CN113659896B - Motor control method, device, storage medium and motor control system - Google Patents
Motor control method, device, storage medium and motor control system Download PDFInfo
- Publication number
- CN113659896B CN113659896B CN202110897628.6A CN202110897628A CN113659896B CN 113659896 B CN113659896 B CN 113659896B CN 202110897628 A CN202110897628 A CN 202110897628A CN 113659896 B CN113659896 B CN 113659896B
- Authority
- CN
- China
- Prior art keywords
- carrier
- rotating speed
- current harmonic
- motor
- ratios
- 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.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 33
- 238000004590 computer program Methods 0.000 claims description 6
- 238000010586 diagram Methods 0.000 description 11
- 230000001360 synchronised effect Effects 0.000 description 9
- 238000006243 chemical reaction Methods 0.000 description 5
- 238000000605 extraction Methods 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 3
- 238000004378 air conditioning Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
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
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/0085—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation specially adapted for high speeds, e.g. above nominal speed
-
- 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
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/05—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation specially adapted for damping motor oscillations, e.g. for reducing hunting
-
- 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
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/22—Current control, e.g. using a current control loop
-
- 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
- H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
- H02P6/10—Arrangements for controlling torque ripple, e.g. providing reduced torque ripple
-
- 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
- H02P2207/00—Indexing scheme relating to controlling arrangements characterised by the type of motor
- H02P2207/05—Synchronous machines, e.g. with permanent magnets or DC excitation
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Ac Motors In General (AREA)
Abstract
The invention provides a motor control method, a motor control device, a storage medium and a motor control system, wherein the motor control method comprises the following steps: dividing the rotating speed range of the motor into more than two rotating speed intervals, wherein the rotating speed of each rotating speed interval is sequentially increased; when the rotating speed of the motor is in a rotating speed interval with the lowest rotating speed, outputting a set carrier frequency to control the motor; when the rotating speed of the motor is not in a rotating speed interval with the lowest rotating speed, acquiring the carrier ratio meeting a preset condition in more than two carrier ratios corresponding to the rotating speed interval with the lowest rotating speed, and controlling the motor according to the carrier ratio meeting the preset condition; wherein each of the rotational speed sections other than the rotational speed section in which the rotational speed is the lowest corresponds to two or more carrier ratios. The scheme provided by the invention can reduce the influence of low-order harmonic waves on the motor.
Description
Technical Field
The present invention relates to the field of control, and in particular, to a motor control method, apparatus, storage medium, and motor control system.
Background
In the traditional permanent magnet synchronous motor industry, the adverse phenomena of serious current harmonic, motor shake, serious motor noise, serious heating and the like occur due to lower carrier ratio value when the motor runs at high speed, and the running effect of the air conditioner at high speed is affected.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a motor control method, a motor control device, a storage medium and a motor control system, so as to solve the problem of serious current harmonic waves when a motor runs at a high speed in the prior art.
In one aspect, the present invention provides a motor control method, including: dividing the rotating speed range of the motor into more than two rotating speed intervals, wherein the rotating speed of each rotating speed interval is sequentially increased; when the rotating speed of the motor is in a rotating speed interval with the lowest rotating speed, outputting a set carrier frequency to control the motor; when the rotating speed of the motor is not in a rotating speed interval with the lowest rotating speed, acquiring the carrier ratio meeting a preset condition in more than two carrier ratios corresponding to the rotating speed interval with the lowest rotating speed, and controlling the motor according to the carrier ratio meeting the preset condition; wherein each of the rotational speed sections other than the rotational speed section in which the rotational speed is the lowest corresponds to two or more carrier ratios.
Optionally, each rotation speed interval corresponds to more than two carrier ratios, including: and more than two carrier ratios are arranged at equal intervals in a preset carrier ratio range, wherein each rotating speed interval corresponds to a different preset carrier ratio range.
Optionally, the carrier ratio satisfying the preset condition includes: a carrier ratio capable of minimizing a current harmonic determination value of the motor; the obtaining carrier ratios meeting preset conditions in more than two carrier ratios corresponding to the rotating speed interval where the rotating speed is located comprises the following steps: calculating a5 th order current harmonic value and a 7 th order current harmonic value at each of the two or more carrier ratios, respectively; according to the calculated 5-order current harmonic value and 7-order current harmonic value under each carrier ratio, determining a current harmonic judgment value corresponding to each carrier ratio in the more than two carrier ratios; and determining the carrier ratio capable of minimizing the current harmonic judgment value of the motor according to the current harmonic judgment value corresponding to each carrier ratio in the above two carrier ratios.
Optionally, determining the current harmonic determination value corresponding to each carrier ratio of the two or more carrier ratios according to the calculated 5 th order current harmonic value and 7 th order current harmonic value under each carrier ratio includes: the weighted average of the mode lengths of the 5 th order current harmonic component and the 7 th order current harmonic component at each carrier ratio is taken as a current harmonic determination value at the corresponding carrier ratio.
The invention further provides a motor control device, which divides the rotating speed range of the motor into more than two rotating speed intervals, and the rotating speed of each rotating speed interval is increased in turn; the device comprises: the control unit is used for outputting a set carrier frequency to control the motor when the rotating speed of the motor is in a rotating speed interval with the lowest rotating speed; an obtaining unit, configured to obtain a carrier ratio satisfying a preset condition from more than two carrier ratios corresponding to a rotation speed interval in which the rotation speed is located when the rotation speed of the motor is not in the rotation speed interval in which the rotation speed is the lowest; the control unit is further configured to: controlling the motor according to the carrier ratio meeting preset conditions; wherein each of the rotational speed sections other than the rotational speed section in which the rotational speed is the lowest corresponds to two or more carrier ratios.
Optionally, each rotation speed interval corresponds to more than two carrier ratios, including: and more than two carrier ratios are arranged at equal intervals in a preset carrier ratio range, wherein each rotating speed interval corresponds to a different preset carrier ratio range.
Optionally, the carrier ratio satisfying the preset condition includes: a carrier ratio capable of minimizing a current harmonic determination value of the motor; the obtaining unit obtains a carrier ratio meeting a preset condition in more than two carrier ratios corresponding to a rotating speed interval where the rotating speed is located, including: calculating a 5 th order current harmonic value and a 7 th order current harmonic value at each of the two or more carrier ratios, respectively; according to the calculated 5-order current harmonic value and 7-order current harmonic value under each carrier ratio, determining a current harmonic judgment value corresponding to each carrier ratio in the more than two carrier ratios; and determining the carrier ratio capable of minimizing the current harmonic judgment value of the motor according to the current harmonic judgment value corresponding to each carrier ratio in the above two carrier ratios.
Optionally, the obtaining unit determines, according to the calculated 5 th order current harmonic value and 7 th order current harmonic value at each carrier ratio, a current harmonic determination value corresponding to each carrier ratio of the two or more carrier ratios, including: the weighted average of the mode lengths of the 5 th order current harmonic component and the 7 th order current harmonic component at each carrier ratio is taken as a current harmonic determination value at the corresponding carrier ratio.
In a further aspect the invention provides a storage medium having stored thereon a computer program which when executed by a processor performs the steps of any of the methods described above.
In a further aspect the invention provides a motor control system comprising a processor, a memory and a computer program stored on the memory and executable on the processor, the processor implementing the steps of any of the methods described hereinbefore when the program is executed.
In yet another aspect, the present invention provides a motor control system, including a motor control device as described in any one of the preceding.
According to the technical scheme of the invention, more than two rotating speed intervals are arranged in a segmented mode according to the rotating speed range of the motor, the carrier frequency in the rotating speed interval with the lowest rotating speed is constant, the carrier ratio is changed, and more than two optional carrier ratios are respectively arranged in other rotating speed intervals, so that low-order harmonic components with great influence on the motor can be reduced. When the motor rotation speed is in a rotation speed interval other than the rotation speed interval with the lowest rotation speed, comparing the magnitudes of 5 times and 7 times of current harmonics under different carrier ratios, selecting the carrier ratio with the smallest current harmonic judgment value, reducing the influence of low order harmonics on the motor, reducing motor jitter and noise, reducing motor heating, and being beneficial to improving the energy efficiency of an air conditioning system.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and do not constitute a limitation on the invention. In the drawings:
FIG. 1 is a method schematic diagram of an embodiment of a motor control method provided by the present invention;
FIG. 2 shows the relationship between the 5 th and 7 th current harmonics in a rotating coordinate system;
FIG. 3 shows a simplified diagram of a 5 th order current harmonic, 7 th order current harmonic extraction module;
fig. 4 is a block diagram of carrier frequency control in accordance with an embodiment of the present invention;
FIG. 5 is a method schematic diagram of a motor control method according to an embodiment of the present invention;
Fig. 6 is a schematic structural diagram of an embodiment of a motor control device provided by the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to specific embodiments of the present invention and corresponding drawings. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that the terms "first," "second," and the like in the description and the claims of the present invention and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
In the traditional permanent magnet synchronous motor industry for air conditioners, most carrier frequencies are kept constant, but current harmonics are serious when the motor runs at a high speed; when the motor is at high speed, a small part of the synchronous modulation mode is switched into a carrier ratio fixed synchronous modulation mode, but the carrier ratio is generally set according to experience, and whether the influence of current harmonic waves on the motor can be reduced is not determined.
The invention provides a motor control method. The method is applicable to a device having an electric motor. Such as an air conditioner. The motor is for example a permanent magnet synchronous motor. Dividing the rotating speed range of the motor into more than two rotating speed sections, wherein the rotating speed of each rotating speed section is sequentially increased. For example, three rotation speed sections of low speed, medium speed and high speed are set in segments according to the rotation speed range of the motor, wherein the rotation speed is in [0, s1 ] as the low speed section, [ s1, s 2) as the medium speed section, [ s2, ≡) as the high speed section, and 0 < s1 < s2. That is, the rotational speed value in the preceding rotational speed section is larger than the rotational speed value in the following rotational speed section.
Fig. 1 is a schematic diagram of a motor control method according to an embodiment of the present invention.
As shown in fig. 1, the motor carrier frequency method at least includes step S110 and step S120 according to an embodiment of the present invention.
And step S110, outputting a set carrier frequency to control the motor when the rotating speed of the motor is in a rotating speed interval with the lowest rotating speed.
And the rotating speed interval with the lowest rotating speed in the above two rotating speed intervals adopts a set carrier frequency. For example, three rotation speed sections of low speed, medium speed and high speed are set in segments according to the rotation speed range of the motor, the rotation speed is [0, s1 ] is the low speed section, the carrier frequency in the low speed section is constant as s (the carrier frequency is unchanged, and the carrier ratio dynamically changes when the rotation speed changes). For example, when the permanent magnet synchronous motor enters a set low-speed section, the carrier frequency is constant at s, and the carrier ratio is dynamically changed.
And step S120, when the rotating speed of the motor is not in the rotating speed interval with the lowest rotating speed, acquiring the carrier ratio meeting the preset condition from more than two carrier ratios corresponding to the rotating speed interval with the lowest rotating speed, so as to control the motor according to the carrier ratio meeting the preset condition.
Wherein each of the rotation speed sections other than the rotation speed section at which the rotation speed is lowest corresponds to two or more carrier ratios, that is, each of the rotation speed sections after the rotation speed section at which the rotation speed is lowest (rotation speed greater than the rotation speed section at which the rotation speed is lowest) corresponds to two or more carrier ratios, the two or more carrier ratios including: and more than two carrier ratios are arranged at equal intervals in a preset carrier ratio range, and each rotating speed interval corresponds to a different preset carrier ratio range. The number of carrier ratios corresponding to each of the two or more rotation speed intervals sequentially increases. And the end value of the preset carrier ratio range corresponding to each rotating speed interval in the above two rotating speed intervals is sequentially increased, and the carrier ratio corresponding to the rotating speed interval with higher rotating speed is larger.
For example, three rotation speed intervals of low speed, medium speed and high speed are set in sections according to the rotation speed range of the motor, the carrier frequency in the low speed interval is constant as s, and N selectable carrier ratios are set at equal intervals in the carrier ratio [ a, b ] range in the medium speed interval, wherein a < b; m selectable carrier ratios are arranged at equal intervals in the range of carrier ratios [ b, c ] in the high-speed section, wherein b < c, a < b < c are increased with the increase of the motor rotation speed due to current harmonic, so the number of carrier ratios corresponding to the rotation speed section with lower rotation speed is set to be smaller than the number of carrier ratios corresponding to the rotation speed section with high rotation speed, and therefore N < M is set.
In a specific embodiment, the carrier ratio satisfying the preset condition includes: a carrier ratio capable of minimizing a current harmonic determination value of the motor; further, obtaining the carrier ratio satisfying the preset condition in the more than two carrier ratios corresponding to the rotating speed interval where the rotating speed is located includes: calculating a 5 th order current harmonic value and a 7 th order current harmonic value at each of the two or more carrier ratios, respectively; according to the calculated 5-order current harmonic value and 7-order current harmonic value under each carrier ratio, determining a current harmonic judgment value corresponding to each carrier ratio in the more than two carrier ratios; and determining the carrier ratio capable of minimizing the current harmonic judgment value of the motor according to the current harmonic judgment value corresponding to each carrier ratio in the above two carrier ratios.
For example, when the motor rotation speed is divided into three rotation speed sections of low speed, medium speed and high speed, the magnitudes of the current harmonics at different carrier ratios of 5 times and 7 times are compared in the medium speed section and the high speed section respectively as the current harmonic determination values, so as to determine the carrier ratio with the minimum current harmonic determination value.
Specifically, detecting phase current of the motor, and converting current i a,ib,ic under a three-phase static coordinate system into current i q,id under a two-phase rotating coordinate system through abc/dq conversion, wherein the current angle of a motor rotor is θ, and the following formula (1) can be obtained:
After the rotation coordinate current is obtained, 5-time and 7-time current harmonic components can be extracted through a 5-time and 7-time current harmonic module, and the final harmonic judgment value is obtained through processing.
Fig. 2 shows the relationship between the 5-order and 7-order current harmonics in the rotating coordinate system, and fig. 2 includes an a-b-c three-phase coordinate system, a d-q rotating coordinate system, a 5-order d-q rotating coordinate system, and a 7-order d-q rotating coordinate system, where ω represents the motor fundamental angular velocity, and θ is the current angle of the rotor. The 5 th harmonic current in the d-q coordinate system is a negative sequence component which is 6 times of the fundamental wave angular velocity, and the 7 th harmonic current in the d-q coordinate system is a positive sequence current component which is 6 times of the fundamental wave angular velocity. For a 5-time d-q rotating coordinate system, only 5 current harmonics are direct current, other current harmonics are alternating current, and 7 current harmonics are similar. The rotation coordinate down-conversion equations for converting the fundamental wave to the corresponding times under the 5 times d-q rotation coordinate system and the 7 times d-q rotation coordinate system are shown in the formulas (2) and (3) respectively:
Fig. 3 shows a simplified diagram of a 5 th order current harmonic, 7 th order current harmonic extraction module. As shown in fig. 3, the 5 th current harmonic and the 7 th current harmonic are converted into direct current values after being converted into corresponding rotation coordinate systems, I d5*,iq5*、id7*,iq7* can be filtered by a low-pass filter on the corresponding rotation coordinate systems to obtain 5 th current harmonic component I d5,iq5、id7,iq7 and 7 th current harmonic component I d5,iq5、id7,iq7 respectively, and then the module lengths I 5、I7 of the 5 th current harmonic component and the 7 th current harmonic component are respectively shown in the following formulas (4) and (5):
In a specific embodiment, determining the current harmonic determination value corresponding to each of the two or more carrier ratios according to the calculated 5 th order current harmonic value and 7 th order current harmonic value at each carrier ratio may include: taking the weighted average value of the modular lengths of the 5 th-order current harmonic component and the 7 th-order current harmonic component under each carrier ratio as a current harmonic judgment value under the corresponding carrier ratio; and selecting a current harmonic wave judgment value under the carrier ratio. Accordingly, the carrier ratio that can minimize the current harmonic determination value of the motor is determined from the current harmonic determination value corresponding to each of the two or more carrier ratios.
That is, the final current harmonic determination value I o is obtained by taking the weighted average of the 5 th current harmonic component and the 7 th current harmonic component mode length, as shown in the formula (6), wherein k 1+k2＝1,k1≥k2 > 0.
Io＝k1×I5+k2×I7(6)
After a carrier ratio capable of minimizing a current harmonic determination value of the motor is determined, the motor is controlled according to the carrier ratio. Specifically, the carrier ratio may be maintained in the current rotation speed interval, and when the current rotation speed interval is left, the carrier ratio satisfying the preset condition among the two or more carrier ratios corresponding to the rotation speed interval in which the rotation speed of the motor is located is obtained again, so as to control the motor according to the carrier ratio satisfying the preset condition.
Fig. 4 is a block diagram of carrier frequency control in accordance with an embodiment of the present invention. As shown in fig. 4, the carrier frequency control is mainly composed of carrier frequency control (module), phase current detection, abc/dq conversion module, and current harmonic extraction of 7 th order 5. Wherein the carrier frequency control section performs overall control of the carrier frequency by the motor rotation speed.
In order to clearly illustrate the technical scheme of the invention, the implementation flow of the motor control method provided by the invention is described in the following by a specific embodiment.
Fig. 5 is a schematic diagram of a motor control method according to an embodiment of the present invention. As shown in fig. 5, three rotation speed intervals of low speed, medium speed and high speed are set in sections according to the rotation speed range of the motor, firstly, the permanent magnet synchronous motor enters the set low speed interval, the carrier frequency is constant as s, and the carrier ratio is dynamically changed; then judging whether the rotating speed of the motor enters a medium speed section, if so, respectively calculating 5-order current harmonic wave judging values and 7-order current harmonic wave judging values of N carrier ratios corresponding to the medium speed section, selecting the carrier ratio with the smallest current harmonic wave judging value as the carrier ratio of the current medium speed section, and if the smallest current harmonic wave judging value corresponds to a plurality of carrier ratios (the current harmonic wave judging values calculated by two carrier ratios are the same and are the smallest), selecting a larger carrier ratio and keeping the carrier ratio unchanged in the speed section; and judging whether the motor enters a high-speed interval, if so, calculating 5 times and 7 times of current harmonic wave judging values of M carrier wave ratios in sequence, selecting the carrier wave ratio with the smallest current harmonic wave judging value as the carrier wave ratio of the high-speed interval, and if the smallest current harmonic wave judging value corresponds to a plurality of carrier wave ratios, selecting a larger carrier wave ratio and keeping the carrier wave ratio unchanged in the later rising speed.
The invention also provides a motor control device. The device is suitable for equipment with a motor. Such as an air conditioner. The motor is for example a permanent magnet synchronous motor.
Dividing the rotating speed range of the motor into more than two rotating speed sections, wherein the rotating speed of each rotating speed section is sequentially increased. For example, three rotation speed sections of low speed, medium speed and high speed are set in segments according to the rotation speed range of the motor, wherein the rotation speed is in [0, s1 ] as the low speed section, [ s1, s 2) as the medium speed section, [ s2, ≡) as the high speed section, and 0 < s1 < s2. That is, the rotational speed value in the preceding rotational speed section is larger than the rotational speed value in the following rotational speed section.
Fig. 6 is a schematic structural diagram of an embodiment of a motor control device provided by the present invention. As shown in fig. 6, the motor control device 100 includes a control unit 110 and an acquisition unit 120.
The control unit 110 is configured to output a set carrier frequency to control the motor when the rotational speed of the motor is in a rotational speed interval in which the rotational speed is the lowest.
And the rotating speed interval with the lowest rotating speed in the above two rotating speed intervals adopts a set carrier frequency. For example, three rotation speed sections of low speed, medium speed and high speed are set in segments according to the rotation speed range of the motor, the rotation speed is [0, s1 ] is the low speed section, the carrier frequency in the low speed section is constant as s (the carrier frequency is unchanged, and the carrier ratio dynamically changes when the rotation speed changes). For example, when the permanent magnet synchronous motor enters a set low-speed section, the carrier frequency is constant at s, and the carrier ratio is dynamically changed.
The obtaining unit 120 is configured to obtain a carrier ratio that satisfies a preset condition from more than two carrier ratios corresponding to a rotation speed interval in which the rotation speed is located when the rotation speed of the motor is not in the rotation speed interval in which the rotation speed is the lowest; the control unit 110 is further configured to: and controlling the motor according to the carrier ratio meeting the preset condition.
Wherein each of the rotation speed sections other than the rotation speed section at which the rotation speed is lowest corresponds to two or more carrier ratios, that is, each of the rotation speed sections after the rotation speed section at which the rotation speed is lowest (rotation speed greater than the rotation speed section at which the rotation speed is lowest) corresponds to two or more carrier ratios, the two or more carrier ratios including: and more than two carrier ratios are arranged at equal intervals in a preset carrier ratio range, and each rotating speed interval corresponds to a different preset carrier ratio range. The number of carrier ratios corresponding to each of the two or more rotation speed intervals sequentially increases. And the end value of the preset carrier ratio range corresponding to each rotating speed interval in the above two rotating speed intervals is sequentially increased, and the carrier ratio corresponding to the rotating speed interval with higher rotating speed is larger.
For example, three rotation speed intervals of low speed, medium speed and high speed are set in sections according to the rotation speed range of the motor, the carrier frequency in the low speed interval is constant as s, and N selectable carrier ratios are set at equal intervals in the carrier ratio [ a, b ] range in the medium speed interval, wherein a < b; m selectable carrier ratios are arranged at equal intervals in the range of carrier ratios [ b, c ] in the high-speed section, wherein b < c, a < b < c, and N < M is set here because the number of carrier ratios corresponding to the rotation speed section with lower rotation speed is smaller than the number of carrier ratios corresponding to the rotation speed section with higher rotation speed because the current harmonics increase with the increase of the rotation speed of the motor.
In a specific embodiment, the carrier ratio satisfying the preset condition includes: a carrier ratio capable of minimizing a current harmonic determination value of the motor; further, the obtaining unit 120 obtains a carrier ratio satisfying a preset condition from more than two carrier ratios corresponding to a rotation speed interval where the rotation speed is located, including: calculating a 5 th order current harmonic value and a 7 th order current harmonic value at each of the two or more carrier ratios, respectively; according to the calculated 5-order current harmonic value and 7-order current harmonic value under each carrier ratio, determining a current harmonic judgment value corresponding to each carrier ratio in the more than two carrier ratios; and determining the carrier ratio capable of minimizing the current harmonic judgment value of the motor according to the current harmonic judgment value corresponding to each carrier ratio in the above two carrier ratios.
For example, when the motor rotation speed is divided into three rotation speed sections of low speed, medium speed and high speed, the magnitudes of the current harmonics at different carrier ratios of 5 times and 7 times are compared in the medium speed section and the high speed section respectively as the current harmonic determination values, so as to determine the carrier ratio with the minimum current harmonic determination value.
Specifically, detecting phase current of the motor, and converting current i a,ib,ic under a three-phase static coordinate system into current i q,id under a two-phase rotating coordinate system through abc/dq conversion, wherein the current angle of a motor rotor is θ, and the following formula (1) can be obtained:
After the rotation coordinate current is obtained, 5-time and 7-time current harmonic components can be extracted through a 5-time and 7-time current harmonic module, and the final harmonic judgment value is obtained through processing.
Fig. 2 shows the relationship between the 5-order and 7-order current harmonics in the rotating coordinate system, and fig. 2 includes an a-b-c three-phase coordinate system, a d-q rotating coordinate system, a 5-order d-q rotating coordinate system, and a 7-order d-q rotating coordinate system, where ω represents the motor fundamental angular velocity, and θ is the current angle of the rotor. The 5 th harmonic current in the d-q coordinate system is a negative sequence component which is 6 times of the fundamental wave angular velocity, and the 7 th harmonic current in the d-q coordinate system is a positive sequence current component which is 6 times of the fundamental wave angular velocity. For a 5-time d-q rotating coordinate system, only 5 current harmonics are direct current, other current harmonics are alternating current, and 7 current harmonics are similar. The rotation coordinate down-conversion equations for converting the fundamental wave to the corresponding times under the 5 times d-q rotation coordinate system and the 7 times d-q rotation coordinate system are shown in the formulas (2) and (3) respectively:
Fig. 3 shows a simplified diagram of a 5 th order current harmonic, 7 th order current harmonic extraction module. As shown in fig. 3, the 5 th current harmonic and the 7 th current harmonic are converted into direct current values after being converted into corresponding rotation coordinate systems, I d5*,iq5*、id7*,iq7* can be filtered by a low-pass filter on the corresponding rotation coordinate systems to obtain 5 th current harmonic component I d5,iq5、id7,iq7 and 7 th current harmonic component I d5,iq5、id7,iq7 respectively, and then the module lengths I 5、I7 of the 5 th current harmonic component and the 7 th current harmonic component are respectively shown in the following formulas (4) and (5):
In a specific embodiment, determining the current harmonic determination value corresponding to each of the two or more carrier ratios according to the calculated 5 th order current harmonic value and 7 th order current harmonic value at each carrier ratio may include: taking the weighted average value of the modular lengths of the 5 th-order current harmonic component and the 7 th-order current harmonic component under each carrier ratio as a current harmonic judgment value under the corresponding carrier ratio; and selecting a current harmonic wave judgment value under the carrier ratio. Accordingly, the carrier ratio that can minimize the current harmonic determination value of the motor is determined from the current harmonic determination value corresponding to each of the two or more carrier ratios.
That is, the final current harmonic determination value I o is obtained by taking the weighted average of the 5 th current harmonic component and the 7 th current harmonic component mode length, as shown in the formula (6), wherein k 1+k2＝1,k1≥k2 > 0.
Io＝k1×I5+k2×I7(6)
After determining the carrier ratio that can minimize the current harmonic determination value of the motor, the control unit 110 controls the motor according to the carrier ratio. Specifically, the carrier ratio may be maintained in the current rotation speed interval, and when the current rotation speed interval is left, the carrier ratio satisfying the preset condition among the two or more carrier ratios corresponding to the rotation speed interval in which the rotation speed of the motor is located is obtained again, so as to control the motor according to the carrier ratio satisfying the preset condition.
The invention also provides a storage medium corresponding to the motor control method, on which a computer program is stored, which program, when being executed by a processor, implements the steps of any of the methods described above.
The invention also provides a motor control system corresponding to the motor control method, which comprises a processor, a memory and a computer program stored on the memory and capable of running on the processor, wherein the processor executes the program to realize the steps of any one of the methods.
The invention also provides a motor control system corresponding to the motor control device, which comprises any one of the motor control devices.
According to the scheme provided by the invention, more than two rotating speed intervals are arranged in a segmented mode according to the rotating speed range of the motor, the carrier frequency in the rotating speed interval with the lowest rotating speed is constant, the carrier ratio is changed, and more than two optional carrier ratios are respectively arranged in other rotating speed intervals, so that low-order harmonic components with larger influence on the motor can be reduced. When the motor rotation speed is in a rotation speed interval other than the rotation speed interval with the lowest rotation speed, comparing the magnitudes of 5 times and 7 times of current harmonics under different carrier ratios, selecting the carrier ratio with the smallest current harmonic judgment value, reducing the influence of low order harmonics on the motor, reducing motor jitter and noise, reducing motor heating, and being beneficial to improving the energy efficiency of an air conditioning system.
The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software that is executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope and spirit of the invention and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hardwired, or a combination of any of these. In addition, each functional unit may be integrated in one processing unit, each unit may exist alone physically, or two or more units may be integrated in one unit.
In the several embodiments provided in the present application, it should be understood that the disclosed technology may be implemented in other manners. The above-described embodiments of the apparatus are merely exemplary, and the division of the units, for example, may be a logic function division, and may be implemented in another manner, for example, a plurality of units or components may be combined or may be integrated into another system, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be through some interfaces, units or modules, or may be in electrical or other forms.
The units described as separate components may or may not be physically separate, and components as control devices may or may not be physical units, may be located in one place, or may be distributed over a plurality of units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.
The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied essentially or in part or all of the technical solution or in part in the form of a software product stored in a storage medium, including instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a usb disk, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), a removable hard disk, a magnetic disk, or an optical disk, or other various media capable of storing program codes.
The above description is only an example of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.
Claims (8)
1. A motor control method, characterized by comprising:
dividing the rotating speed range of the motor into more than two rotating speed intervals, wherein the rotating speed of each rotating speed interval is sequentially increased;
when the rotating speed of the motor is in a rotating speed interval with the lowest rotating speed, outputting a set carrier frequency to control the motor;
When the rotating speed of the motor is not in a rotating speed interval with the lowest rotating speed, acquiring the carrier ratio meeting a preset condition in more than two carrier ratios corresponding to the rotating speed interval with the lowest rotating speed, and controlling the motor according to the carrier ratio meeting the preset condition;
wherein, the carrier ratio satisfying the preset condition includes: a carrier ratio capable of minimizing a current harmonic determination value of the motor; each rotating speed interval except the rotating speed interval with the lowest rotating speed corresponds to more than two carrier ratios;
the obtaining carrier ratios meeting preset conditions in more than two carrier ratios corresponding to the rotating speed interval where the rotating speed is located comprises the following steps:
Calculating a 5 th order current harmonic value and a7 th order current harmonic value at each of the two or more carrier ratios, respectively;
According to the calculated 5-order current harmonic value and 7-order current harmonic value under each carrier ratio, determining a current harmonic judgment value corresponding to each carrier ratio in the more than two carrier ratios;
And determining the carrier ratio capable of minimizing the current harmonic judgment value of the motor according to the current harmonic judgment value corresponding to each carrier ratio in the above two carrier ratios.
2. The method of claim 1, wherein each of the speed intervals corresponds to two or more carrier ratios, comprising:
And more than two carrier ratios are arranged at equal intervals in a preset carrier ratio range, wherein each rotating speed interval corresponds to a different preset carrier ratio range.
3. The method of claim 1, wherein determining a current harmonic decision value for each of the two or more carrier ratios based on the calculated 5 th and 7 th order current harmonic values for each carrier ratio comprises:
The weighted average of the mode lengths of the 5 th order current harmonic component and the 7 th order current harmonic component at each carrier ratio is taken as a current harmonic determination value at the corresponding carrier ratio.
4. The motor control device is characterized in that the rotating speed range of the motor is divided into more than two rotating speed intervals, and the rotating speed of each rotating speed interval is sequentially increased; the device comprises:
The control unit is used for outputting a set carrier frequency to control the motor when the rotating speed of the motor is in a rotating speed interval with the lowest rotating speed;
an obtaining unit, configured to obtain a carrier ratio satisfying a preset condition from more than two carrier ratios corresponding to a rotation speed interval in which the rotation speed is located when the rotation speed of the motor is not in the rotation speed interval in which the rotation speed is the lowest;
The control unit is further configured to: controlling the motor according to the carrier ratio meeting preset conditions;
wherein, the carrier ratio satisfying the preset condition includes: a carrier ratio capable of minimizing a current harmonic determination value of the motor; each rotating speed interval except the rotating speed interval with the lowest rotating speed corresponds to more than two carrier ratios;
The obtaining unit obtains a carrier ratio meeting a preset condition in more than two carrier ratios corresponding to a rotating speed interval where the rotating speed is located, including:
Calculating a 5 th order current harmonic value and a7 th order current harmonic value at each of the two or more carrier ratios, respectively;
According to the calculated 5-order current harmonic value and 7-order current harmonic value under each carrier ratio, determining a current harmonic judgment value corresponding to each carrier ratio in the more than two carrier ratios;
And determining the carrier ratio capable of minimizing the current harmonic judgment value of the motor according to the current harmonic judgment value corresponding to each carrier ratio in the above two carrier ratios.
5. The apparatus of claim 4, wherein each of the speed intervals corresponds to two or more carrier ratios, comprising:
And more than two carrier ratios are arranged at equal intervals in a preset carrier ratio range, wherein each rotating speed interval corresponds to a different preset carrier ratio range.
6. The apparatus according to claim 4, wherein the obtaining unit determines the current harmonic determination value corresponding to each of the two or more carrier ratios from the calculated 5 th order current harmonic value and 7 th order current harmonic value for each carrier ratio, comprising:
The weighted average of the mode lengths of the 5 th order current harmonic component and the 7 th order current harmonic component at each carrier ratio is taken as a current harmonic determination value at the corresponding carrier ratio.
7. A storage medium having stored thereon a computer program which when executed by a processor performs the steps of the method of any of claims 1-3.
8. A motor control system comprising a processor, a memory and a computer program stored on the memory and executable on the processor, the processor implementing the steps of the method of any one of claims 1 to 3 when the program is executed, or comprising the motor control device of any one of claims 4 to 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110897628.6A CN113659896B (en) | 2021-08-05 | 2021-08-05 | Motor control method, device, storage medium and motor control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110897628.6A CN113659896B (en) | 2021-08-05 | 2021-08-05 | Motor control method, device, storage medium and motor control system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113659896A CN113659896A (en) | 2021-11-16 |
| CN113659896B true CN113659896B (en) | 2024-07-02 |
Family
ID=78478530
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110897628.6A Active CN113659896B (en) | 2021-08-05 | 2021-08-05 | Motor control method, device, storage medium and motor control system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113659896B (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106130435A (en) * | 2016-08-16 | 2016-11-16 | 深圳市英威腾交通技术有限公司 | A kind of Harmonics elimination PWM generates method |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104201969A (en) * | 2014-09-29 | 2014-12-10 | 永济新时速电机电器有限责任公司 | Modulating methods for semi-conductor device in diesel locomotive converter |
| CN106330045A (en) * | 2016-10-25 | 2017-01-11 | 北京新能源汽车股份有限公司 | Permanent magnet synchronous motor control system and control method of permanent magnet synchronous motor |
| CN110138284B (en) * | 2019-05-24 | 2021-04-30 | 苏州汇川联合动力***有限公司 | Driving motor control method, driving motor controller and readable storage medium |
| CN112350637B (en) * | 2020-09-17 | 2022-07-12 | 珠海格力电器股份有限公司 | Motor noise control method, computer readable storage medium and motor |
| CN112271969B (en) * | 2020-11-06 | 2022-05-24 | 江苏吉泰科电气股份有限公司 | Synchronous modulation method for transition from asynchronous modulation to phase synchronization |
| CN112865664B (en) * | 2021-01-05 | 2022-08-30 | 奇瑞新能源汽车股份有限公司 | SVPWM control method and device for inverter of electric automobile and electric automobile |
-
2021
- 2021-08-05 CN CN202110897628.6A patent/CN113659896B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106130435A (en) * | 2016-08-16 | 2016-11-16 | 深圳市英威腾交通技术有限公司 | A kind of Harmonics elimination PWM generates method |
Non-Patent Citations (1)
| Title |
|---|
| 交-直-交电力机车PWM调制方法研究;李威 等;《铁道学报》;第22卷(第6期);第26-31页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113659896A (en) | 2021-11-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102931857B (en) | Predictive control method of voltage-type PWM (pulse-width modulation) rectifier fixed-frequency model | |
| CN108988725B (en) | Permanent magnet synchronous motor current harmonic suppression system and method adopting improved complex vector PI controller | |
| CN109980998B (en) | Control method and device of permanent magnet synchronous motor and motor system | |
| CN111293939B (en) | Method for suppressing harmonic current of motor | |
| CN112564573B (en) | Hall installation deviation compensation method of permanent magnet synchronous motor based on high-frequency injection method | |
| CN109150052B (en) | High-frequency noise suppression method of random sine injection permanent magnet motor rotor position observer considering digital control delay | |
| CN113992075B (en) | Compensation circuit and control method for phase delay of brushless direct current motor | |
| CN111293946B (en) | Method for suppressing harmonic current of motor | |
| CN105429547B (en) | Single-phase brushless direct-current motor vector control method based on virtual phase structure | |
| CN113659896B (en) | Motor control method, device, storage medium and motor control system | |
| JP6116538B2 (en) | Motor control device | |
| CN104953910A (en) | Permanent magnet synchronous motor as well as control method and device thereof | |
| CN103001569A (en) | Method for tracking no-load rotating speed of high-voltage variable frequency motor | |
| CN109687799B (en) | Magnetic bearing rotor layered vibration compensation method based on assumed rotation coordinate | |
| CN104518721B (en) | The compressor control system and its noise suppressing method of convertible frequency air-conditioner | |
| CN111106775A (en) | Angle filtering method and system for permanent magnet synchronous motor | |
| CN107425761B (en) | Low-frequency control method and device for permanent magnet synchronous motor, compressor and air conditioner | |
| CN110391775A (en) | A kind of method for controlling position-less sensor based on no electrolytic capacitor drive system | |
| CN111030543B (en) | Zero-speed closed-loop starting method of direct-current variable-frequency air conditioner compressor | |
| CN112653360B (en) | Control method for high-speed permanent magnet synchronous motor without position sensor | |
| CN112803855B (en) | High-precision motor rotor position detection device and method | |
| Kou et al. | An envelope-prediction-based sensorless rotor position observation scheme for LCI-fed EESM at zero and low speed | |
| CN209805708U (en) | Control device of permanent magnet synchronous motor and motor system | |
| CN111262494A (en) | Control method and device of permanent magnet synchronous motor, storage medium and processor | |
| CN109660167A (en) | A kind of control method and device of motor |
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 | ||
| GR01 | Patent grant |