Motor parameter automatic measurement method and system

Abstract

The invention provides a motor parameter automatic measurement method and system, and relates to the technical field of permanent magnet synchronous motor system electrical and sensor parameter measurement, and the method comprises the steps: receiving a target motor parameter measurement instruction which indicates a target motor parameter needing to be measured; according to the target motor parameter measurement instruction, a target measurement strategy corresponding to measurement of target motor parameters is determined, and the target measurement strategy describes at least one target measurement module needing to be transferred and controlled for measurement of the target motor parameters and a target measurement control mode; and controlling at least one target measurement module to measure a target motor parameter corresponding to the measured motor according to the target measurement control mode. Through different measurement strategies corresponding to different preset motor parameters and a motor parameter automatic measurement system, the measurement of main motor parameters under the motor parameter automatic measurement system is realized, and the measurement efficiency and the motor parameter measurement precision are improved while the measurement efficiency is improved.

Description

Technical Field

[0001] The present application relates to the technical field of electrical and sensor parameter measurement of permanent magnet synchronous motor systems, and in particular to a method and system for automatically measuring motor system parameters. Background Art

[0002] Permanent magnet synchronous motors have permanent magnets and do not require additional excitation current. They have the advantages of simple structure, small size, high efficiency, high power factor, and low moment of inertia. They have been widely used in the field of new energy electric drives. Control methods such as speed sensorless control, weak magnetic control, and loss compensation control are widely used in permanent magnet synchronous motor controllers. The motor parameters corresponding to permanent magnet synchronous motors have a great influence on the control performance of these control strategies.

[0003] Therefore, it is very necessary to accurately measure the parameters of the permanent magnet synchronous motor system. Its accuracy is not only related to the accuracy of permanent magnet synchronous motor simulation and control model establishment in the early stage of electronic control system development, but also to the accuracy of hardware-in-the-loop simulation test on test controller performance analysis in the verification stage of electronic control system development.

[0004] The existing public solutions for measuring the parameters of permanent magnet synchronous motors usually only target certain specific parameters, and lack a complete solution or system that can efficiently and automatically measure the main motor parameters. Therefore, under existing technical conditions, to achieve systematic measurement of the main motor parameters, it is necessary to build multiple independent test systems or configure different test environments. This not only reduces the measurement efficiency, but also affects the measurement accuracy due to the frequent switching of the test environment. Summary of the invention

[0005] In view of this, the purpose of the present application is to provide at least a method and system for automatic measurement of motor system parameters. By pre-setting different measurement strategies corresponding to different motor parameters and a motor parameter automatic measurement system, the measurement of main motor parameters under the motor parameter automatic measurement system can be realized, thereby improving the measurement efficiency and the motor parameter measurement accuracy.

[0006] This application mainly includes the following aspects: In a first aspect, an embodiment of the present application provides a method for automatically measuring motor parameters. In a possible implementation, a bench test control system is applied to an automatic motor parameter measurement system. The automatic motor parameter measurement system also includes multiple measurement modules, and the multiple measurement modules include a dynamometer module, a power collector, a motor controller, a power supply module, a motor ambient temperature control module and a cooling module. The motor under test is placed in an environmental chamber. The bench test control system is connected to the multiple measurement modules respectively. The motor under test is connected to the power collector, the dynamometer module and the motor controller respectively. The power collector is also connected to the motor controller. The motor controller is connected to the power supply module. The motor controller and the motor under test are also connected to the cooling module respectively. The motor under test is connected to the dynamometer module via a torque measurement shaft. The method includes: receiving a target motor parameter measurement instruction, the target motor parameter measurement instruction indicates a target motor parameter that needs to be measured; according to the target motor parameter measurement instruction, determining a target measurement strategy corresponding to the target motor parameter, the target measurement strategy describes at least one target measurement module and a target measurement control method required to mobilize and control the target motor parameter; and controlling at least one target measurement module according to the target measurement control method to measure the target motor parameter corresponding to the motor under test.

[0007] In one possible implementation, if the target motor parameter is the number of motor pole pairs, the number of motor pole pairs corresponding to the motor under test is determined in the following manner: controlling the motor controller to operate in shutdown mode; controlling the dynamometer module to operate in speed control mode and dragging the motor under test to a given speed; collecting the back electromotive force signal corresponding to the motor under test through a power collector and obtaining the voltage frequency of the power collector based on the back electromotive force signal feedback; and determining the ratio between the voltage frequency and the given speed as the number of motor pole pairs corresponding to the motor under test.

[0008] In a possible implementation, if the target motor parameter is the rotor permanent magnet flux and its temperature characteristics, the rotor permanent magnet flux and its temperature characteristics corresponding to the motor under test are determined in the following manner: the command temperature of the motor ambient temperature control module and the cooling module are set to the same given temperature; the motor controller is controlled to be in shutdown mode; the dynamometer module is controlled to be in speed control mode and the motor under test is dragged to a given speed; multiple rounds of rotor permanent magnet flux temperature characteristics tests are started in sequence, and the rotor permanent magnet flux temperature characteristics test includes: collecting the back electromotive force signal between any two phases of the motor under test through a power acquisition instrument, and determining the rotor permanent magnet flux of the motor under test at the current given temperature according to the back electromotive force signal; changing the command temperature of the motor ambient temperature control module and the cooling module and executing the next round of rotor permanent magnet flux temperature characteristics test; based on the rotor permanent magnet flux corresponding to the motor under test at different given temperatures, a rotor permanent magnet flux temperature characteristics curve corresponding to the motor under test is established, and the rotor permanent magnet flux temperature characteristics curve describes the temperature characteristics corresponding to the rotor permanent magnet flux corresponding to the motor under test. In a possible implementation manner, the rotor permanent magnet flux corresponding to the motor under test at each ambient temperature is determined by the following formula:

[0009] In this formula, represents the rotor permanent magnet flux, Indicates the voltage amplitude determined by the power harvester based on the back EMF signal. represents the given speed, and P represents the number of motor pole pairs.

[0010] In a possible implementation, if the target motor parameter is a resolver rotor position offset value, the resolver rotor position offset value corresponding to the measured motor is determined in the following manner: S1, respectively controlling the dynamometer module to operate in the shutdown mode and controlling the motor controller to be in the current control mode; S2, setting the rotor position corresponding to the measured motor to 0°, the direct-axis current to the rated current, and the quadrature-axis current to 0 through the motor controller; S3, applying a DC current to the three phases corresponding to the measured motor through the motor controller, wherein phase A is a positive current, and phases B and C are negative currents; S4, reading the resolver position sensor after the position of the measured motor is stable to obtain a displacement feedback value; repeating steps S1 to S4 multiple times, and taking the average value corresponding to the multiple displacement feedback values ​​as the resolver rotor position offset value corresponding to the measured motor.

[0011] In a possible implementation, if the target motor parameters are the comprehensive resistance, its temperature characteristics and the dead-zone error voltage, the comprehensive resistance, its temperature characteristics and the dead-zone error voltage corresponding to the motor under test are determined in the following manner: the command temperature of the motor ambient temperature control module and the cooling module are set to the same given temperature; the motor controller is controlled to work in the current control mode and the dynamometer module is controlled to work in the shutdown mode respectively; multiple rounds of comprehensive resistance temperature characteristic tests are started in sequence, and the comprehensive resistance temperature characteristic test includes: applying different direct-axis currents to the motor under test through the motor controller; determining the direct-axis voltage of the motor under test under different direct-axis currents through the power acquisition instrument; fitting the direct-axis voltages under different direct-axis currents to determine the comprehensive resistance and dead-zone error voltage of the motor under test at the current given temperature; changing the command temperature of the motor ambient temperature control module and the cooling module and executing the next round of comprehensive resistance temperature characteristic test; based on the comprehensive resistance corresponding to the motor under test at different given temperatures, a comprehensive resistance temperature characteristic curve corresponding to the motor under test is established, and the comprehensive resistance temperature characteristic curve describes the characteristics of the comprehensive resistance corresponding to the motor under test changing with temperature.

[0012] In a possible implementation, if the target motor parameters are a direct-axis inductance matrix and a quadrature-axis inductance matrix, the direct-axis inductance matrix and the quadrature-axis inductance matrix corresponding to the motor under test are determined in the following manner: the command temperature of the motor ambient temperature control module and the cooling module are set to the same given temperature; the motor controller is controlled to work in a current control mode; the dynamometer module is controlled to work in a speed control mode to drag the motor under test to a given speed; different shaft currents are applied to the motor under test in sequence through the motor controller, and the shaft current includes a direct-axis current and a quadrature-axis current; under each set of shaft currents, the following are performed: the direct-axis voltage and the quadrature-axis voltage corresponding to the motor under test are determined through a power acquisition instrument; the direct-axis inductance and the quadrature-axis inductance of the motor under test under the set of shaft currents are determined according to the direct-axis current, the quadrature-axis current, the direct-axis voltage, the quadrature-axis voltage, the motor speed, and the rotor permanent magnet flux and the comprehensive resistance of the motor under test at a given temperature, combined with the shaft voltage equation corresponding to the motor under test; a direct-axis inductance matrix and a quadrature-axis inductance matrix are formed according to the direct-axis inductance and the quadrature-axis inductance corresponding to the motor under test under each set of shaft currents.

[0013] In a possible implementation manner, the axis voltage equation includes a direct axis voltage equation and a quadrature axis voltage equation, wherein the direct axis voltage equation is:

[0014] in, represents the direct-axis voltage determined by the power acquisition instrument, Indicates the comprehensive resistance of the motor under test at a given temperature. represents the direct axis current, represents the direct-axis inductance, Indicates the voltage frequency corresponding to the motor under test determined by the power acquisition instrument. represents the quadrature-axis inductance, represents the quadrature axis current; the quadrature axis voltage equation is:

[0015] in, represents the quadrature axis voltage determined by the power acquisition instrument, It represents the rotor permanent magnet flux of the motor under test at a given temperature.

[0016] In a second aspect, an embodiment of the present application further provides a motor parameter automatic measurement system, which includes a bench test control system, a dynamometer module, a power acquisition instrument, a motor controller, a power supply module, a motor ambient temperature control module and a cooling module, wherein the bench test control system is applied to the motor parameter automatic measurement method provided in any of the above embodiments; the dynamometer module is used to operate in a speed control mode or a shutdown mode according to a control instruction issued by the bench test control system; the motor controller is used to operate in a shutdown mode or a current control mode according to a control instruction issued by the bench test controller system; the power supply module is used to operate in a shutdown mode or a current control mode according to a control instruction issued by the bench test control system. Control instructions, output controllable DC voltage or disconnect its own output from the motor controller; a motor environment temperature control module, which is used to control the temperature in the environmental chamber under the control instructions issued by the bench test control system; a cooling module, which is used to automatically adjust the cooling flow rate under the control instructions issued by the bench test control system to maintain the constant temperature of the motor under test and its corresponding motor controller; a power acquisition instrument, which is used to collect the PWM modulated voltage signal applied by the motor controller to the winding of the motor under test, or the back electromotive force voltage signal generated when the motor rotates passively, and collect the current signal in the winding of the motor under test through the current sensor, and transmit the processed voltage and current data to the bench test control system.

[0017] An automatic motor parameter measurement method and system provided in an embodiment of the present application relates to the technical field of electrical and sensor parameter measurement of permanent magnet synchronous motor systems, including: receiving a target motor parameter measurement instruction, the target motor parameter measurement instruction indicating the target motor parameter to be measured; determining a target measurement strategy corresponding to the target motor parameter according to the target motor parameter measurement instruction, the target measurement strategy describing at least one target measurement module and a target measurement control method required to mobilize and control the target motor parameter; controlling at least one target measurement module to measure the target motor parameter corresponding to the measured motor according to the target measurement control method. By pre-setting different measurement strategies corresponding to different motor parameters and a motor parameter automatic measurement system, the measurement of the main motor parameters under the motor parameter automatic measurement system is achieved, thereby improving the measurement efficiency and the motor parameter measurement accuracy.

[0018] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A schematic diagram of the structure of a motor parameter automatic measurement system provided in an embodiment of the present application is shown; Figure 2 A method for automatically measuring motor parameters provided by an embodiment of the present application is shown; Figure 3 A current test grid diagram for measuring the inductance matrix of a motor under test provided by an embodiment of the present application is shown; Figure 4 A direct-axis inductor matrix provided in an embodiment of the present application is shown; Figure 5 A cross-axis inductor matrix provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0021] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of explanation and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in this application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art, under the guidance of the content of the present application, can add one or more other operations to the flowchart, or remove one or more operations from the flowchart.

[0022] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0023] For the electronic control system development process based on the V process, the model-in-the-loop testing stage needs to rely on motor parameters to establish a mathematical model of the controlled object. An accurate mathematical model is particularly important for early solution verification. In the verification stage of electronic control system development, hardware-in-the-loop simulation testing is the main testing method for the controller after hardware and software integration. In this stage, motor parameters are also needed to simulate the real controlled object and test the performance of the controller.

[0024] The existing public solutions for measuring the parameters of permanent magnet synchronous motors usually only target certain specific parameters, and lack a complete solution or system that can efficiently and automatically measure the main motor parameters. Therefore, under existing technical conditions, to achieve systematic measurement of the main motor parameters, it is necessary to build multiple independent test systems or configure different test environments. This not only reduces the measurement efficiency, but also affects the measurement accuracy due to the frequent switching of the test environment.

[0025] Based on this, the embodiment of the present application provides a motor parameter automatic measurement method and a motor parameter automatic measurement system, which realizes the measurement of main motor parameters under the motor parameter automatic measurement system through different measurement strategies corresponding to different motor parameters set in advance, improves the measurement efficiency and improves the motor parameter measurement accuracy, as follows: See also Figure 1 , Figure 1 FIG. 1 is a schematic diagram showing a structure of a motor parameter automatic measurement system provided by an embodiment of the present application. Figure 1 As shown, the motor parameter automatic measurement system provided in the embodiment of the present application includes a bench test control system 1 and multiple measurement modules, and the multiple measurement modules include a dynamometer module 2, a power collector 3, a motor controller 4, a power supply module 5, a motor ambient temperature control module 6 and a cooling module 7.

[0026] The motor 8 under test is placed in an environmental chamber 9, the environmental chamber 9 and the dynamometer module 2 are placed on a bench test base 10, the bench test control system 1 is respectively connected to the dynamometer module 2, the power collector 3, the motor controller 4, the motor ambient temperature control module 6, the power supply module 5, the motor ambient temperature control module 6 and the cooling module 7, the motor 8 under test is respectively connected to the power collector 3, the dynamometer module 2 and the motor controller 4, the power collector 3 is also connected to the motor controller 4, the motor controller 4 is connected to the power supply module 5, the motor controller 4 and the motor 8 under test are also respectively connected to the cooling module 7, and the motor ambient temperature control module 6 is also connected to the environmental chamber 9.

[0027] In a specific embodiment, the motor 8 under test is a permanent magnet synchronous motor, the power supply module 5 is a battery simulator or a DC power supply, and the dynamometer module 2 further includes a dynamometer 21 and a dynamometer inverter 22 connected to each other, the dynamometer inverter 22 is connected to the bench test control system 1, and the dynamometer 21 is connected to the motor 8 under test through a torque measurement shaft.

[0028] See also Figure 2 , Figure 2 A method for automatically measuring motor parameters provided by an embodiment of the present application is shown. Figure 2 As shown, the motor parameter automatic measurement method provided by the present application is applied to Figure 1 The bench test control system 1 shown, specifically, comprises the following steps: S100, receiving a target motor parameter measurement instruction.

[0029] The target motor parameter measurement instruction indicates the target motor parameter to be measured.

[0030] S200: Determine a target measurement strategy corresponding to the target motor parameter according to the target motor parameter measurement instruction.

[0031] The target determination strategy describes at least one target determination module and a target determination control method required to determine the target motor parameters.

[0032] S300 , controlling at least one target determination module to determine target motor parameters corresponding to the motor under test according to a target determination control method.

[0033] Specifically, in steps S100 to S300 provided in the present application, for the bench test control system 1 provided in the present application, a target motor parameter measurement instruction for the motor under test 8 is obtained from the host computer, the target motor parameter measurement instruction is parsed, and the target motor parameters that need to be measured are obtained. In the present application, the motor parameters include the number of motor poles, the magnetic flux of the rotor permanent magnet and its temperature characteristics, the rotary rotor position offset value, the comprehensive resistance value and its temperature characteristics, the dead zone error voltage of the power switching device, the direct-axis inductance matrix and the quadrature-axis inductance matrix. A measurement strategy corresponding to each motor parameter is pre-created, and a mapping relationship between the motor parameter and its corresponding measurement strategy is created. The target motor parameter is at least one of the above-mentioned motor parameters. According to the mapping relationship between the motor parameter and its corresponding measurement strategy, a target measurement strategy corresponding to the target motor parameter is determined, and at least one target measurement module is controlled according to the target measurement control mode indicated by the target measurement strategy to complete the measurement of the target motor parameter corresponding to the motor under test.

[0034] In the present application, the user can send corresponding target motor parameter measurement instructions to the bench test control system through the upper computer according to the motor parameter measurement requirements. After receiving the corresponding target motor parameter measurement instructions, the bench test control system mobilizes the corresponding measurement module to complete the measurement of the target motor parameters. Since the bench test system integrates the measurement modules required to measure all motor parameters, the present application can use measurement strategies corresponding to different motor parameters to complete the measurement of the main motor parameters of the motor under test, thereby improving the comprehensiveness of the motor parameter measurement and improving the measurement efficiency. During the measurement process, there is no need to move or switch the position or environment of the motor under test. It is only necessary to determine the measurement module used to measure the motor parameters and start the corresponding measurement control method to complete the measurement process. Not only is the step simplified, but the stability of the entire measurement process is also greatly improved.

[0035] In a specific embodiment, before executing step S100, the present application includes: Input basic parameters corresponding to the motor under test 8 and the motor controller 4 into the bench test control system 1, the basic parameters include motor rated voltage, motor rated current, motor peak current, motor rated speed, motor peak speed, motor rated torque and motor peak torque, and the bench test control system 1 sets the voltage and current of the object under test according to the basic parameters, mainly limiting the bench test control system 1 to measure different motor parameters within the normal working range of the object under test.

[0036] It should be noted that the motor controller 4 should match the measured motor 8 in parameters such as voltage and current, otherwise the controller may be damaged. Preferably, taking the measured motor 8 with a rated voltage of 540V, a rated current of 320A, a peak current of 640A, a rated speed of 650rpm, a peak speed of 3000rpm, a rated torque of 1500Nm and a peak torque of 2800Nm as an example, the corresponding working parameters of the motor controller 4 should be: rated voltage of 576V, maximum voltage of 750A, rated current of 320A and peak current of 650A. In this way, the working parameters of the motor controller 4 are consistent with the basic parameters corresponding to the measured motor, and matching and subsequent measurement of the motor parameters can be performed.

[0037] In a preferred embodiment, if the target motor parameter is the number of motor pole pairs, the number of motor pole pairs corresponding to the measured motor 8 is determined by: The motor controller 4 is controlled to work in the shutdown mode, the dynamometer module 2 is controlled to work in the speed control mode and drag the motor 8 under test to a given speed, the back electromotive force signal corresponding to the motor 8 under test is collected through the power collector 3, and the voltage frequency of the power collector 3 based on the back electromotive force signal feedback is obtained, and the ratio between the voltage frequency and the given speed is determined as the number of motor poles corresponding to the motor 8 under test.

[0038] In a specific implementation, the bench test control system 1 sends a circuit breaker command to the power supply module 5 to disconnect the electrical connection between the power supply module 5 and the motor controller 4 corresponding to the motor 8 under test. The bench test control system 1 sends a shutdown mode command to the motor controller 4. The motor controller 4 controls the IGBT in the three-phase bridge in its corresponding drive circuit to turn off, so that the motor controller 4 is in shutdown mode. At this time, the motor controller 4 does not work and no longer applies a control voltage to the motor 8 under test. The voltage in the three-phase line of the motor 8 under test is completely generated by the back electromotive force. The bench test control system 1 sends a speed control mode command and a given speed to the dynamometer inverter 22 in the dynamometer module 2. After receiving the speed control mode command and the given speed, the dynamometer inverter 22 drives the dynamometer 21 to run, so as to further drag the motor 8 under test to the given speed through the dynamometer 21. , preferably, in this measurement case, the given speed The rated speed of the motor 8 under test can be the motor rated speed corresponding to the motor 8 under test. The power collector 3 collects the line voltage between any two phases of the three phases of the motor 8 under test, and uses it as the back electromotive force signal corresponding to the motor 8 under test. After being processed by the voltage divider circuit and the comparison circuit inside the power collector 3, the sinusoidal line voltage is converted into a square wave frequency signal to determine the frequency corresponding to the square wave frequency signal. The voltage frequency corresponding to the motor 8 under test is determined and transmitted to the bench test control system 1. The bench test control system 1 converts the voltage frequency With given speed The ratio between them is determined as the number of motor pole pairs P corresponding to the measured motor 8, that is:

[0039] Taking the speed of the motor 8 under test as 650rpm as an example, the line voltage between the two phases AB corresponding to the motor 8 under test is collected, and the voltage frequency is determined to be 65Hz by the power acquisition instrument 3, then:

[0040] In a preferred embodiment, if the target motor parameter is the rotor permanent magnet flux and its temperature characteristics, the rotor permanent magnet flux and its temperature characteristics corresponding to the motor under test 8 are measured in the following manner: A temperature control instruction is sent to the ambient temperature control module 6 to realize closed-loop control of the ambient chamber temperature through the ambient temperature control module 6. The motor ambient temperature control module 6 controls the ambient temperature in the ambient chamber 9 to a given temperature T under the temperature control instruction. A temperature control instruction is sent to the cooling module 7 to control the temperature of the motor 8 under test to a given temperature T. A circuit breaker instruction is sent to the power supply module 5 to disconnect the electrical connection between the power supply module 5 and the motor controller 4 corresponding to the motor 8 under test, and the motor controller 4 is controlled to be in the shutdown mode, so that the IGBT in the three-phase bridge corresponding to the motor controller 4 is turned off, and no control voltage is applied to the motor 8 under test. At this time, the voltage in the three-phase line of the motor 8 under test is completely generated by the back electromotive force. A speed control instruction and a given speed are sent to the dynamometer inverter 22 to control the dynamometer module 2 to be in the speed control mode and drag the motor 8 under test to a given speed through the dynamometer 21. , start multiple rounds of rotor permanent magnet flux temperature characteristic tests in sequence, each round of rotor permanent magnet flux temperature characteristic tests includes: The back electromotive force signal between any two phases of the motor 8 under test is collected by the power collector 3, and the corresponding line voltage peak value and voltage frequency are determined according to the back electromotive force signal. According to the line voltage peak value and voltage frequency, the rotor permanent magnet flux of the motor 8 under test at the current given temperature T is determined. .

[0041] Based on the rotor permanent magnet flux corresponding to the motor 8 under test at different given temperatures T , establish the rotor permanent magnet flux temperature characteristic curve corresponding to the measured motor 8, the rotor permanent magnet flux temperature characteristic curve describes the rotor permanent magnet flux corresponding to the measured motor 8 The corresponding temperature characteristics, that is, the corresponding rotor permanent magnet flux of the motor under test at different temperatures T .

[0042] In a preferred embodiment, the rotor permanent magnet flux corresponding to the motor 8 under test at each given temperature T is determined by the following formula: ,Right now:

[0043] in, represents the rotor permanent magnet flux, represents the voltage amplitude determined by the power collector 3 based on the back electromotive force signal, Indicates the given speed, and P indicates the number of motor pole pairs.

[0044] In a specific example, the ambient temperature corresponding to the environmental chamber 9 of the motor 8 under test is 65°C. The dynamometer 21 works in the speed control mode, and the given speed is 650rpm. The line voltage peak between the AB phases corresponding to the motor 8 under test is 213V. After voltage division and shaping, assuming that the number of motor pole pairs is 6, the rotor permanent magnet flux corresponding to the motor 8 under test at the given temperature of 65°C is for: 0.301Wb.

[0045] In a specific embodiment, the present application continuously changes the command temperature of the motor environment temperature control module 6 and the cooling module 7 so that the temperature T corresponding to the measured motor 8 is continuously changed, and the rotor permanent magnet flux of the measured motor 8 at each given temperature T is calculated based on the data collected by the power acquisition instrument 3. , further, by measuring the rotor permanent magnet flux of the motor 8 under test at different given temperatures T , construct the rotor permanent magnet flux corresponding to the motor under test 8 The mapping relationship between the temperature T and the rotor permanent magnet flux temperature characteristic curve is formed, thereby obtaining the rotor permanent magnet flux corresponding to the measured motor 8 Corresponding temperature characteristics.

[0046] In a preferred embodiment, if the target motor parameter is a resolver rotor position offset value, the resolver rotor position offset value corresponding to the measured motor 8 is determined by the following method: The dynamometer module 2 is controlled to work in the shutdown mode and the motor controller 4 is controlled to be in the current control mode. The rotor position corresponding to the measured motor 8 is set to 0° through the motor controller 4, the direct-axis current is set to the rated current, and the quadrature-axis current is set to 0. A direct current is applied to the three phases corresponding to the measured motor 8 through the motor controller 4, wherein phase A is a positive current, and phases B and C are negative currents. After the position of the measured motor 8 is stable, the resolver position sensor is read to obtain a displacement feedback value. The above steps are repeated multiple times, and the average value corresponding to the multiple displacement feedback values ​​is used as the resolver rotor position offset value corresponding to the measured motor 8. .

[0047] In this application, the rotary transformer rotor position offset value corresponding to the measured motor 8 is The measurement strategy adopts the DC positioning method, that is, the A phase input current and the BC phase output current corresponding to the measured motor 8 are set. In order to avoid the problem of unequal BC phase currents caused by different resistance drops of the two phases BC, the shaft current closed-loop control method is adopted to apply corresponding DC currents to the quadrature axis and direct axis of the measured motor.

[0048] In a specific embodiment, the bench test control system 1 has a specific measurement and control process corresponding to the resolver rotor position offset value as follows: sending a shutdown command to the dynamometer inverter 22 to control the dynamometer 21 to be in shutdown mode (not working and not providing any load torque) through the dynamometer inverter 22, sending a voltage command to the power supply module 5 to enable the power supply module 5 to provide a working voltage to the motor controller 4, controlling the motor controller 4 to be in current control mode, and sending a rotor position setting command, a direct-axis current setting command, and a quadrature-axis current setting command to the motor controller 4. After receiving the command, the motor controller 4 sets the rotor position corresponding to the motor 8 under test to 0°, the direct-axis current to the rated current of the motor, and the quadrature-axis current to 0.

[0049] At this time, a DC current is applied to the three phases of the motor 8 under test through the motor controller 4, wherein the A phase is a positive current and the BC phases are negative currents. After the position of the motor 8 under test is stable, the resolver position sensor is read to obtain a displacement feedback value. The above steps are repeated multiple times to obtain multiple displacement feedback values. The resolver rotor position offset value corresponding to the motor 8 under test is determined by taking the average of the multiple displacement feedback values. .

[0050] Taking the motor 8 under test as an example, the dynamometer 21 is placed in shutdown mode, the power supply module 5 is controlled to output a voltage of 540V, the corresponding temperature of the motor controller 4 and the motor 8 under test is stabilized at 65°C through the cooling module 7, the motor controller 4 is placed in current control mode, the rotor position corresponding to the motor 8 under test is set to 0°, the direct axis current is set to 320A, and the quadrature axis current is set to 0A through the motor controller 4, the motor 8 under test is stabilized at a fixed position after a slight rotation, and after determining that the position of the motor 8 under test is stable, the displacement feedback value fed back by the resolver position sensor is recorded, the above steps are repeated multiple times, for example 5 times, the corresponding displacement feedback values ​​are recorded, and the average value is taken as the resolver rotor position offset value .

[0051] In the present application, the resolver position sensor is arranged on the measured motor 8 to read the motor rotor position value. Under the conditions of the embodiment shown in the present application, the motor rotor position value is equal to the resolver rotor position offset value.

[0052] In a preferred embodiment, if the target motor parameters are the comprehensive resistance value, its temperature characteristics and the dead zone error voltage, the comprehensive resistance value, its temperature characteristics and the dead zone error voltage corresponding to the measured motor are determined by the following method: The command temperature of the motor environment temperature control module 6 and the cooling module 7 are set to the same given temperature; the motor controller 4 is controlled to work in the current control mode and the dynamometer module 2 is controlled to work in the shutdown mode respectively, and multiple rounds of comprehensive resistance temperature characteristic tests are started in sequence. The comprehensive resistance temperature characteristic test includes: Different direct-axis currents are applied to the motor 8 under test through the motor controller 4, and the direct-axis voltage of the motor 8 under different direct-axis currents is determined through the power acquisition instrument 3. The direct-axis voltages under different direct-axis currents are fitted to determine the comprehensive resistance and dead-zone error voltage of the motor 8 under test at the current given temperature, and the command temperature of the motor ambient temperature control module 6 and the cooling module 7 is changed to perform the next round of comprehensive resistance-temperature characteristic test.

[0053] Based on the comprehensive resistance values ​​corresponding to the measured motor 8 at different given temperatures, a comprehensive resistance-temperature characteristic curve corresponding to the measured motor 8 is established, and the comprehensive resistance-temperature characteristic curve describes the temperature characteristics corresponding to the comprehensive resistance value of the measured motor 8 .

[0054] In a specific embodiment, when measuring the comprehensive resistance value of the motor 8 under test at a given temperature T, During the process, at each given temperature T of the motor 8 under test, there are:

[0055] By applying different direct-axis currents to the motor 8 under test and substituting the above formula for multi-point voltage fitting, the corresponding comprehensive resistance value of the motor 8 under test at each given temperature T can be obtained: and dead-time error voltage .

[0056] Further, based on the comprehensive resistance corresponding to the motor 8 under test at different given temperatures T , establish temperature and comprehensive resistance The mapping relationship between them is formed to form the comprehensive resistance-temperature characteristic curve corresponding to the motor under test.

[0057] In this application, the bench test control system 1 is used for the comprehensive resistance value corresponding to the motor 8 under test. The DC current method is used to determine the temperature characteristics and dead zone error voltage of the measured motor 8. That is, the slope of the DC voltage-DC current curve corresponding to the measured resistor 8 is determined by fitting the different DC voltages and DC currents corresponding to the measured motor 8. The slope is the comprehensive resistance value corresponding to the measured motor 8 and the motor controller 4. , comprehensive resistance Including the equivalent resistance of the motor stator resistance, wire voltage drop, IGBT internal resistance and other components corresponding to the measured motor 8. The offset value between the theoretical voltage and the actual voltage is the voltage error caused by the dead zone effect. .

[0058] The bench test control system 1 is for the comprehensive resistance value corresponding to the motor 8 under test The specific process of determining the temperature characteristics and dead zone error voltage is as follows: sending a temperature instruction to the motor environment temperature control module 6 to control the environment temperature in the environment chamber 9 at a given temperature, sending a temperature instruction to the cooling module 7 to maintain the temperature of the motor 8 under test at a given temperature, and after the environment temperature stabilizes at the given temperature, sending a shutdown instruction to the dynamometer inverter 22 to put the dynamometer 21 in shutdown mode through the dynamometer inverter 22, sending a voltage instruction to the power supply module 5 to enable the power supply module 5 to provide a working voltage for the motor controller 4, controlling the motor controller 4 to be in a current control mode, and sending a direct-axis current instruction and a quadrature-axis current instruction to the motor controller 4, the direct-axis current instruction instructs the motor controller 4 to output a direct-axis current of 0 to the motor 8 under test to a motor rated current value, and the quadrature-axis current instruction instructs the motor controller 4 to output a quadrature-axis current of 0 to the motor 8 under test.

[0059] Then, multiple rounds of comprehensive resistance-temperature characteristic tests are started in sequence. The comprehensive resistance-temperature characteristic tests include: Different direct-axis currents are applied to the three phases corresponding to the motor 8 under test by the motor controller 4, and the direct-axis voltage of the motor controller 4 under different direct-axis currents is determined by the power acquisition instrument 3. The comprehensive resistance value corresponding to a given temperature is determined by linear fitting of different direct-axis currents and direct-axis voltages. And the dead zone error voltage Verror, then change the command temperature of the motor environment temperature control module 6 and the cooling module 7 and perform the next round of comprehensive resistance temperature characteristic test.

[0060] The dead-zone error voltage Verror can be obtained by performing difference processing on the direct-axis voltage determined by the power collector 3 under different direct-axis currents and the direct-axis voltage corresponding to the measured motor 8 fed back by the motor controller 4. It should be noted that the dead-zone error voltage Verror is affected by the software and hardware characteristics of the motor controller 4 and has nothing to do with the characteristics of the measured motor 8. Therefore, when the motor controller 4 is replaced, the dead-zone error voltage Verror needs to be remeasured.

[0061] Taking the motor 8 under test as an example, the bench test control system 1 sends a temperature command of 65°C to the motor environment temperature control module 6 and the cooling module 7, controls the dynamometer 21 to be in shutdown mode, controls the power supply module 5 to provide a 540V working voltage to the motor controller 4, controls the motor controller 4 to be in current control mode, and controls the quadrature axis current of the motor 8 under test to 0A through the motor controller 4, and starts multiple rounds of comprehensive resistance-temperature characteristic tests in sequence. The comprehensive resistance-temperature characteristic tests include: controlling the direct axis current of the motor 8 under test to 100A, 150A, 200A, 250A, and 300A in sequence through the motor controller 4, collecting the AB phase voltage and AC phase voltage corresponding to the motor 8 under test through the power acquisition instrument 3, and then calculating different direct axis currents. The corresponding direct axis voltage , combined with the direct axis voltage and current, the comprehensive resistance corresponding to the measured motor 8 and the motor controller 4 at 65°C is obtained by fitting is 0.025Ω, and the dead zone error voltage Verror is 10.75V.

[0062] Change the command temperature of the motor environment temperature control module 6 and the cooling module 7, and conduct the next round of comprehensive resistance temperature characteristic test. The comprehensive resistance value corresponding to the tested motor 8 obtained by the comprehensive resistance temperature characteristic test of the tested motor 8 at different given temperatures is , establish the comprehensive resistance-temperature characteristic curve corresponding to the motor 8 under test.

[0063] In the prior art, there are two main methods for measuring the inductance parameters of permanent magnet synchronous motors: (1) instrument measurement: generally, an LCR tester is used to measure the motor inductance; (2) special working condition identification: mainly a pulse voltage test method is used. When using an LCR tester to measure the motor inductance, one phase of the stator winding must be disconnected and the inductance between the other two phases must be measured. In order to obtain the AC and DC axis inductance parameter values ​​of the motor, the measured inductance must also be converted. The conversion formula is related to the motor rotor position angle, and the conversion formula is different for permanent magnet motors with different magnetic circuits, which undoubtedly complicates the measurement process.

[0064] The pulse voltage test method changes the connection mode of the three-phase winding of the motor, applies a DC pulse voltage when the rotor is in the direct-axis and quadrature-axis positions, records the current, and then uses the integral method to respectively calculate the direct-axis inductance and the quadrature-axis inductance. When measuring the inductance by the pulse voltage test method, the voltage amplitude and the action time must be accurately selected. If the voltage amplitude is too small, the detection accuracy will be affected. If the voltage amplitude is too large, the current may exceed the limit of the special device and affect the safety of the special device. If the action time is too short, there will be few sampling points and little current information obtained, which will also affect the detection accuracy. If the action time is too long, the current may also be too large and affect the safety of the controller. Therefore, the operability of the pulse voltage test method is poor. More importantly, affected by the magnetic saturation and cross-magnetic saturation of the magnetic circuit, the inductance parameters are not the same under different excitation intensities, that is, under different direct and quadrature-axis current conditions, which makes it more difficult to obtain accurate inductance parameters.

[0065] In a preferred embodiment, if the target motor parameters are the direct-axis inductance matrix and the quadrature-axis inductance matrix, the direct-axis inductance matrix and the quadrature-axis inductance matrix corresponding to the motor 8 under test are determined in the following manner: The command temperatures of the motor ambient temperature control module 6 and the cooling module 7 are set to the same given temperature, the motor controller 4 is controlled to work in the current control mode, the dynamometer module 2 is controlled to work in the speed control mode to drag the motor 8 under test to a given speed, and the power supply module 5 is controlled to provide the motor controller 4 with a working voltage.

[0066] Furthermore, different shaft currents are applied to the motor 8 under test in sequence through the motor controller 4, and the shaft currents include direct-axis current and quadrature-axis current. Under each set of shaft currents, the following operations are performed: the direct-axis voltage and quadrature-axis voltage corresponding to the motor 8 under test are determined through the power acquisition instrument 3; the direct-axis current, quadrature-axis current, direct-axis voltage, quadrature-axis voltage, motor speed, and rotor permanent magnet flux linkage and comprehensive resistance of the motor 8 under test at a given temperature are determined according to the direct-axis current, quadrature-axis current, direct-axis voltage, quadrature-axis voltage, motor speed corresponding to the set of shaft currents, and the shaft voltage equation corresponding to the motor 8 under test are combined to determine the direct-axis inductance and quadrature-axis inductance of the motor 8 under the set of shaft currents; a direct-axis inductance matrix and a quadrature-axis inductance matrix are formed according to the direct-axis inductance and quadrature-axis inductance corresponding to the motor 8 under each set of shaft currents.

[0067] In another preferred embodiment, the axis voltage equation includes a direct axis voltage equation and a quadrature axis voltage equation, wherein the direct axis voltage equation is:

[0068] in, represents the direct axis voltage determined by the power collector 3, Indicates the comprehensive resistance of the motor under test at a given temperature. represents the direct axis current, represents the direct-axis inductance, represents the voltage frequency corresponding to the measured motor 8 determined by the power collector 3, represents the quadrature-axis inductance, Indicates the quadrature axis current.

[0069] The quadrature axis voltage equation is:

[0070] represents the quadrature axis voltage determined by the power collector 3, It represents the rotor permanent magnet flux of the motor 8 under test at a given temperature.

[0071] , The actual direct-axis voltage and the actual quadrature-axis voltage are collected by the power collector 3 and obtained after filtering and calculation processing, thereby avoiding the phenomenon that the command voltage is used to cause an error between the command voltage and the actual output voltage.

[0072] The direct-axis current provided by the motor controller 4 With quadrature axis current Under stable conditions, the differential term in the above formula can be equivalent to 0, and different direct-axis currents can be obtained based on the above axis voltage equation. With quadrature axis current The direct-axis inductance matrix and the quadrature-axis inductance matrix formed below.

[0073] See also Figure 3 , Figure 3 A current test grid diagram for measuring the inductance matrix of a motor under test provided in an embodiment of the present application is shown.

[0074] Taking the motor 8 under test as an example, for the bench test control system 1, the following are executed: the power supply module 5 is controlled to provide a 540V working voltage to the motor controller 4, the ambient temperature and the corresponding temperature of the motor 8 under test are maintained at 65°C through the motor ambient temperature control module 6 and the cooling module 7, the dynamometer inverter 22 is in the speed control mode and the corresponding speed of the dynamometer 21 is set to 500rpm, and the current control mode and current command are sent to the motor controller 4 under test, wherein, according to the following Figure 3 The current grid shown in FIG. 1 outputs the corresponding direct-axis current and quadrature-axis current to the motor 8 under test, such as Figure 3 As shown, the horizontal axis represents the direct axis current (in ampere A), and the vertical axis represents the quadrature axis current (in ampere A).

[0075] like Figure 3 As shown, the radius of the current limit circle is 900A, and the quadrature axis current and direct axis current grids are divided into units of 30A. Figure 3 There are a total of 737 current grid points in the current limit circle shown. The motor controller 4 is controlled to output the quadrature-axis current and direct-axis current corresponding to the 737 current grid points in sequence. For each current grid point, after the quadrature-axis and direct-axis of the motor 8 under test reach the quadrature-axis current and direct-axis current corresponding to the current grid point and stabilize, the actual direct-axis voltage and quadrature-axis voltage corresponding to the motor 8 under test are determined by the power acquisition instrument 3, combined with the motor speed, the rotor permanent magnet flux Ψf of the motor under test at a given temperature, and the comprehensive resistance value. , so as to solve the direct-axis inductance and quadrature-axis inductance. After all current grid points are measured, the direct-axis inductance and quadrature-axis inductance corresponding to the motor under test are determined by linear fitting.

[0076] Specifically, the power collector 3 collects the current and voltage corresponding to the measured motor 8. By collecting the three-phase current of the motor and the quadrature-axis current and direct-axis current fed back by the motor controller, the collected three-phase voltage can be subjected to Clarke and Park transformation to obtain the actual direct-axis voltage and quadrature-axis voltage.

[0077] Specifically, under each set of shaft currents, in order to ensure the current control performance of the motor controller 4, the operating speed of the motor 8 under test and the motor controller 4 should be less than the rated speed, the bus voltage is close to the rated voltage, and the quadrature axis current and the direct axis current are traversed through the current grid within the maximum current limit circle, and then the DC inductance matrix is ​​determined by fitting. and AC inductance matrix .

[0078] See also Figure 4 , Figure 4 FIG. 2 shows a direct-axis inductor matrix provided by an embodiment of the present application. Figure 4 As shown, the quadrature axis current corresponding to the motor 8 under test is , direct axis current and direct-axis inductance Establish the corresponding spatial mapping relationship to form Figure 4 The direct-axis inductance matrix shown .

[0079] See also Figure 5 , Figure 5 FIG. 1 shows a cross-axis inductor matrix provided by an embodiment of the present application. Figure 5 As shown, the quadrature axis current corresponding to the motor 8 under test is , direct axis current and quadrature axis inductance Establish the corresponding spatial mapping relationship to form Figure 5 The quadrature-axis inductance matrix shown .

[0080] In the present application, the bench test control system 1 runs any of the steps provided in the above embodiments. Specifically, according to the motor parameter measurement instruction obtained from the host computer, the dynamometer 21 is controlled to operate in speed control mode or shutdown mode, and the motor torque and motor speed corresponding to the motor under test 8 fed back by the torque measurement shaft are collected. The voltage amplitude, voltage frequency, current amplitude and current frequency corresponding to the motor under test 8 are determined through the power acquisition instrument 3, and an output voltage command value or a circuit breaker command is sent to the power supply module 5. The motor controller 4 is controlled to operate in shutdown mode or current control mode, and a temperature control command is sent to the cooling module 7. The temperature in the environmental chamber 9 is controlled through the environmental temperature control module 6. Dynamometer module 2: The dynamometer inverter 22 is used to operate in speed control mode, stop mode or torque control mode according to the control instructions issued by the bench test control system 1. In the speed control mode, the output speed of the dynamometer 21 is maintained at the given speed issued by the bench test control system 1. In the torque control mode, the output torque of the dynamometer 21 is maintained at the given torque issued by the bench test control system 1. In the stop mode, the corresponding output of the dynamometer 21 is stopped.

[0081] Specifically, the dynamometer inverter 22 controls the speed and torque of the motor 8 under test in combination with the dynamometer 21 according to the control instructions issued by the bench test control system 1. Generally, the power and speed of the dynamometer 21 are larger than those of the motor 8 under test, thereby ensuring control accuracy and system safety. The motor 8 under test is driven by the dynamometer and can operate under different speed and torque conditions.

[0082] The motor controller 4 is used to operate in a stop mode or a current control mode according to the control instructions issued by the bench test controller system 1 .

[0083] Specifically, the motor controller 4 applies a controllable PWM voltage to put the motor 8 under test into the stop mode or the current control mode.

[0084] Among them, the tested motor 8 and the motor controller 4 are both the tested objects corresponding to the present application. The tested motor 8 and the motor controller 4 can be the same tested object integration formed by matching each other, or they can be independent devices that do not match each other. If the tested motor 8 and the motor controller 4 are independent devices that do not match each other, a CAN bus or other types of communication methods are required between the tested motor 8 and the motor controller 4, and between the motor controller 4 and the bench test control system. The motor controller 4 needs to open the shutdown interface, current control interface and rotary transformer calibration interface.

[0085] The power supply module 5 is used to output a controllable DC voltage or disconnect its own output from the motor controller according to the control instructions issued by the bench test control system 1; The power supply module 5 can be a battery simulator or a DC power supply, which provides a high-voltage voltage source for the motor 8 under test and the motor controller 4. After being driven, the power supply module 5 outputs power to the motor controller 4. During braking, the power supply module 5 recovers the braking energy and feeds it back to the power grid, ensuring the stability of the input voltage of the object under test (motor controller 4 and motor 8 under test).

[0086] The motor environment temperature control module 6 is used to control the temperature in the environment chamber 9 under the control instructions issued by the bench test control system 1.

[0087] The cooling module 7 is used to cool the motor under test 8 and the motor controller 4 under the control instruction issued by the bench test control system 1.

[0088] Specifically, the resistance parameters and rotor permanent magnet flux Ψf corresponding to the measured motor 8 are significantly affected by temperature. In order to ensure the stability of the resistance parameters and rotor permanent magnet flux Ψf during the measurement process, improve the measurement accuracy, and obtain the temperature characteristics of such parameters, it is necessary to control the temperature corresponding to the measured motor 8 during the measurement of such parameters. The temperature control of the measured motor 8 is divided into two parts: ambient temperature control and heat dissipation temperature control.

[0089] Ambient temperature control is achieved through the motor ambient temperature control module 6. The motor 8 under test needs to be installed in the environmental chamber 9 corresponding to the motor ambient temperature control module 6. The motor ambient temperature control module 6 adjusts the corresponding ambient temperature in the environmental chamber 9 under the control of the bench test control system 1, so that the ambient temperature of the motor 8 under test can be controlled under different parameter measurement conditions, so as to test the motor parameter change characteristics of the motor under different temperature conditions.

[0090] The cooling module 7 is a heat exchange module. The cooling medium of the tested motor 8 and the motor controller 4 is mostly a mixture of 50% ethylene glycol and 50% water. The cooling medium of the test bench is mostly 25° cooling water or 0° chilled water. Heat exchange is required between the two cooling media, and the flow rate must be controllable.

[0091] The cooling module 7 is used to cool the motor under test 8 and the motor controller 4, and automatically adjusts the cooling flow according to the temperature control instructions of the motor under test 8 and the motor controller 4 issued by the bench test control system 1 to maintain the temperature of the motor under test 8 and its motor controller 4 constant.

[0092] The power collector 3 is used to collect the PWM modulated voltage signal applied by the motor controller 4 to the winding of the motor 8 under test, or the back electromotive force voltage signal generated when the motor 8 under test rotates passively, and collect the current signal in the winding of the motor 8 under test through the current sensor, and transmit the processed voltage and current data to the bench test control system 1.

[0093] In a specific embodiment, the motor controller 4, based on the control instructions issued by the bench test control system 1, inverts the DC high voltage, applies the impulse equality principle, and applies a PWM voltage that is equivalent to a sinusoidal voltage to the motor 8 under test, so that the motor 8 under test generates a three-phase current. The motor controller 4 realizes the controllable torque or speed of the motor 8 under test. However, the PWM voltage is a high-frequency and high-voltage signal, which cannot be directly collected by the bench test control system 1. The PWM voltage needs to be low-pass filtered by the power collector 3 to extract the fundamental component, and then it is converted into a voltage signal that can be collected by the bench test control system 1 through isolation and voltage division. Due to the use of the low-pass filter, the amplitude and angle of the collected fundamental voltage will be different from the actual value. Therefore, the bench test control system 1 needs to compensate according to the filter characteristics in the power collector 3.

[0094] The power collector 3 includes a voltage collection module and a current collection module. The voltage collection module is responsible for collecting any two corresponding voltages and currents of the motor 8 under test. After dividing the collected sinusoidal back electromotive force voltage and transforming the waveform, it outputs the sinusoidal voltage and square wave voltage that can be collected by the bench test control system 1 to the bench test control system 1 for further calculation of the voltage amplitude and voltage frequency, or directly calculates the voltage frequency and voltage amplitude corresponding to the back electromotive force and feeds them back to the bench test control system 1. For the voltage after PWM modulation, the power collector 3 performs a low-pass filter on it, and the fundamental voltage of the output sinusoidal waveform is collected by the voltage collection module. The current of the motor 8 under test is collected by the current collection module and output to the bench test control system 1.

[0095] The benefits of this application are: By making full use of the traditional dynamometer bench, performing a small amount of equipment technology upgrades and combining the motor parameter automatic measurement method provided in this application, the permanent magnet synchronous motor system (permanent magnet synchronous motor under test and its corresponding motor controller) can be fully automatically measured for the main motor parameters. Based on different measurement strategies corresponding to different motor parameters, the automatic measurement of different motor parameters can be achieved. The permanent magnet synchronous motor parameters measured by the method of the present invention are used to establish a permanent magnet synchronous motor simulation and control model, which can be well applied to various development links based on the V process to improve simulation accuracy and development efficiency.

[0096] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working process of the system and device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here. In the several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0097] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0098] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0099] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program codes.

[0100] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for automatically measuring motor parameters, characterized in that: A bench test control system applied to an automatic motor parameter measurement system, wherein the automatic motor parameter measurement system further comprises a plurality of measurement modules, wherein the plurality of measurement modules comprises a dynamometer module, a power acquisition instrument, a motor controller, a power supply module, a motor environment temperature control module and a cooling module. The motor under test is placed in the environmental chamber, the bench test control system is connected to the multiple measurement modules respectively, the motor under test is connected to the power collector, the dynamometer module and the motor controller respectively, the power collector is also connected to the motor controller, the motor controller is connected to the power supply module, the motor controller and the motor under test are also connected to the cooling module respectively, and the motor under test is connected to the dynamometer module through the torque measurement shaft. Wherein, the method comprises: receiving a target motor parameter measurement instruction, wherein the target motor parameter measurement instruction indicates a target motor parameter to be measured; According to the target motor parameter determination instruction, a target determination strategy corresponding to the target motor parameter is determined, wherein the target determination strategy describes at least one target determination module and a target determination control method required for mobilizing and controlling the target motor parameter; The at least one target determination module is controlled according to the target determination control mode to determine the target motor parameter corresponding to the motor under test.

2. The method according to claim 1, characterized in that If the target motor parameter is the number of motor pole pairs, the number of motor pole pairs corresponding to the motor under test is determined by: Controlling the motor controller to operate in a stop mode; Controlling the dynamometer module to operate in a speed control mode and driving the motor under test to a given speed; Collecting the back electromotive force signal corresponding to the motor under test by a power collector and obtaining the voltage frequency of the power collector based on the back electromotive force signal feedback; The ratio between the voltage frequency and the given rotation speed is determined as the number of motor pole pairs corresponding to the measured motor.

3. The method according to claim 1, characterized in that If the target motor parameter is the rotor permanent magnet flux and its temperature characteristics, the rotor permanent magnet flux and its temperature characteristics corresponding to the motor under test are measured in the following manner: The command temperatures of the motor ambient temperature control module and the cooling module are set to the same given temperature; Control the motor controller to be in stop mode; Control the dynamometer module to be in speed control mode and drag the motor under test to a given speed; The test of the temperature characteristic of the magnetic flux of multiple rotor permanent magnets is started in sequence. The test of the temperature characteristic of the magnetic flux of the rotor permanent magnets comprises: collecting the back electromotive force signal between any two phases of the motor under test by a power acquisition instrument, and determining the magnetic flux of the rotor permanent magnet of the motor under test at a current given temperature according to the back electromotive force signal; Changing the command temperature of the motor environment temperature control module and the cooling module and performing the next round of rotor permanent magnet flux temperature characteristic test; Based on the rotor permanent magnet flux corresponding to the motor under test at different given temperatures, a rotor permanent magnet flux temperature characteristic curve corresponding to the motor under test is established, wherein the rotor permanent magnet flux temperature characteristic curve describes the temperature characteristics corresponding to the rotor permanent magnet flux corresponding to the motor under test.

4. The method according to claim 3, characterized in that The rotor permanent magnet flux of the motor under test at each ambient temperature is determined by the following formula: In this formula, represents the rotor permanent magnet flux, Indicates the voltage amplitude determined by the power harvester based on the back EMF signal. represents the given speed, and P represents the number of motor pole pairs.

5. The method according to claim 1, characterized in that If the target motor parameter is a resolver rotor position offset value, the resolver rotor position offset value corresponding to the measured motor is determined by: S1, respectively controlling the dynamometer module to operate in a shutdown mode and controlling the motor controller to operate in a current control mode; S2, setting the rotor position corresponding to the measured motor to 0°, the direct-axis current to the rated current, and the quadrature-axis current to 0 by means of the motor controller; S3, applying direct current to the three phases corresponding to the motor under test through the motor controller, wherein phase A is a positive current, and phases B and C are negative currents; S4, after the position of the motor under test is stable, read the resolver position sensor to obtain the displacement feedback value; Repeat steps S1 to S4 multiple times; The average value corresponding to the multiple displacement feedback values ​​is used as the resolver rotor position offset value corresponding to the measured motor.

6. The method according to claim 1, characterized in that If the target motor parameters are the comprehensive resistance value, its temperature characteristics and the dead zone error voltage, the comprehensive resistance value, its temperature characteristics and the dead zone error voltage corresponding to the measured motor are determined by the following method: The command temperatures of the motor ambient temperature control module and the cooling module are set to the same given temperature; Respectively controlling the motor controller to work in a current control mode and controlling the dynamometer module to work in a shutdown mode; Start multiple rounds of comprehensive resistance-temperature characteristic tests in sequence. The comprehensive resistance-temperature characteristic tests include: Applying different direct-axis currents to the motor under test through the motor controller; Determine the direct-axis voltage of the motor under test at different direct-axis currents by means of the power acquisition instrument; Fitting the direct-axis voltages under different direct-axis currents to determine the comprehensive resistance and dead-zone error voltage of the motor under test at a current given temperature; Changing the command temperature of the motor environment temperature control module and the cooling module and performing the next round of comprehensive resistance temperature characteristic test; Based on the comprehensive resistance values ​​corresponding to the measured motor at different given temperatures, a comprehensive resistance-temperature characteristic curve corresponding to the measured motor is established, wherein the comprehensive resistance-temperature characteristic curve describes the characteristic of the comprehensive resistance value corresponding to the measured motor changing with temperature.

7. The method according to claim 1, characterized in that If the target motor parameters are a direct-axis inductance matrix and a quadrature-axis inductance matrix, the direct-axis inductance matrix and the quadrature-axis inductance matrix corresponding to the motor under test are measured in the following manner: The command temperatures of the motor ambient temperature control module and the cooling module are set to the same given temperature; Controlling the motor controller to operate in a current control mode; Controlling the dynamometer module to operate in a speed control mode to drive the motor under test to a given speed; Applying different shaft currents to the motor under test in sequence through a motor controller, wherein the shaft currents include a direct-axis current and a quadrature-axis current; Under each set of shaft currents, the following steps are performed: determining the direct-axis voltage and quadrature-axis voltage corresponding to the motor under test by means of a power acquisition instrument; According to the direct-axis current, quadrature-axis current, direct-axis voltage, quadrature-axis voltage, motor speed corresponding to the set of shaft currents, and the rotor permanent magnet flux and comprehensive resistance of the motor under test at the given temperature, combined with the shaft voltage equation corresponding to the motor under test, determine the direct-axis inductance and quadrature-axis inductance of the motor under test under the set of shaft currents; According to the direct-axis inductance and quadrature-axis inductance corresponding to each set of shaft currents of the measured motor, a direct-axis inductance matrix and a quadrature-axis inductance matrix are formed.

8. The method according to claim 7, characterized in that The axis voltage equation includes a direct axis voltage equation and a quadrature axis voltage equation. The direct axis voltage equation is: in, represents the direct-axis voltage determined by the power acquisition instrument, It indicates the comprehensive resistance value of the motor under test at the given temperature. represents the direct axis current, represents the direct-axis inductance, Indicates the voltage frequency corresponding to the motor under test determined by the power acquisition instrument. represents the quadrature-axis inductance, represents the quadrature axis current; The quadrature axis voltage equation is: in, represents the quadrature axis voltage determined by the power acquisition instrument, It represents the rotor permanent magnet flux of the motor under test at a given temperature.

9. A motor parameter automatic measurement system, characterized in that: The motor parameter automatic measurement system includes a bench test control system, a dynamometer module, a power acquisition instrument, a motor controller, a power supply module, a motor environment temperature control module and a cooling module. Wherein, the bench test control system is applied to the motor parameter automatic measurement method provided in any one of claims 1 to 8 above; The dynamometer module is used to operate in a speed control mode or a shutdown mode according to a control instruction issued by the bench test control system; A motor controller, used to operate in a stop mode or a current control mode according to a control instruction issued by a bench test controller system; A power supply module is used to output a controllable DC voltage or disconnect its own output from the motor controller according to the control instructions issued by the bench test control system; The motor environment temperature control module is used to control the temperature in the environment chamber under the control instructions issued by the bench test control system; A cooling module is used to cool the motor under test and its corresponding motor controller, and automatically adjusts the cooling flow rate according to the temperature control instructions of the motor and controller issued by the bench test control system to maintain a constant temperature of the motor under test and its corresponding motor controller; The power collector is used to collect the PWM modulated voltage signal applied by the motor controller to the motor winding under test, or the back electromotive force voltage signal generated when the motor rotates passively, and collect the current signal in the motor winding under test through the current sensor, and transmit the processed voltage and current data to the bench test control system.

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