged between the upper bridge arm and the lower bridge arm, the second power supply output end is arranged at the end part of the lower bridge arm connected with the direct-current power supply part, m pairs of power supply output terminals are respectively and correspondingly formed by the m first power supply output ends of all chopping units and the m second power supply output ends of all chopping units, and the direct-current motor comprises: a housing; m pairs of electric brushes fixed in the machine shell; the stator is arranged in the machine shell and comprises m pairs of main magnetic poles corresponding to the m pairs of electric brushes; the rotor is arranged in the stator and comprises a plurality of armature windings which are mutually connected in a preset connection mode, each pair of main magnetic poles comprises an S-polarity main magnetic pole and an N-polarity main magnetic pole which are adjacent, two electric brushes in each pair of electric brushes are adjacent in position, each pair of electric brushes comprises an S-pole corresponding electric brush corresponding to the S-polarity main magnetic pole and an N-pole corresponding electric brush corresponding to the N-polarity main magnetic pole, leading-out ends of all the S-poles corresponding to the electric brushes form m first terminals, and leading-out ends of all the N-poles corresponding to the electric brushes form m second terminals; or all N poles correspond to leading-out ends of the electric brushes to form m first wiring ends, all S poles correspond to leading-out ends of the electric brushes to form m second wiring ends, the m first wiring ends and the m second wiring ends respectively and correspondingly form m pairs of external wiring terminals, the m pairs of external wiring terminals are connected with the m pairs of power output terminals in a one-to-one correspondence mode, and m is a positive integer not less than 2.
The step-down chopper type dc motor driving apparatus according to the present invention may further include: the switching frequency fs of the power switching tube in each chopper unit, the inductance value Lr of the inductor and the capacitance value Cr of the capacitor satisfy the following relations:
the step-down chopper type dc motor driving apparatus according to the present invention may further include: the preset phase staggering rule is that the phases of the m switch control signals are staggered by m times of a switch period respectively; alternatively, m is an even number, and the predetermined phase shift rule is such that the phases of the m switching control signals are sequentially shifted by m-two switching periods, respectively.
The step-down chopper type dc motor driving apparatus according to the present invention may further include: and the control part comprises a controller and an amplifier, wherein the controller generates m switch control signals according to a preset phase staggering rule, and the amplifier amplifies the m switch control signals and correspondingly provides the m switch control signals to m switch control terminals.
The step-down chopper type dc motor driving apparatus according to the present invention may further include: the amplifier is composed of m independent amplifying units, the m amplifying units correspond to the m chopping units respectively, and each amplifying unit is provided with an amplifying signal output end correspondingly connected with the switch control end.
The step-down chopper type dc motor driving apparatus according to the present invention may further include: wherein, the upper bridge arm comprises a power switch tube, and when all the power switch tubes have the same maximum output current I1Maximum of DC motorCurrent is ImaxWhen m satisfies the following condition: m is more than 1.1 (I)max÷I1) (ii) a Or the upper bridge arm comprises p power switch tubes which are connected in parallel, and when all the power switch tubes have the same maximum output current I1The maximum current of the DC motor is ImaxM satisfies the following condition: m is more than 1.1 (I)max÷(k×p×I1) P is a positive integer not less than 2, k is a parallel coefficient, 1/p<k<1。
The step-down chopper type dc motor driving apparatus according to the present invention may further include: wherein the predetermined coupling means is any one of a single stack, a multiple stack and a complex wave.
The step-down chopper type dc motor driving apparatus according to the present invention may further include: the power switch tube is a semi-control device or a full-control device, the semi-control device is a common thyristor, and the full-control device is any one of an electric field effect transistor, a gate turn-off thyristor, an integrated gate commutation thyristor, an insulated gate bipolar transistor and an electric power bipolar transistor.
< Structure two >
The present invention also provides an electrically powered device comprising: the step-down chopper type direct current motor driving device is a step-down chopper type direct current motor driving device of the structure I.
The electric device provided by the present invention may further have the following features: wherein, the electrical equipment is any one of electric automobile, electric bicycle, artillery, tank and radar.
Action and Effect of the invention
Compared with the prior art, the step-down chopper type direct current motor driving device and the electric equipment comprising the same have the following advantages:
1) because the buck chopper has m chopper units, each chopper unit comprises an upper bridge arm and a lower bridge arm, and a first power output end and a second power output end, the upper bridge arm and the lower bridge arm are connected in series, the upper bridge arm is connected with the positive pole of the direct-current power supply part, the lower bridge arm is connected with the negative pole of the direct-current power supply part, the upper bridge arm comprises at least one power switching tube, at least one capacitor, at least one inductor and a switch control end, each power switching tube has a control pole, the switch control end is formed based on the control pole, the lower bridge arm comprises at least one diode, the first power output end is arranged between the upper bridge arm and the lower bridge arm, the second power output end is arranged at the end part where the lower bridge arm is connected with the direct-current power supply part, the m first power output ends of all chopper units and the m second power output ends of all chopper units respectively form m pairs of power output, leading-out ends of all S poles corresponding to the electric brushes form m first wiring ends, and leading-out ends of all N poles corresponding to the electric brushes form m second wiring ends; or, the leading-out ends of the brushes corresponding to all the N poles form m first wiring terminals, the leading-out ends of the brushes corresponding to all the S poles form m second wiring terminals, the m first wiring terminals and the m second wiring terminals respectively form m pairs of external wiring terminals correspondingly, and the m pairs of external wiring terminals are connected with the m pairs of power output terminals in a one-to-one correspondence manner, so that the invention can realize m pairs of mutually independent brushes on the basis of not changing the rotor structure of the traditional direct current motor, and the armature branch formed by each pair of brushes is independently supplied with power by the corresponding chopping unit, namely, each chopping unit only bears the working current of one armature branch, and the output current of each chopping unit is only one m-fold of the rated input current of the direct current motor, so that the step-down chopping chopper can meet the requirement of the high-power direct current motor by using the common power switching tube without adopting a power module or a parallel current sharing technology, and the manufacturing cost of the step-down chopper is further reduced, and the requirements of a connecting wire and a connecting piece between the step-down chopper and the direct current motor on contact resistance and insulation are reduced, so that the manufacturing cost of the step-down chopper direct current motor driving device is greatly reduced.
2) Because the upper bridge arm comprises at least one power switch tube, at least one capacitor, at least one inductor and a switch control end, the power switch tube is connected with the inductor in series, and the lower bridge arm comprises at least one diode, the buck chopper can realize that the power switch tube works in a zero-current soft switching state in the conducting process and the turning-off process by using the inductor and the capacitor with low cost for control, so that the switching loss of the power switch tube is greatly reduced, the heat productivity and the temperature rise of the buck chopper are greatly reduced, the fault rate of the buck chopper is reduced, the service life of the buck chopper is prolonged, and the reliability and the safety of the buck chopper direct-current motor driving device are improved.
3) Because the control signal comprises m switch control signals which are respectively corresponding to the m chopping units and are formed according to the preset phase staggering rule, and the switch control end in each chopping unit correspondingly receives the switch control signals, the phases of the output current ripples of each chopping unit are different, so that the ripple coefficient of the output current ripples of the m chopping units after being superposed is reduced, the ripple coefficient of the output torque and the rotating speed of the direct current motor is further reduced, the electromagnetic interference, vibration and noise of the direct current motor are greatly reduced, and the performance and the service life of the buck chopping type direct current motor driving device are improved.
4) Because m pairs of electric brushes are mutually independent, and the armature branch formed by each pair of electric brushes is independently supplied with power by the corresponding chopping unit, when a connecting line between one electric brush, the armature branch and the corresponding chopping unit has a fault, only the part where the fault is located needs to be shielded, and other normal parts can still work, so that the phenomenon of sudden runaway of the traditional direct current motor under the fault condition can be avoided, and the reliability and the safety of the voltage-reducing chopping direct current motor driving device are improved.
Drawings
FIG. 1 is a schematic circuit diagram of a buck chopper type DC motor driving apparatus according to an embodiment of the present invention;
fig. 2 is a circuit connection diagram of the step-down chopper type dc motor driving apparatus in the state where m is 3 according to the embodiment of the present invention;
fig. 3 is a schematic longitudinal cross-sectional view of a dc motor according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of a cross-sectional electrical connection of a DC motor according to an embodiment of the present invention;
fig. 5 is a schematic diagram illustrating the development of a single-lap joint of armature windings of a dc motor according to an embodiment of the present invention;
FIG. 6 is a waveform diagram of a chopper unit in an embodiment of the present invention;
fig. 7 is a waveform comparison diagram of a dc motor according to an embodiment of the present invention and a conventional dc motor;
fig. 8 is a schematic circuit connection diagram of a conventional dc motor driving apparatus.
Detailed Description
The following describes embodiments of the present invention with reference to the drawings.
< example >
FIG. 1 is a schematic circuit diagram of a buck chopper type DC motor driving apparatus according to an embodiment of the present invention; fig. 2 is a circuit connection diagram of the step-down chopper type dc motor driving apparatus in the state where m is 3 according to the embodiment of the present invention.
As shown in fig. 1 and 2, the step-down chopper type dc motor driving apparatus 100 in the present embodiment is provided in an electric device such as an electric automobile, an electric bicycle, a gun, a tank, and a radar, and drives the electric device. The step-down chopper type dc motor driving apparatus 100 includes a dc motor 10, a step-down chopper 20, a dc power supply unit 30, a sensor unit 40, and a control unit 50.
Fig. 3 is a schematic longitudinal cross-sectional view of a dc motor according to an embodiment of the present invention; fig. 4 is a schematic diagram of a transverse cross-sectional circuit connection of the dc motor according to the embodiment of the present invention.
As shown in fig. 1 to 4, the dc motor 10 has a rated voltage and a rated current, and includes a housing 11, a stator 12, a brush 13, a rotor 14, and a terminal block (not shown). As shown in fig. 1, the logarithm of the brushes 13 is set to m, which is an integer not less than 2, according to the value of the rated current. As shown in fig. 2 and 4, m is set to 3 in the present embodiment.
As shown in fig. 1 to 4, the stator 12 is disposed in the casing 11 and includes m pairs of main poles 121. In this embodiment, as shown in fig. 4, the stator 12 includes 3 pairs of 6 main poles 121.
Each pair of main poles 121 includes an S-polarity main pole 1211 and an N-polarity main pole 1212. Of all the main poles 121, the polarities of the adjacent two main poles 121 are opposite.
Each pair of main magnetic poles 121 includes a permanent magnetic material (not shown), which may be an alnico permanent magnetic alloy, an iron-chromium-cobalt permanent magnetic alloy, a permanent magnetic ferrite, a rare earth permanent magnetic material, a composite permanent magnetic material, etc., and the permanent magnetic material forms an S-polarity main magnetic pole 1211 and an N-polarity main magnetic pole 1212 in each pair of main magnetic poles 121, which can improve the efficiency of the dc motor 10 and save electric energy; or, the stator includes at least one excitation winding part, each excitation winding part includes at least one excitation winding unit, each excitation winding unit is formed by making an excitation coil on at least one pair of main poles through an insulated conductor bar formed by metal wires wrapped with an insulating layer, the excitation coil forms an S-polarity main pole 1211 and an N-polarity main pole 1212 on the main poles, and the excitation mode of the excitation winding part in the dc motor is any one of separate excitation, series excitation, parallel-series excitation and series-parallel excitation. In this embodiment, the S-polarity main pole 1211 and the N-polarity main pole 1212 are excited by a permanent magnetic material.
As shown in fig. 1 to 4, m pairs of brushes 13 are fixedly disposed in the casing 11 and respectively correspond to the m pairs of main poles 121. In the present embodiment, as shown in fig. 2 and 4, the number of the brushes 13 is 6 in total for 3 pairs.
Each pair of brushes 13 includes an S-pole corresponding brush 131 corresponding to the S-polarity main pole 1211 and an N-pole corresponding brush 132 corresponding to the N-polarity main pole 1212. The 2 brushes 13 in each pair of brushes 13 are located adjacently; also, each pair of brushes 13 corresponds to a spatial position of each corresponding pair of main magnetic poles 121, so that a maximum torque can be generated.
The brush 13 is any one of a narrow brush and a wide brush, and the brush 13 is a narrow brush in the present embodiment. Each brush 13 comprises one brush body or at least two separately shaped brush bodies arranged axially of the machine and electrically connected in parallel; when the brush 13 includes at least two brush bodies, the actual contact area of each brush with the commutator can be increased, thereby improving the commutation performance of the brush. As shown in fig. 2 to 4, the brush 13 of the present embodiment includes a brush body.
As shown in fig. 1, two terminals of each pair of brushes 13 form a first terminal 1511 and a second terminal 1512, respectively, and m first terminals 1511 and m second terminals 1512 of all brushes 13 form m pairs of external connection terminals 151, respectively, correspondingly.
In this embodiment, as shown in fig. 2 and 4, the first terminal 1511 and the second terminal 1512 form 1-pair external connection terminals 151, the first terminal 1521 and the second terminal 1522 form 1-pair external connection terminals 152, and the first terminal 1531 and the second terminal 1532 form 1-pair wiring terminals 153.
Fig. 5 is a schematic diagram of the development of the armature winding of the dc motor according to the embodiment of the present invention.
As shown in fig. 1 to 4, the rotor 14 is disposed in the stator 12, and includes a plurality of armature windings 141 coupled to each other by a predetermined coupling method, the number of the armature windings 141 is set to 2m × n, and the predetermined coupling method is any one of a single-winding, a multiple-winding, and a complex wave. In this embodiment, as shown in fig. 5, the plurality of armature windings 141 are connected in a single-layer manner, and two adjacent brushes 13 are connected to one armature winding branch, each of which contains n armature windings 141.
A junction box (not shown) is fixed to the cabinet 11, and 3 pairs of external connection terminals 151, 152 and 153 are provided in the junction box as shown in fig. 2 and 4.
As shown in fig. 1, the step-down chopper 20 converts a constant voltage of the dc power supply unit 30 into a variable voltage whose average voltage is controlled based on a control signal from the control unit 50, and supplies the variable voltage to the dc motor 10. The step-down chopper 20 includes m chopper units 21 corresponding to the m pairs of brushes 13, respectively. In the present embodiment, as shown in fig. 2, the step-down chopper 20 includes 3 chopper units 21.
Each chopper unit 21 includes an upper arm 211 and a lower arm 212 connected in series with each other, and a first power supply output terminal 2211 and a second power supply output terminal 2212.
The upper arm 211 includes a power switch tube 2111, an inductor 2112, a capacitor 2113, and a switch control terminal 2110. The power switch 2111 is connected in series with the inductor 2112 and in parallel with the capacitor 2113, the power switch 2111 having a control terminal forming the switch control terminal 2110. In this embodiment, in order to improve the safety of the power switch tube 2111 in actual operation, the switching frequency fs of the power switch tube 2111, the inductance Lr of the inductor 2112, and the capacitance Cr of the capacitor 2113 in each chopper unit 21 satisfy the following relationship:
when all the power switch tubes 2111 have the same maximum output current I1The maximum current of the DC motor 10 is ImaxWhen m satisfies the following condition: m is more than 1.1 (I)max÷I1). The maximum output current is an important parameter of the power switch tube, the power switch tube can stably operate only under the current value, and if the working current exceeds the current value, the power switch tube is broken down due to overcurrent, so that the power switch tube is damaged.
In this embodiment, all the power switching transistors are half-control type devices or full-control type devices, the half-control type devices are ordinary thyristors, and the full-control type devices are any one of electric field effect transistors, gate turn-off thyristors, integrated gate commutated thyristors, insulated gate bipolar transistors and electric power bipolar transistors.
The lower leg 212 includes a freewheeling diode 2121.
As shown in fig. 1, first power supply output terminal 2211 is provided between upper arm 211 and lower arm 212, and second power supply output terminal 2212 is provided at the end of lower arm 211 connected to dc power supply unit 30. The m first power supply outputs 2211 of all the chopper units 21 and the m second power supply outputs 2212 of all the chopper units 21 respectively form m pairs of power supply output terminals 221, and the m pairs of power supply output terminals 221 and the m pairs of external connection terminals 151 are connected in one-to-one correspondence.
In this embodiment, as shown in fig. 2, the first power output 2211 and the second power output 2212 form 1 pair of power output terminals 221, the first power output 2221 and the second power output 2222 form 1 pair of power output terminals 222, the first power output 2231 and the second power output 2232 form 1 pair of power output terminals 223, 3 pairs of power output terminals 221, 222 and 223, and 3 pairs of external connection terminals 151, 152 and 153, which are connected in a one-to-one correspondence.
As shown in fig. 1 and 2, the dc power supply unit 30 has a constant voltage corresponding to the rated voltage of the dc motor 10, and has m pairs of power supply output terminals connected to the m chopper units 21 in one-to-one correspondence. Each pair of power supply output terminals includes a positive electrode 311 and a negative electrode 312, the positive electrode 311 is connected to the upper arm 211 in the corresponding chopper unit 21, and the negative electrode 312 is connected to the lower arm 212 in the corresponding chopper unit 21.
As shown in fig. 1 and 2, the sensor unit 40 detects a physical quantity of the dc motor 10 and outputs a feedback signal to the control unit 50. The sensing unit 40 includes an output sensor 41 and a current sensor 42.
The output sensor 41 detects the displacement, the rotational speed, or the torque output from the dc motor 10 and outputs a corresponding output feedback signal to the control unit 50.
The current sensor 42 detects a line current value of a brush lead-out wire in the dc motor 10 and outputs a corresponding current feedback signal to the control unit 50.
As shown in fig. 1 and 2, the control unit 50 receives an external command signal corresponding to the displacement, the rotational speed, or the torque output from the dc motor 10. The control section 50 includes a controller 51 and an amplifier 52.
The controller 51 generates and outputs a control signal 511 and an enable signal 512 to the amplifier 52 by calculation based on the external command signal and the output feedback signal and the current feedback signal of the sensing part 40. The control signal 511 contains m switching control signals respectively corresponding to the m chopper units 21 and formed in accordance with a predetermined phase shift rule, and the enable signal 512 is used to control the operating state of the amplifier 52.
The amplifier 52 enters an operating state under the control of the enable signal 512, amplifies the m switch control signals and provides them to the m switch control terminals 2110. The amplifier 52 has m amplified signal output terminals 521 corresponding to the m chopper units 21, respectively, and the m amplified signal output terminals 521 are connected to the m switch control terminals 2110 in a one-to-one correspondence.
In this embodiment, the predetermined phase staggering rule is that the phases of m switching control signals are staggered by m times of the switching period in sequence, so that ripple peak-to-peak values of current ripples of output currents of power output terminals of m chopper units after being superimposed are reduced, thereby reducing peak-to-peak values of ripples of output torque and rotation speed, and further improving the performance and the service life of the dc motor. Of course, when m is an even number, the predetermined phase staggering rule is that the phases of m switch control signals are staggered by two m-th of the switching period in sequence respectively, so that current ripples of output currents of power supply output terminals of every two chopper units corresponding to every two pairs of brushes which are opposite in space are the same, a couple moment is generated in the motor, friction moment between a shaft and a bearing caused by the fact that the couple moment cannot be formed by the output torque ripples of the motor is avoided, abrasion between the shaft and the bearing is reduced, and the performance and the service life of the direct current motor are improved.
Fig. 6 is a waveform diagram of a chopper unit in an embodiment of the present invention.
As shown in fig. 6, a waveform diagram corresponding to Vpwm1 is a voltage waveform diagram of the switching control signal in the embodiment of the present invention shown in fig. 2, a waveform diagram corresponding to I (Lr1) is a current waveform diagram of inductor 2112, a waveform diagram corresponding to V (Cr1) is a voltage waveform diagram of capacitor 2113, a waveform diagram corresponding to V (Q1) is a voltage waveform diagram of power switch 2111, and a waveform diagram corresponding to I1 is an output current waveform diagram of chopper unit 21. The switching control signal and the switching frequency of the power switch 2111 are both 1 khz for example, and the description will be given below.
Because the current value of the power switch tube 2111 is equal to zero when the waveform of the switching control signal is changed from high level to low level or from low level to high level, that is, the switching loss of the power switch tube 2111 in the conducting process and the switching-off process is equal to zero, the embodiment can realize that the power switch tube works in a zero-current soft switching state in the conducting process and the switching-off process, avoid the problem that the power switch tube in the traditional chopper generates serious switching loss in the conducting process and the switching-off process, greatly reduce the heat productivity and temperature rise of the buck chopper, further reduce the fault rate of the buck chopper, improve the service life of the buck chopper, and further improve the reliability and safety of the buck chopper direct current motor driving device.
In addition, the current waveform of the inductor 2112 and the voltage waveform of the capacitor 2113 are partially in a resonant state, and when the inductance value of the inductor 2112 is set to Lr and the capacitance value of the capacitor 2113 is set to Cr, the formula is given
The calculated resonant frequency of the power switch tube 2111 and the calculated resonant frequency of the power switch tube 2111 are both about 2.5 kilohertz and are both greater than 1.1 times of the switching frequency fs of the power switch tube 2111, so that the power switch tube 2111 can be effectively ensured to work in a zero-current soft switching state in the on process and the off process. The current of the inductor 2112 and the voltage of the capacitor 2113 are continuously changed, and the partial waveform is in a resonance state all the time, and the forward voltage of the power switch tube 2111 before conduction is less than zero, so the current of the power switch tube 2111 during conduction is zero, and is in a zero-voltage soft switching state at this time, and the output current waveform of the chopper unit 21 is smooth.
In actual operation of the step-down chopper, although the voltage waveform of the power switching tube 2111 is intermittent, the output current of the chopper unit 21 is always continuous and smooth.
Fig. 7 is a waveform comparison diagram of the dc motor according to the embodiment of the present invention and the conventional dc motor.
As shown in fig. 7, Ia1, Ia2, and Ia3 are currents flowing through three brushes a1, a2, and A3 of the dc motor 10 of the present embodiment, respectively; ia10, Tem10, and n10 are the armature current, the electromagnetic torque, and the rotation speed of the dc motor 10 of the present embodiment, respectively, and Ia10 is Ia1+ Ia2+ Ia 3; ia200, Tem200, and n200 are the armature current, electromagnetic torque, and rotational speed, respectively, of a conventional dc motor. The following description will be made by taking, as an example, a state in which the dc motor driving device of the present embodiment and the conventional dc motor driving device are all in the same load, switching frequency, and motor rating parameters. Wherein the switching frequency is 1 khz.
In a steady state, the peak-to-peak value of the ripple is the difference between the maximum value and the minimum value, and the ripple coefficient is the percentage of the peak-to-peak value and the average value.
Since the phases of the three switching control signals are sequentially shifted by 3 switching periods under the predetermined phase shift rule, the currents Ia1, Ia2 and Ia3 of the three brushes a1, a2 and A3 are equal in amplitude and sequentially shifted by 3 switching periods, respectively, and the waveform is smooth. Although the average values of the armature current Ia10, the electromagnetic torque Tem10, and the rotation speed n10 of the dc motor 10 of the present embodiment are substantially equal to the average values of the armature current Ia200, the electromagnetic torque Tem200, and the rotation speed n200 of the conventional dc motor, respectively, the ripple coefficients of the currents Ia1, Ia2, and Ia3 of the three brushes a1, a2, and A3 of the dc motor 10 of the present embodiment are all about 1 time the ripple coefficient of the armature current Ia200 of the conventional dc motor, however, the ripple coefficients of the armature current Ia10 and the electromagnetic torque Tem10 of the dc motor 10 of the present embodiment are about 18 times the ripple coefficient of the armature current Ia200 and the electromagnetic torque Tem200 of the conventional dc motor, respectively, and the ripple coefficient of the rotation speed n10 of the dc motor 10 of the present embodiment is about 50 times the ripple coefficient of the rotation speed n200 of the conventional dc motor, so that the electromagnetic interference, vibration, and noise of the dc motor 10 are greatly reduced, thereby improving the performance and life of the dc motor driving apparatus 100.
Examples effects and effects
According to the step-down chopper type dc motor driving device and the electric apparatus including the step-down chopper type dc motor driving device according to the present embodiment, since the step-down chopper has m chopper units, each chopper unit includes an upper arm and a lower arm connected in series with each other, the upper arm is connected to the positive electrode of the dc power supply unit, the lower arm is connected to the negative electrode of the dc power supply unit, the upper arm includes a power switching tube, a capacitor, an inductor, and a switching control terminal, each power switching tube has a control terminal formed based on the control terminal, the lower arm includes a diode, the first power supply output terminal is provided between the upper arm and the lower arm, the second power supply output terminal is provided at the end of the lower arm connected to the dc power supply unit, m pairs of power supply output terminals are respectively and correspondingly formed by the m first power supply output terminals of all the chopping units and the m second power supply output terminals of all the chopping units, m first wiring terminals are formed by leading-out terminals of the electric brushes corresponding to all the S poles, and m second wiring terminals are formed by leading-out terminals of the electric brushes corresponding to all the N poles; or, m first terminals are formed at the leading-out ends of the brushes corresponding to all the N poles, m second terminals are formed at the leading-out ends of the brushes corresponding to all the S poles, m pairs of external terminals are formed at the m first terminals and the m second terminals respectively corresponding to the m pairs of external terminals, and the m pairs of external terminals are connected with the m pairs of power output terminals in a one-to-one correspondence manner, so that the embodiment can realize m pairs of independent brushes on the basis of not changing the structure of the rotor of the traditional direct current motor, and the armature branch formed by each pair of brushes is independently supplied with power by the corresponding chopper unit, that is, each chopper unit only bears the working current of one armature branch, and the output current of each chopper unit is only one m times of the rated input current of the direct current motor, so that the step-down chopper can meet the requirements of the high-power direct current motor without adopting a power module or a parallel current sharing technology and using a common power switching tube, and the manufacturing cost of the step-down chopper is further reduced, and the requirements of a connecting wire and a connecting piece between the step-down chopper and the direct current motor on contact resistance and insulation are reduced, so that the manufacturing cost of the step-down chopper direct current motor driving device is greatly reduced.
In addition, because the upper bridge arm comprises a power switch tube, a capacitor, an inductor and a switch control end, the power switch tube is connected with the inductor in series, and the lower bridge arm comprises at least one diode, the buck chopper in the embodiment can realize that the power switch tube works in a zero-current soft switching state in the conducting process and the turning-off process by using the inductor and the capacitor with low cost for control, so that the switching loss of the power switch tube is greatly reduced, the heat productivity and the temperature rise of the buck chopper are greatly reduced, the fault rate of the buck chopper is reduced, the service life of the buck chopper is prolonged, and the reliability and the safety of the buck chopper direct-current motor driving device are improved.
In addition, because the control signal contains m switch control signals which are respectively corresponding to the m chopping units and are formed according to a preset phase staggering rule, and the switch control end in each chopping unit correspondingly receives the switch control signals, the phases of the output current ripples of each chopping unit are different, so that the ripple coefficient after the output current ripples of the m chopping units are superposed is reduced, the ripple coefficient of the output torque and the rotation speed of the direct current motor is further reduced, the electromagnetic interference, vibration and noise of the direct current motor are greatly reduced, and the performance and the service life of the buck chopping type direct current motor driving device are improved.
In addition, because m pairs of electric brushes are mutually independent, and the armature branch formed by each pair of electric brushes is independently supplied with power by the corresponding chopper unit, when a connecting line between one electric brush, the armature branch and the corresponding chopper unit has a fault, the direct current motor in the embodiment only needs to shield the part where the fault is located, and other normal parts can still work, so that the phenomenon of sudden runaway of the traditional direct current motor under the fault condition can be avoided, and the reliability and the safety of the voltage-reducing chopper type direct current motor driving device are improved.
The above embodiments are preferred examples of the present invention, and are not intended to limit the scope of the present invention.
For example, in the above-described embodiment, the lower arm includes one flywheel diode, but in the present invention, the lower arm may include a plurality of flywheel diodes connected in parallel with each other, and in this case, when any one of the flywheel diodes fails, the remaining flywheel diodes may also operate normally, contributing to improvement in reliability and safety of the step-down chopper type dc motor driving device.
As another example, in the above embodiment, the number of inductors in the upper arm is one. However, in the present invention, the number of the inductors in the upper arm may be plural, and in this case, when any one of the components fails, the remaining components may also operate normally, which is helpful to improve the reliability and safety of the step-down chopper dc motor driving apparatus.
For example, in the embodiment, if the step-down chopper type dc motor driving apparatus needs to operate normally, the amplifier needs to be in the operation mode, and therefore, the enable signal may not be applied to the amplifier.
For another example, in the case where the accuracy required for the armature current, the rotation speed, and the torque of the dc motor during steady operation is high, m may also be set according to the peak-to-peak value and the ripple coefficient of the corresponding armature current, rotation speed, and torque ripple.
Claims (10)
1. A step-down chopper type DC motor driving apparatus, comprising:
a DC motor having a rated voltage;
a DC power supply unit having a constant voltage corresponding to the rated voltage; and
a step-down chopper which converts the constant voltage into a variable voltage according to a control signal and supplies the variable voltage to the DC motor,
wherein the buck chopper has m chopper units,
each of the chopper units includes upper and lower arms, and first and second power supply output terminals,
the upper bridge arm and the lower bridge arm are connected in series,
the upper bridge arm is connected with the positive pole of the direct current power supply part, the lower bridge arm is connected with the negative pole of the direct current power supply part,
the upper bridge arm comprises at least one power switching tube, at least one capacitor, at least one inductor and a switch control end,
the power switch tube is connected with the inductor in series and is connected with the capacitor in parallel,
each of the power switch tubes has a control electrode,
the switch control terminal is formed based on the control pole,
the control signal includes m switching control signals respectively corresponding to the m chopper units and formed in accordance with a predetermined phase shift rule,
the switch control terminal is used for correspondingly receiving the switch control signal,
the lower leg comprises at least one diode,
the first power supply output end is arranged between the upper bridge arm and the lower bridge arm, the second power supply output end is arranged at the end part of the lower bridge arm connected with the direct-current power supply part,
m pairs of power supply output terminals are formed by the m first power supply output terminals of all the chopping units and the m second power supply output terminals of all the chopping units respectively corresponding to each other,
the direct current motor includes:
a housing;
m pairs of electric brushes fixed in the machine shell;
a stator arranged in the casing and including m pairs of main magnetic poles corresponding to the m pairs of brushes; and
a rotor disposed in the stator and including a plurality of armature windings coupled to each other in a predetermined coupling manner,
each pair of the main magnetic poles comprises an adjacent S-polarity main magnetic pole and an adjacent N-polarity main magnetic pole,
two of the brushes of each pair are located adjacent,
each pair of the brushes comprises an S-pole corresponding brush corresponding to the S-pole main magnetic pole and an N-pole corresponding brush corresponding to the N-pole main magnetic pole,
leading-out ends of the brushes corresponding to all S poles form m first wiring ends, and leading-out ends of the brushes corresponding to all N poles form m second wiring ends; or all the N poles correspond to the leading-out ends of the brushes to form m first terminals, all the S poles correspond to the leading-out ends of the brushes to form m second terminals,
the m first terminals and the m second terminals respectively form m pairs of external terminals,
the m pairs of external connecting terminals are connected with the m pairs of power output terminals in a one-to-one correspondence manner,
and m is a positive integer not less than 2.
2. The step-down chopper type dc motor driving apparatus according to claim 1, wherein:
wherein, the switching frequency fs of the power switch tube in each chopper unit, the inductance value Lr of the inductor, and the capacitance value Cr of the capacitor satisfy the following relations:
3. the step-down chopper type dc motor driving apparatus according to claim 1, wherein:
wherein, the predetermined phase staggering rule is that the phases of the m switch control signals are respectively staggered by m times of the switch period in sequence; or,
the m is an even number, and the m is an even number,
the predetermined phase shift rule is that the phases of the m switch control signals are sequentially shifted by m-th of a switching period, respectively.
4. The step-down chopper type dc motor driving apparatus according to claim 1, further comprising:
a control part including a controller and an amplifier,
wherein the controller generates the m switching control signals according to the predetermined phase staggering rule,
the amplifier amplifies the m switch control signals and correspondingly provides the m switch control signals to the m switch control terminals.
5. The step-down chopper type dc motor driving apparatus according to claim 4, wherein:
wherein the amplifier is composed of m independent amplifying units corresponding to the m chopper units,
each amplifying unit is provided with an amplifying signal output end which is correspondingly connected with the switch control end.
6. The step-down chopper type dc motor driving apparatus according to claim 1, wherein:
wherein, the upper bridge arm comprises one power switch tube, and when all the power switch tubes have the same maximum output current I1The maximum current of the direct current motor is ImaxWhen m satisfies the following condition: m is more than 1.1 (I)max÷I1) (ii) a Or,
the upper bridge arm comprises p power switch tubes which are connected in parallel, and when all the power switch tubes have the same maximum output current I1The maximum current of the direct current motor is ImaxAnd m satisfies the following condition: m is more than 1.1 (I)max÷(k×p×I1) P is a positive integer not less than 2, k is a parallel coefficient, 1/p<k<1。
7. The step-down chopper type dc motor driving apparatus according to claim 1, wherein:
wherein the predetermined coupling manner is any one of a single stack, a multiple stack, and a complex wave.
8. The step-down chopper type dc motor driving apparatus according to claim 1, wherein:
the power switch tube is a semi-control device or a full-control device, the semi-control device is a common thyristor, and the full-control device is any one of an electric field effect transistor, a gate turn-off thyristor, an integrated gate commutation thyristor, an insulated gate bipolar transistor and an electric power bipolar transistor.
9. An electrically powered device, comprising:
a voltage-reducing chopper type direct current motor driving device,
the step-down chopper type dc motor driving apparatus according to any one of claims 1 to 8.
10. The motorized equipment of claim 9, wherein:
wherein, the electrical equipment is any one of electric automobile, electric bicycle, artillery, tank and radar.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911119445.0A CN112825463A (en) | 2019-11-19 | 2019-11-19 | Voltage-reduction chopper type direct current motor driving device and electric equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911119445.0A CN112825463A (en) | 2019-11-19 | 2019-11-19 | Voltage-reduction chopper type direct current motor driving device and electric equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112825463A true CN112825463A (en) | 2021-05-21 |
Family
ID=75906164
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911119445.0A Withdrawn CN112825463A (en) | 2019-11-19 | 2019-11-19 | Voltage-reduction chopper type direct current motor driving device and electric equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112825463A (en) |
-
2019
- 2019-11-19 CN CN201911119445.0A patent/CN112825463A/en not_active Withdrawn
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Pollock et al. | Low cost, high power density, flux switching machines and drives for power tools | |
| CN109219923B (en) | Power output device | |
| CN110518770B (en) | Series excitation direct current motor | |
| CN101807874B (en) | Direct current series motor control method and device for realizing electronic moment commutation | |
| CN110518772B (en) | Parallel-series excitation direct current motor | |
| CN110518773B (en) | Separately excited direct current motor | |
| Prabhu et al. | Investigations on switched reluctance motors for automotive systems | |
| US11329582B2 (en) | Series shunt wound DC motor driving device and equipment | |
| US11387717B2 (en) | Series wound direct-current motor driving device and equipment | |
| CN112825463A (en) | Voltage-reduction chopper type direct current motor driving device and electric equipment | |
| CN112825449B (en) | Parallel-series excitation direct current motor | |
| CN112821819A (en) | Voltage-reduction chopper type direct current motor driving device and electric equipment | |
| CN112825448B (en) | Series-parallel excitation direct current motor | |
| CN112838796A (en) | Boost-buck chopper type direct current motor driving device and electric equipment | |
| CN110518769B (en) | Shunt-excited direct-current motor | |
| US11239775B1 (en) | Separately excited direct current motor drive apparatus and equipment | |
| US11329581B2 (en) | Shunt series wound direct current (DC) motor driving device and equipment | |
| CN111277098A (en) | Parallel-series excitation direct current motor | |
| CN112821820A (en) | Permanent magnet type direct current motor driving device and electric equipment | |
| CN112825447B (en) | Parallel-series excitation direct current motor | |
| CN113078858A (en) | Motor drive device and electric device | |
| US11394278B2 (en) | Shunt wound DC motor driving device and electrical equipment | |
| CN113141134A (en) | Series excited direct current motor driving device and electric equipment | |
| CN111313775A (en) | Permanent magnet type DC motor driving device | |
| KR102111851B1 (en) | Stator Winding Circuit and Saliency Electric Motor Including the Stator Winding Circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WW01 | Invention patent application withdrawn after publication | ||
| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20210521 |