CN113037169B - System and method for starting non-inductive FOC control low-frequency band load of permanent magnet synchronous motor - Google Patents
System and method for starting non-inductive FOC control low-frequency band load of permanent magnet synchronous motor Download PDFInfo
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- CN113037169B CN113037169B CN201911339039.5A CN201911339039A CN113037169B CN 113037169 B CN113037169 B CN 113037169B CN 201911339039 A CN201911339039 A CN 201911339039A CN 113037169 B CN113037169 B CN 113037169B
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- 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
- H02P21/24—Vector control not involving the use of rotor position or rotor speed sensors
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- 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
- H02P21/0003—Control strategies in general, e.g. linear type, e.g. P, PI, PID, using robust control
- H02P21/0021—Control strategies in general, e.g. linear type, e.g. P, PI, PID, using robust control using different modes of control depending on a parameter, e.g. the speed
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- 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
- H02P21/13—Observer control, e.g. using Luenberger observers or Kalman filters
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- 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
- H02P21/14—Estimation or adaptation of machine parameters, e.g. flux, current or voltage
- H02P21/18—Estimation of position or speed
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- 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
- H02P21/34—Arrangements for starting
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- 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
- H02P25/00—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
- H02P25/02—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the kind of motor
- H02P25/022—Synchronous motors
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- 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
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Ac Motors In General (AREA)
Abstract
The invention discloses a permanent magnet synchronous motor non-inductive FOC control low-frequency load starting system and a method thereof, belonging to the technical field of permanent magnet synchronous motors.
Description
Technical Field
The invention relates to the technical field of permanent magnet synchronous motors, in particular to a system and a method for starting a non-inductive FOC control low-frequency band load of a permanent magnet synchronous motor.
Background
Under the promotion of the development of the electric trend of automobiles, more and more automobile parts realize electric driving. The motor is used for typical electric application on a pure electric commercial bus, and an air compressor on the bus is smaller in size, and a permanent magnet synchronous motor with higher efficiency is used for providing driving power to require stable starting work with load. Under the aims of lowest cost, high stability and higher efficiency, the permanent magnet synchronous motor is basically controlled by using a non-inductive FOC magnetic field space vector orientation algorithm.
However, as the noninductive FOC control algorithm depends on motor rotation speed observation, when the motor low frequency is close to 0 speed, the motor current is close to direct current, the motor rotation speed cannot be observed, and the magnetic field observation cannot be oriented, so that the motor is started in use and needs special treatment, and a high-frequency voltage injection method is used, but the method has high-frequency noise and is unacceptable to customers; there is a drag start using open loop VF, but the effect is less than ideal in the case of a load start.
Based on the above, the invention designs a system and a method for starting the low-frequency band load of the permanent magnet synchronous motor under the control of the non-inductive FOC, so as to solve the problems.
Disclosure of Invention
The invention aims to provide a system and a method for starting a low-frequency band load of a permanent magnet synchronous motor under the control of a non-inductive FOC, so as to solve the problems in the background technology.
In order to achieve the above purpose, the present invention provides the following technical solutions: the system comprises a permanent magnet synchronous motor for driving an electric automobile, a motor speed estimator for observing the rotating speed of the permanent magnet synchronous motor during low-frequency operation, and a non-inductive FOC control unit;
the non-inductive FOC control unit comprises a FOC motor magnetic field observation module for observing the rotating speed of the permanent magnet synchronous motor during high-frequency operation, a FOC magnetic field orientation algorithm control module for calculating the magnetic field orientation of the permanent magnet synchronous motor based on the rotating speed value of the permanent magnet synchronous motor, and a FOC control module for controlling the permanent magnet synchronous motor.
Preferably, the motor speed estimator comprises a fuzzy DTC flux linkage observer for observing the flux linkage of the permanent magnet synchronous motor stator.
Preferably, the motor speed estimator comprises a fuzzy PI stator resistance estimator, wherein the fuzzy PI stator resistance estimator estimates the stator resistance in real time based on a stator alpha-beta coordinate system of the permanent magnet synchronous motor, and compensates stator resistance changes caused by environmental factors.
In order to achieve the above purpose, the invention also provides a method for starting the sensorless FOC control low-frequency band load of the permanent magnet synchronous motor, which comprises the following steps:
s1, when the low-frequency band load of the permanent magnet synchronous motor is started, the motor rotating speed estimator observes the stator flux linkage of the permanent magnet synchronous motor through a fuzzy DTC flux linkage observer to obtain estimated values of electromagnetic torque and the stator flux linkage of the permanent magnet synchronous motor, and the rotating speed value of the permanent magnet synchronous motor at low frequency is calculated;
s2, the motor rotation speed estimator transmits rotation speed value information obtained through observation to the FOC magnetic field orientation algorithm control module, the FOC magnetic field orientation algorithm control module obtains the magnetic field orientation of the permanent magnet synchronous motor through calculation, and then the FOC control module achieves full-load starting control of the permanent magnet synchronous motor under the condition of low frequency through the magnetic field orientation of the permanent magnet synchronous motor;
s3, when the permanent magnet synchronous motor is operated from low frequency to medium and high frequency, namely the motor rotation speed reaches a set switching threshold value f, the fuzzy DTC flux linkage observer stops operating, and meanwhile the FOC motor magnetic field observation module starts to operate, and the switching is performed from fuzzy DTC flux linkage observation to non-induction FOC motor magnetic field observation.
Preferably, in S3, before the fuzzy DTC flux linkage observer stops working, the weighted stationary transition processing is performed, the fuzzy DTC flux linkage observer is switched according to a set percentage in the process of switching from low frequency to high frequency, the weight of the fuzzy DTC flux linkage observer is relatively large in the initial stage of switching, and the weight of the noninductive FOC magnetic field observer is relatively large in the final stage of switching.
Compared with the prior art, the invention has the beneficial effects that:
1. and observing the stator flux linkage of the permanent magnet synchronous motor through a fuzzy DTC flux linkage observer in the motor speed estimator to obtain the magnetic field orientation of the permanent magnet synchronous motor at low frequency, and acquiring motor speed information through the motor speed estimator by a non-inductive FOC control unit to realize smooth full-load starting control under the condition of low frequency.
2. After the motor is started under low frequency band load, when the motor rotation speed reaches a switching threshold f, the fuzzy DTC flux linkage observation is switched to the non-inductive FOC motor magnetic field observation, so that stable and accurate control of the permanent magnet synchronous motor can be realized.
3. The method is characterized in that the method is switched according to a certain percentage in the low-frequency-to-high-frequency switching process, the weight of the fuzzy DTC flux linkage observation is relatively large in the initial switching stage, the weight of the noninductive FOC flux linkage observation is relatively large in the final switching stage, smooth, stable and transition is realized from the switching start to the switching end, and the method is used for controlling a motor smoothly when an observer is switched and does not generate torque jitter phenomenon.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed for the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a step diagram of the working method of the present invention;
FIG. 2 is a block diagram of a method for starting a load of a non-inductive FOC low-frequency control according to the present invention;
FIG. 3 is a weighted diagram of the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. 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.
Referring to fig. 1-3, the present invention provides a technical solution: the system comprises a permanent magnet synchronous motor for driving an electric automobile, a motor speed estimator for observing the speed of the permanent magnet synchronous motor during low-frequency operation, and a non-inductive FOC control unit;
the non-inductive FOC control unit comprises a FOC motor magnetic field observation module for observing the rotating speed of the permanent magnet synchronous motor during high-frequency operation, a FOC magnetic field orientation algorithm control module for calculating the magnetic field orientation of the permanent magnet synchronous motor based on the rotating speed value of the permanent magnet synchronous motor, and a FOC control module for controlling the permanent magnet synchronous motor.
Further, the motor speed estimator comprises a fuzzy DTC flux linkage observer for observing the flux linkage of the permanent magnet synchronous motor stator.
Further, the motor rotating speed estimator comprises a fuzzy PI stator resistance estimator, wherein the fuzzy PI stator resistance estimator estimates the stator resistance in real time based on a stator alpha-beta coordinate system of the permanent magnet synchronous motor, and compensates stator resistance change caused by environmental factors, so that the estimation precision of electromagnetic torque and stator flux linkage in a fuzzy DTC flux linkage observer is improved.
In order to achieve the above purpose, the invention also provides a method for starting the sensorless FOC control low-frequency band load of the permanent magnet synchronous motor, which comprises the following steps:
s1, when a low-frequency band of the permanent magnet synchronous motor is started, a motor rotating speed estimator observes a stator flux linkage of the permanent magnet synchronous motor through a fuzzy DTC flux linkage observer to obtain estimated values of electromagnetic torque and the stator flux linkage of the permanent magnet synchronous motor, and calculates a rotating speed value of the permanent magnet synchronous motor at low frequency;
s2, the motor rotation speed estimator transmits rotation speed value information obtained through observation to the FOC magnetic field orientation algorithm control module, the FOC magnetic field orientation algorithm control module obtains the magnetic field orientation of the permanent magnet synchronous motor through calculation, and then the FOC control module achieves full-load starting control of the permanent magnet synchronous motor under the condition of low frequency through the magnetic field orientation of the permanent magnet synchronous motor;
s3, when the permanent magnet synchronous motor is operated from low frequency to medium and high frequency, namely the motor rotation speed reaches a set switching threshold value f, the fuzzy DTC flux linkage observer stops operating, and meanwhile the FOC motor magnetic field observation module starts to operate, and the fuzzy DTC flux linkage observation is switched to the non-induction FOC motor magnetic field observation.
Further, in S3, before the fuzzy DTC flux linkage observer stops working, the weighting stable transition treatment is carried out, the fuzzy DTC flux linkage observer is switched according to a set percentage in the process of switching from low frequency to high frequency, the weighting of the fuzzy DTC flux linkage observer is relatively large in the initial stage of switching, the non-inductive FOC magnetic field observer is relatively large in the final stage of switching, and the smooth stable transition is realized from the beginning of switching to the end of switching.
In the description of the present specification, the descriptions of the terms "one embodiment," "example," "specific example," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The preferred embodiments of the invention disclosed above are intended only to assist in the explanation of the invention. The preferred embodiments are not exhaustive or to limit the invention to the precise form disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best understand and utilize the invention. The invention is limited only by the claims and the full scope and equivalents thereof.
Claims (3)
1. The utility model provides a permanent magnet synchronous motor noninductive FOC control low frequency band carries starting system, this system is including the permanent magnet synchronous motor who is used for driving electric automobile, its characterized in that: the system also comprises a motor rotating speed estimator and a noninductive FOC control unit, wherein the motor rotating speed estimator is used for observing the rotating speed of the permanent magnet synchronous motor during low-frequency operation;
the non-inductive FOC control unit comprises a FOC motor magnetic field observation module for observing the rotating speed of the permanent magnet synchronous motor during high-frequency operation, a FOC magnetic field orientation algorithm control module for calculating the magnetic field orientation of the permanent magnet synchronous motor based on the rotating speed value of the permanent magnet synchronous motor, and a FOC magnetic field orientation algorithm control module for controlling the permanent magnet synchronous motor;
the motor rotating speed estimator comprises a fuzzy DTC flux linkage observer used for observing the flux linkage of the permanent magnet synchronous motor stator; the motor rotating speed estimator comprises a fuzzy PI stator resistance estimator, wherein the fuzzy PI stator resistance estimator estimates the stator resistance in real time based on a stator alpha-beta coordinate system of the permanent magnet synchronous motor, and compensates stator resistance changes caused by environmental factors;
the motor rotation speed estimator is estimated in the following way: and at low frequency, a fuzzy DCT flux linkage observer in a motor speed estimator is adopted to observe the stator flux linkage of the permanent magnet synchronous motor, then a speed value at low frequency is calculated based on the obtained stator flux linkage and electromagnetic torque, and then the motor speed estimator transmits the value to a FOC magnetic field orientation algorithm control module for magnetic field orientation, so that the starting under low frequency band load is realized.
2. The method for starting the sensorless FOC control low-frequency band of the permanent magnet synchronous motor is characterized by comprising the following steps of:
s1, when the low-frequency band load of the permanent magnet synchronous motor is started, a motor rotating speed estimator observes the stator flux linkage of the permanent magnet synchronous motor through a fuzzy DTC flux linkage observer to obtain estimated values of electromagnetic torque and the stator flux linkage of the permanent magnet synchronous motor, and the rotating speed value of the permanent magnet synchronous motor at low frequency is calculated;
s2, the motor rotation speed estimator transmits rotation speed value information obtained through observation to a FOC magnetic field orientation algorithm control module, the FOC magnetic field orientation algorithm control module obtains the magnetic field orientation of the permanent magnet synchronous motor through calculation, and then the FOC magnetic field orientation algorithm control module achieves full-load starting control of the permanent magnet synchronous motor under the condition of low frequency through the magnetic field orientation of the permanent magnet synchronous motor;
s3, when the permanent magnet synchronous motor is operated from low frequency to medium and high frequency, namely the motor rotation speed reaches a set switching threshold value f, the fuzzy DTC flux linkage observer stops operating, and meanwhile the FOC motor magnetic field observation module starts to operate, and the switching is performed from fuzzy DTC flux linkage observation to non-induction FOC motor magnetic field observation.
3. The method for starting the sensorless FOC control low-frequency band of the permanent magnet synchronous motor according to claim 2, wherein: and S3, before the fuzzy DTC flux linkage observer stops working, carrying out weighted stable transition treatment, switching according to a set percentage in the low-frequency to high-frequency switching process, wherein the weight of the fuzzy DTC flux linkage observer is larger in the initial stage of switching, and the weight of the noninductive FOC magnetic field observer is larger in the final stage of switching.
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| CN201910764U (en) * | 2010-12-14 | 2011-07-27 | 长春工业大学 | Permanent magnet synchronous motor (PMSM) direct torque control system based on terminal sliding mode |
| CN103944482B (en) * | 2014-05-12 | 2016-08-24 | 阳光电源股份有限公司 | Stator magnetic linkage, electromagnetic torque observation procedure and respectively apply two kinds of methods device |
| CN106549620B (en) * | 2016-10-26 | 2019-07-23 | 中冶南方（武汉）自动化有限公司 | A kind of Speed Sensorless Induction Motor vector control system low frequency processing method |
| CN109302111B (en) * | 2018-10-17 | 2020-09-15 | 山东大学 | Hybrid position observer of permanent magnet synchronous motor and position-sensorless servo system |
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