Method for configuring the current of an electric machine in full state

Abstract

The application relates to a method for configuring current of an electric machine in a full-load state, which comprises the following steps: receiving a target torque sent by a vehicle controller, wherein the target torque is smaller than the maximum value of the electric machine torque; obtaining an initial value of a target current according to the target torque; and obtaining the target current of the electric machine in a dynamic coordinate system according to the initial value of the target current and a preset boundary condition strategy, wherein the target current comprises a target excitation current and a target torque current. The application specifically divides the working conditions of the electric machine in the full-load state for configuring the target current through the preset boundary condition strategy, so that the original allocation value of the target current can be reconfigured in any working condition of the electric machine, and then the target excitation current and the target torque current can be accurately obtained.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of motor control, in particular to a method for configuring current of a motor in full capacity state. BACKGROUND

[0002] In the prior art, the control method of an induction motor is usually field-oriented vector control, which has the characteristics of fast torque response, high steady-state accuracy and small torque ripple.

[0003] The field-oriented vector control scheme usually indirectly obtains the magnetic field position through stator frequency integration or flux linkage observer, and obtains target torque current and target excitation current through the solution of the target torque requested by the vehicle control unit (VCU), and then realizes indirect control of torque by using a proportional integral controller (PIC). If the maximum value of the motor torque during the operation of the motor can meet the target torque requested by the vehicle control unit, the motor can output according to the target torque requested by the vehicle control unit, and at this time the working state of the motor can be called "full capacity state". However, the control scheme in the prior art has the problem that the target torque current and the target excitation current cannot be accurately obtained when the motor is in full capacity state. SUMMARY

[0004] Therefore, the present application provides a method for configuring current of a motor in full capacity state to solve the problem that the target torque current and the target excitation current cannot be accurately obtained when the motor is in full capacity state in the prior art.

[0005] The present application provides a method for configuring current of a motor in full capacity state, comprising:

[0006] receiving a target torque sent by a vehicle control unit, the target torque being less than the maximum value of the motor torque;

[0007] obtaining an initial value of a target current according to the target torque;

[0008] obtaining the target current of the motor in a dynamic coordinate system according to the initial value of the target current and a preset boundary condition strategy, wherein the target current includes a target excitation current and a target torque current.

[0009] In one embodiment, receiving a target torque sent by a vehicle control unit, previously comprises:

[0010] obtaining motor parameters, the motor parameters including bus voltage U dc , synchronous angular velocity ω s , leakage coefficient σ and stator inductance L s ;

[0011] obtaining the maximum allowable phase current I of the motor max and the rated excitation current I sdrate ;

[0012] The mathematical expression of the boundary condition strategy is:

[0013] and I sdref ≤ I sdrate

[0014] wherein, I sdref and I sqref are initial values of the target current;

[0015] When the boundary condition strategies are all satisfied, the target current of the motor in the dynamic coordinate system is configured to be equal to the initial value I sdref

[0016] In one embodiment, the target torque sent by the vehicle controller is received, and before that, the following steps are included:

[0017] obtaining motor parameters, the motor parameters including bus voltage U dc , synchronous angular velocity ω s , leakage coefficient σ and stator inductance L s ;

[0018] obtaining the maximum allowable phase current I of the motor max and the rated excitation current I sdrate ;

[0019] The mathematical expression of the boundary condition strategy is:

[0020] and I sdref >I sdrate

[0021] wherein, I sdref and I sqref are initial values of the target current;

[0022] When the boundary condition strategies are all satisfied, the target excitation current I sd is configured to be equal to the rated excitation current I sdrate , and the target torque current I sd is obtained according to the target torque and the target excitation current I sq , and the target current configured at the same time satisfies the mathematical expression: and

[0023] In one of the embodiments, the target torque sent by the whole vehicle controller is received, and the target torque includes:

[0024] The motor parameters are obtained, and the motor parameters include bus voltage U dc , synchronous angular velocity ω s , leakage coefficient σ and stator inductance L s ;

[0025] The maximum allowable phase current I max and the rated excitation current I sdrate of the motor are obtained;

[0026] The mathematical expression of the boundary condition strategy is:

[0027]

[0028] Wherein, I sdref and I sqref are initial values of the target current;

[0029] When the boundary condition strategy is satisfied, the slip frequency obtained by obtaining the original allocation value of the target current is stepped up, and the solution value I sd_k , I sq_k of the target current is obtained according to the target torque and the slip frequency;

[0030] If the solution value I sd_k , I sq_k of the target current satisfies the mathematical expression: The target current I sd , I sq is configured to be equal to the solution value I sd_k , I sq_k of the target current, and the configured target current satisfies the mathematical expression: And

[0031] In one of the embodiments, when the initial value of the target current is obtained according to the target torque, the assumption condition that the target excitation current is equal to the target torque current is proposed.

[0032] In one of the embodiments, the mathematical expression for obtaining the initial value of the target current is:

[0033]

[0034] Wherein, I sdref , I sqref are initial values of the target current, N p is the number of motor pole pairs, I m is the motor excitation mutual inductance, and Lr is the rotor inductance.

[0035] In one of the embodiments, the maximum allowed phase current is obtained according to a method of electromagnetic simulation test.

[0036] In one of the embodiments, the rated excitation current is obtained according to rated parameters of the motor, the rated parameters including rated voltage, rated current, rated frequency, rated slip frequency, rated rotating speed.

[0037] The application specifically divides the working conditions of the target current of the motor in the full-load state by the preset boundary condition strategy, so that the original allocation value of the target current can be reconfigured in any of the working conditions of the motor, and then the target torque current and the target excitation current can be accurately obtained. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 The flowchart of the steps for obtaining the actual current of the motor provided by one of the embodiments of the application;

[0039] Figure 2 The flowchart of the steps for obtaining the voltage of the motor in the stationary coordinate system provided by one of the embodiments of the application;

[0040] Figure 3 The schematic diagram of the working conditions of the target current divided by one of the embodiments of the application;

[0041] Figure 4 The flowchart of the method for configuring the current of the motor in the full-load state provided by one of the embodiments of the application. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions and advantages of the application clearer, the application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the application and not to limit the application.

[0043] It should be noted that the diagrams provided in the embodiments only illustrate the basic concept of the application in a schematic manner.

[0044] The structures, proportions, sizes, etc. shown in the drawings of the specification are only used to cooperate with the content disclosed in the specification, so that those skilled in the art can understand and read, and are not used to limit the defined conditions under which the application can be implemented. Any modification of the structure, change of the proportion relationship or adjustment of the size, which does not affect the effect that can be produced by the application and the purpose that can be achieved, should still fall within the scope of the technical content disclosed by the application.

[0045] The orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "intermediate", "vertical", "horizontal", "horizontal", "inner", "outer", "radial", "circumferential" and the like as used in this specification are based on the orientations or positional relationships shown in the drawings, and are merely intended to simplify the description and are not indicative of or suggestive of the orientations in which the devices or elements must be constructed and operated, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second" are only used for descriptive purposes and cannot be understood as indicating or suggesting relative importance.

[0046] Before the motor configures the target current in the dynamic coordinate system in the full state, the actual current of the motor in the dynamic coordinate system is obtained, wherein the actual current includes the actual excitation current and the actual torque current.

[0047] Then, the method for configuring the current of the motor in the full state provided by the present application is used to obtain the target current of the motor in the dynamic coordinate system.

[0048] Subsequently, the target current of the motor in the dynamic coordinate system and the actual current are subtracted and processed by proportion integration to obtain the target modulation voltage of the motor in the dynamic coordinate system, and the target modulation voltage of the motor in the static coordinate system and the rotor flux position are inversely Park transformed to obtain the target modulation voltage of the motor in the static coordinate system.

[0049] After that, the target modulation voltage of the motor in the static coordinate system is subjected to space vector modulation processing to obtain the three-phase pulse signal of the motor, which is output to the inverter for driving the motor, thereby achieving the purpose of field-oriented vector control of the motor.

[0050] As shown in Figure 1 The actual step of obtaining the actual current of the motor in the dynamic coordinate system can be step S1, which includes:

[0051] S101: presetting the mapping relationship of the stator current amplitude of the motor and the stator leakage inductance, the motor torque and the rotor leakage inductance, and the air gap flux and the excitation mutual inductance;

[0052] S102: collecting the three-phase current, bus voltage, stator temperature and rotor position of the motor;

[0053] S103: performing voltage reconstruction and Clarke transformation on the bus voltage to obtain the voltage of the motor in the static coordinate system;

[0054] S104: performing Clarke transformation on the three-phase current to obtain the current of the motor in the static coordinate system, and further obtaining the stator current amplitude;

[0055] S105: obtaining the stator resistance of the motor according to the temperature of the stator;

[0056] S106: Obtain the motor speed based on the rotor position;

[0057] S107: Based on the voltage and current of the motor in the stationary coordinate system, the stator resistance, the speed, and the stator leakage inductance, rotor leakage inductance, and excitation mutual inductance obtained in the previous control cycle, the flux linkage is observed to obtain the motor torque, air gap flux linkage, and rotor flux linkage position in the current control cycle. In the first control cycle of the motor, the stator leakage inductance, rotor leakage inductance, and excitation mutual inductance are all preset values.

[0058] S108: Reacquire the stator leakage inductance, rotor leakage inductance and excitation mutual inductance of the motor according to the mapping relationship, so as to obtain the motor torque, air gap flux linkage and rotor flux linkage position of the motor in the next control cycle.

[0059] S109: Perform Parker transformation on the motor current in the stationary coordinate system based on the rotor flux linkage position to obtain the actual current of the motor in the dynamic coordinate system.

[0060] In this embodiment, by way of example, the dynamic coordinate system can be a multi-dimensional coordinate system, such as a two-phase rotating coordinate system; the static coordinate system can be a multi-dimensional coordinate system, such as a two-phase stationary coordinate system.

[0061] In step S101, it is illustrated by way of example that the preset mapping relationship can be a parameter lookup table, which can be obtained through electromagnetic simulation experiments. It is understood that the mapping relationship is determined by the stator current amplitude I. amp The stator leakage inductance L can be obtained by looking up a table. ls Through the motor torque T e The rotor leakage inductance L can be obtained by looking up a table. lr Through air gap magnetic flux The excitation mutual inductance L can be obtained by looking up a table. m .

[0062] In step S102, it is illustrated by way of example that the three-phase current I of the motor can be acquired by a current sensor. A I B I C The motor bus voltage U can also be acquired through a voltage sensor. dc Furthermore, the stator temperature of the motor can be collected through a temperature sensor, and the rotor position of the motor can be collected through a rotary transformer.

[0063] like Figure 2 As shown, step S103 above, which involves voltage reconstruction and Clarke transformation of the bus voltage to obtain the motor voltage in the stationary coordinate system, includes:

[0064] S1031: Obtain three-phase pulse signals of the motor in a previous control period, wherein the three-phase pulse signals are preset values in a first control period of the motor;

[0065] S1032: Perform voltage reconstruction according to the bus voltage and the three-phase pulse signals to obtain three-phase voltages of the motor;

[0066] S1033: Perform Clarke transformation on the three-phase voltages to obtain voltages of the motor in a stationary coordinate system.

[0067] In step S1031, it is exemplarily illustrated that obtaining the three-phase pulse signals of the motor in the previous control period refers to obtaining three-phase pulse signals t A , t B , t C transmitted to the inverter by the motor in the previous control period. A B C In the first control period of the motor, the preset values of the three-phase pulse signals t A , t B , t C may be 0 or 0.5, for example, t A = 0, t B = 0.5, t C = 0.5; or t A = 0.5, t B = 0, t C = 0.5, etc.

[0068] In step S1032, it is exemplarily illustrated that the mathematical expression of the voltage reconstruction can be:

[0069]

[0070] wherein U A , U B , U C are the three-phase voltages.

[0071] In step S1033, it is exemplarily illustrated that, after obtaining the three-phase voltages U A , U B , U C of the motor, performing Clarke transformation on the three-phase voltages can obtain voltages U sα , U sβ of the motor in the two-phase stationary coordinate system.

[0072] In step S104, it is exemplarily illustrated that performing Clarke transformation on the three-phase currents I A , I B , I C can obtain I sα , I sβ of the motor in the two-phase stationary coordinate system, and obtain the stator current amplitude I ampThe mathematical expression of the stator resistance can be:

[0073]

[0074] In step S105, the mathematical expression of the stator resistance of the motor according to the temperature of the stator can be:

[0075] R sm = R s0 (1 + K s (t m -t0))

[0076] where t m is the current temperature value, R sm is the stator resistance at temperature t m , t0 is the initial temperature value, R s0 is the stator resistance at temperature t0, and K s is the temperature coefficient of the material of the stator.

[0077] In step S106, the motor speed can be obtained according to the position change of the rotor within a fixed time, and the specific mathematical expression is:

[0078]

[0079] where n is the speed, ΔT is the fixed time, and ΔP is the position difference of the motor within the fixed time, which can be obtained by the collected rotor position.

[0080] It can be understood that the above steps S103-S106 can be performed synchronously, and the sequential arrangement in steps is only for the convenience of description.

[0081] In step S107, the flux linkage observer can be observed according to the voltage U sα , U sβ and current I sα , I sβ , stator resistance R s , speed n, and stator leakage inductance L ls , rotor leakage inductance L lr and excitation mutual inductance L m in the previous control period, to obtain the motor torque T e , air gap flux linkage and rotor flux linkage position

[0082] The mathematical model of the flux linkage observation, i.e. the hybrid flux linkage / torque observer in the embodiment, includes a voltage model (U-I) and a current model (I-ω).

[0083] The mathematical expression of the voltage model (U-I) can be:

[0084]

[0085] wherein, and are rotor fluxes of the motor in the two-phase static coordinate system, L r is a rotor inductance, L s is a stator inductance, and p is a differential operator; specifically, the rotor inductance L r and the stator inductance L s can be obtained according to the stator leakage inductance l ls , the rotor leakage inductance l lr and the mutual inductance L m obtained by the motor in the previous control period.

[0086] The mathematical expression of the current model (I-ω) can be:

[0087]

[0088] wherein, T r is a rotor time constant, and ω r is a rotor angular velocity; specifically, the rotor angular velocity ω r can be obtained according to the rotational speed n.

[0089] The mathematical expression of the mixing rate is:

[0090]

[0091] wherein, γ is the mixing rate, n max is a preset maximum rotational speed of the motor, and n min is a preset minimum rotational speed of the motor.

[0092] When the motor torque T e , the air-gap flux and the rotor flux position of the motor in the current control period are obtained, the flux observation is performed according to the voltage model and / or the current model according to the rotational speed n of the motor. Specifically, the value range of the mixing rate γ is 0-1, when the rotational speed n of the motor is less than n min , the flux observation is performed by the current model (I-ω); when the rotational speed n of the motor is greater than n max , the flux observation is performed by the voltage model (U-I); when the rotational speed n of the motor is between n min and n max , the flux observation is performed by the current model and the voltage model simultaneously.

[0093] The mathematical expression of the air-gap flux linkage is:

[0094]

[0095] wherein, is the air-gap flux linkage of the motor in the two-phase static coordinate system.

[0096] The mathematical expression of the motor torque can be:

[0097]

[0098] wherein, is the rotor flux linkage amplitude, I sq* is the actual torque current of the motor in the two-phase rotating coordinate system.

[0099] In step S108, it is exemplarily illustrated that the stator current amplitude I amp , the motor torque T e and the air-gap flux linkage obtained by the motor in the current control period can be respectively used to look up the stator leakage inductance L ls , the rotor leakage inductance L lr and the excitation mutual inductance L m of the motor in the next control period, so as to obtain the motor torque T e , the air-gap flux linkage and the rotor flux linkage position

[0100] It can be understood that, since the stator leakage inductance L ls , the rotor leakage inductance L lr and the excitation mutual inductance L m are preset values in the first control period of the motor, the motor torque T e , the air-gap flux linkage and the rotor flux linkage position of the motor in the first control period of the motor can be obtained by the preset values.

[0101] In step S109, it is exemplarily illustrated that the I sα , I sβ in the two-phase static coordinate system of the motor can be subjected to the Park transformation according to the rotor flux linkage position , so as to obtain the actual current I sd* , I sq* in the two-phase rotating coordinate system of the motor.

[0102] When the target current of the motor is configured in the full-load state, the current circle, the voltage ellipse, the excitation saturation and the leakage magnetic coefficient can be used as the boundary conditions, for example, the schematic diagram of the working condition division of the target current is as shown in Figure 3As shown, the abscissa represents the target excitation current, and the ordinate represents the target torque current, both in A.

[0103] Therefore, the boundary condition strategy can include a current circle boundary condition, which is mathematically expressed as:

[0104]

[0105] where I sdref is the initial value of the target current, I sqref is the maximum allowable phase current, and I max is the target current.

[0106] Specifically, the target excitation current and the target torque current are limited by the limits of the motor and the inverter, i.e., the maximum allowable phase current I max , and cannot be infinite. Figure 3 In this case, the boundary condition corresponds to a circular portion.

[0107] The boundary condition strategy can also include a voltage ellipse boundary condition, which is mathematically expressed as:

[0108]

[0109] where ω s is the synchronous angular velocity, σ is the leakage coefficient, L s is the stator inductance, and U dc is the bus voltage.

[0110] Specifically, as the motor speed increases, the synchronous angular velocity increases, and the back electromotive force of the motor increases. However, the maximum linear modulation voltage in the space vector modulation is Since the effect of the stator resistance voltage drop can be ignored when the motor speed is high, the target excitation current and the target torque current can be limited by this boundary condition. Figure 3 In this case, the boundary condition corresponds to an elliptical portion; and it can be understood that when the synchronous angular velocity of the motor rises from ω1 to ω2, the voltage ellipse boundary condition converges.

[0111] The boundary condition strategy can also include an excitation saturation boundary condition, which is mathematically expressed as:

[0112] I sdref ≤ I sdrate

[0113] where I sdrate is the rated excitation current.

[0114] Specifically, when the target excitation current does not exceed the rated excitation current I sdrate , the excitation saturation boundary condition is not applicable.When the target excitation current is greater than the rated excitation current I sdrate , increasing the target excitation current can effectively increase the flux linkage and reduce the excitation loss; when the target excitation current exceeds the rated excitation current I sl , increasing the target excitation current will only slightly increase the flux linkage, while the excitation loss will sharply increase, eventually leading to a decrease in motor efficiency, so the target excitation current should also be limited by this boundary condition. Figure 3 In this embodiment, the left part of the straight line where the line segment AB is located corresponds to the boundary condition.

[0115] The boundary condition strategy can also include a leakage coefficient boundary condition, which is mathematically expressed as:

[0116]

[0117] where f sl is the slip frequency of the motor, and T r is the rotor time constant.

[0118] Specifically, when the motor speed is high, it always needs to meet the voltage ellipse boundary condition, the excitation current is continuously reduced, and the slip frequency is continuously increased, and when I sdref = σI sqref , the torque output reaches the extreme value, and the working state of the motor under the target excitation current and the target torque current is optimal. Figure 3 In this embodiment, the lower part of the straight line where the line segment OC is located corresponds to the boundary condition.

[0119] As shown in FIG. 6, the step of configuring the target current of the motor in the dynamic coordinate system can be step S2, which includes: Figure 4

[0120] S201: receiving a target torque sent by a vehicle controller, the target torque being less than the maximum value of the motor torque;

[0121] S202: obtaining an initial value of the target current according to the target torque;

[0122] S203: obtaining the target current of the motor in the dynamic coordinate system according to the initial value of the target current and a preset boundary condition strategy, wherein the target current includes a target excitation current and a target torque current.

[0123] In step S201, it is exemplarily illustrated that the motor receives a target torque T eref sent by the vehicle controller in a full-load state, and the target torque T eref needs to be less than the maximum value of the motor torque, otherwise the motor cannot output according to the target torque.

[0124] In step S202, it is exemplarily illustrated that when the motor is based on rotor field orientation, the mathematical expression of the target torque T eref is:

[0125]

[0126] wherein I sdref is the initial value of the target current, N sqref is the number of motor pole pairs, L p is the motor excitation mutual inductance, L m is the rotor inductance; r

[0127] According to the initial value of the target current, the assumption condition that the target excitation current is equal to the target torque current is proposed, so the initial value of the target current I sdref is obtained. sqref The mathematical expression of I sdref is:

[0128]

[0129] In step S203, it is exemplarily illustrated that according to the initial value of the target current I sdref , I sqref and the preset boundary condition strategy, the target current I sd , I sq of the motor in the two-phase rotating coordinate system is obtained.

[0130] As shown in Figure 4 , the above step S201 receives the target torque sent by the vehicle controller, which previously includes:

[0131] S200: Obtain the maximum allowable phase current I max and the rated excitation current I sdrate of the motor.

[0132] In step S200, it is exemplarily illustrated that the value of the maximum allowable phase current I max depends on the insulation capability and heat dissipation capability of the motor and the inverter, and can be obtained according to the method of electromagnetic simulation test; the rated excitation current I sdrate can be obtained according to the rated parameters of the motor, and the rated parameters include rated voltage, rated current, rated frequency, rated slip frequency and rated speed.

[0133] As shown in Figure 3 , the above step S203 can include a first working condition:

[0134] When the initial value of the target current I sdref and I sqref satisfy the voltage ellipse boundary condition and the excitation saturation boundary condition at the same time, in other words, when the mathematical expression of the boundary condition strategy is:

[0135] and Isdref ≤I sdrate

[0136] When all conditions are met, the target current of the motor in the dynamic coordinate system is equal to the initial value I of the target excitation current. sdref .

[0137] It is understandable that the configured target current is located at Figure 3 On line segment OA in the diagram.

[0138] The above step S203 may also include a second working condition:

[0139] When the initial value of the target current I sdref and I sqref When only the voltage elliptic boundary condition is satisfied, but the excitation saturation boundary condition is not satisfied, in other words, when the mathematical expression of the boundary condition strategy is:

[0140] and I sdref >I sdrate

[0141] When all conditions are met, configure the target excitation current I. sd Equal to the rated excitation current I sdrate And based on the target torque and the target excitation current I sd Obtain the target torque current I sq Meanwhile, the configured target current satisfies the mathematical expression: and In other words, the configured target current satisfies both the current circular boundary condition and the voltage elliptical boundary condition.

[0142] It is understandable that the configured target current is located at Figure 3 On line segment AB in the diagram.

[0143] The above step S203 may also include a third working condition:

[0144] When the initial value of the target current I sdref and I sqref When the voltage elliptic boundary condition is not satisfied, in other words, the mathematical expression of the boundary condition strategy is:

[0145]

[0146] When the target torque is satisfied, the slip frequency is increased step by step based on the original distribution value of the target current, and the solution value I of the target current is obtained according to the target torque and slip frequency. sd_k I sq_k Specifically, to obtain the solution value I of the target current. sd_k I sq_k The mathematical expression is:

[0147]

[0148] wherein f sl1 is the slip frequency corresponding to the original allocation value of the target current, f sl_k is the slip frequency corresponding to the solved value of the target current, and k is 1, 2, 3, ….

[0149] If there exist solved values I sd_k and I sq_k that satisfy the mathematical expression: In other words, if there exist solved values I sd_k and I sq_k that satisfy the voltage ellipse boundary condition, the target current I sd and I sq are configured to be equal to the solved values I sd_k and I sq_k , and the configured target current satisfies the mathematical expression: and In other words, the configured target current satisfies both the current circle boundary condition and the leakage coefficient boundary condition.

[0150] It can be understood that the configured target current is located in the region enclosed by OABC (not including the boundary). Figure 3

[0151] The application specifically divides the working condition of the motor in full-load state under the configuration of the target current into three kinds through the boundary condition strategy composed of the current circle, the voltage ellipse, the excitation saturation, and the leakage coefficient, so that the original allocation value of the target current can be reconfigured under any of the above working conditions, and the target torque current and the target excitation current can be accurately obtained.

[0152] After the above steps of configuring the target current of the motor in the dynamic coordinate system are completed, the target current I sd and I sq of the motor in the dynamic coordinate system are subtracted from the actual current I sd* and I sq* , and then transmitted to a proportional-integral controller for proportional-integral processing, so as to obtain the target modulation voltage U sdref and U sqref of the motor in the two-phase rotating coordinate system. Then, the target modulation voltage U sdref and U sqref of the motor in the two-phase rotating coordinate system are subjected to inverse park transformation according to the rotor flux position to obtain the target modulation voltage U αref ​、U βref .

[0153] After that, the target modulation voltage U αref 、U βref of the motor in the two stationary coordinate systems can be vector-modulated by using a seven-segment space vector modulation strategy to obtain three-phase pulse signals t A 、t B 、t C of the motor; after obtaining the three-phase pulse signals t A 、t B 、t C of the motor, the three-phase pulse signals can be transmitted to an inverter for driving the motor, thereby completing the entire control process of the motor. At the same time, the three-phase pulse signals t A 、t B 、t C are also used for voltage reconstruction of three-phase voltages U A 、U B 、U C of the motor in the next control period.

[0154] The technical features of the above embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above embodiments are described, however, as long as the combinations of the technical features do not exist contradictions, they should be considered as the scope of the present disclosure.

[0155] The above embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the scope of the present application. Therefore, the scope of the patent of the present application should be subject to the appended claims.

Claims

1. A method of configuring current for a motor in a full state, characterized by, Comprising: Receiving a target torque sent by a vehicle controller, the target torque being less than a maximum value of a motor torque; Obtaining an initial value of a target current according to the target torque; Obtaining a target current of the motor in a dynamic coordinate system according to the initial value of the target current and a preset boundary condition strategy, wherein the target current comprises a target excitation current and a target torque current; Receiving a target torque sent by a vehicle controller, previously comprising: acquiring motor parameters, the motor parameters comprising a bus voltage of the motor , a synchronous angular velocity , a leakage coefficient , a stator inductance , a slip frequency and a rotor time constant ; acquiring a maximum allowed phase current of the electric machine and a rated excitation current ; The mathematical expression of the boundary condition strategy is: ； wherein and is an initial value of the target current; when the boundary condition strategy is satisfied, stepping up a slip frequency based on a slip frequency obtained when obtaining a raw allocation value of the target current, and obtaining a solution value of the target current according to the target torque and the slip frequency 、 ; if the solution value of the target current exists , satisfies the mathematical expression: , the target current is configured , the solution value of the target current , , and the configured target current satisfies the mathematical expression: and .

2. The method for configuring the current of the motor in the full state according to claim 1, characterized in that, Receiving a target torque sent by a vehicle controller, previously comprising: obtaining motor parameters, the motor parameters comprising a bus voltage of the motor , a synchronous angular velocity , a leakage coefficient , and a stator inductance ; acquiring a maximum allowed phase current of the electric machine and a rated excitation current ; The mathematical expression of the boundary condition strategy is: and ; wherein and is an initial value of the target current; When the boundary condition strategies are all satisfied, the target current of the motor in the dynamic coordinate system is configured to be equal to the initial value of the target excitation current .

3. The method for configuring the current of the motor in the full state according to claim 1, characterized in that, Receiving a target torque sent by a vehicle controller, previously comprising: obtaining motor parameters, the motor parameters comprising a bus voltage of the motor , a synchronous angular velocity , a leakage coefficient , and a stator inductance ; acquiring a maximum allowed phase current of the electric machine and a rated excitation current ; The mathematical expression of the boundary condition strategy is: and ; wherein and is an initial value of the target current; configuring the target excitation current when the boundary condition strategies are all satisfied is equal to the rated excitation current , and according to the target torque and the target excitation current obtaining the target torque current , and the target current configured at the same time satisfies the mathematical expression: and .

4. The method for configuring the current of the motor in the full state according to claim 1, characterized in that, When obtaining the initial value of the target current according to the target torque, a hypothesis condition that the target excitation current is equal to the target torque current is proposed.

5. The method for configuring the current of the motor in the full state according to claim 4, characterized in that, The mathematical expression for obtaining the initial value of the target current is: ； wherein, , is an initial value of the target current, is a target torque, is a number of motor pole pairs, is a motor excitation mutual inductance, is a rotor inductance.

6. The method for configuring the current of the motor in the full state according to claim 2 or 3, characterized in that, The maximum allowable phase current is obtained according to the method of electromagnetic simulation test.

7. The method for configuring the current of the motor in the full state according to claim 2 or 3, characterized in that, The rated excitation current is obtained according to the rated parameters of the motor, and the rated parameters comprise a rated voltage, a rated current, a rated frequency, a rated slip frequency and a rated speed.

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