Measurement deviation compensation method and system for current sensor module

Abstract

The present application relates to a measurement deviation compensation method and system for a current sensor module configured to measure a current flowing through a three-phase winding in a three-phase electric machine, the on-off of the three-phase winding being controlled by a pulse width modulation module. The measurement deviation compensation method comprises the following steps: acquiring voltage signal values output by a current sensor module corresponding to each phase winding in a three-phase winding during a period in which a pulse width modulation module controls the on-off of the three-phase winding; obtaining a deviation compensation amount based on the voltage signal value corresponding to each phase winding; based on the deviation compensation amount and the voltage signal value corresponding to each phase winding, respectively obtaining a voltage compensation value corresponding to each phase winding; and current compensation values corresponding to the phase windings are obtained based on the voltage compensation values corresponding to the phase windings. According to the invention, after the PWM module works, the current sampling loop deviation generated due to the fact that the PWM module controls the on-off action of the three-phase winding is corrected in real time.

Description

Technical Field

[0001] The present application relates to the field of motors, and in particular, to a measurement deviation compensation method and system for a current sensor module. Background Art

[0002] Motor control systems are often used in vehicles as energy conversion devices between high-voltage batteries and motors, converting the direct current (DC) output by the high-voltage battery into the alternating current (AC) required by the motor.

[0003] In order to accurately control the motor, the motor control system often needs to measure the current value of each phase of the motor's stator winding in real time. However, in the actual measurement process, there is often a certain deviation between the current measurement value sampled by the current sensor and the actual value. This deviation will have a more serious impact on the motor, for example, causing abnormal noise, vibration and harshness (NVH), torque fluctuations, low-frequency jitter, additional power loss, etc. Summary of the invention

[0004] The embodiments of the present application provide a measurement deviation compensation method and system for a current sensor module, which are used to correct the current sampling loop deviation generated by the PWM module controlling the on-off action of the three-phase winding in real time after the PWM module is working.

[0005] According to one aspect of the present application, a measurement deviation compensation method for a current sensor module is provided, wherein the current sensor module is configured to measure the current flowing through a three-phase winding in a three-phase motor, and the on-off of the three-phase winding is controlled by a pulse width modulation module. The measurement deviation compensation method comprises: performing a voltage signal value acquisition step during the period when the pulse width modulation module controls the on-off of the three-phase winding, so as to obtain the voltage signal value output by the current sensor module corresponding to each phase winding in the three-phase winding; performing a deviation compensation amount determination step based on the voltage signal value corresponding to each phase winding, so as to obtain the deviation compensation amount; performing a voltage compensation value determination step based on the deviation compensation amount and the voltage signal value corresponding to each phase winding, so as to obtain the voltage compensation value corresponding to each phase winding respectively; and performing a current compensation value determination step based on the voltage compensation value corresponding to each phase winding, so as to obtain the current compensation value corresponding to each phase winding respectively.

[0006] In some embodiments of the present application, optionally, the deviation compensation amount includes the sum of a common mode voltage and a bias voltage of the current sensor module.

[0007] In some embodiments of the present application, optionally, the deviation compensation amount determining step includes determining the sum of the common mode voltage and the bias voltage according to the following formula:

[0008] Vcom +V off =(V outU +V outV +V outW ) / 3;

[0009] Where V com represents the common mode voltage, V off represents the bias voltage, V outU represents the U-phase voltage signal value corresponding to the U-phase winding in the three-phase winding, V outV represents the V-phase voltage signal value corresponding to the V-phase winding in the three-phase winding, V outW Indicates the W-phase voltage signal value corresponding to the W-phase winding in the three-phase winding.

[0010] In some embodiments of the present application, optionally, the voltage compensation value determining step includes determining the voltage compensation value corresponding to each phase winding according to the following formula:

[0011] V U =V outU -(V com +V off );

[0012] V V =V outV -(V com +V off );

[0013] V W =V outW -(V com +V off );

[0014] Where V U represents the U-phase voltage compensation value corresponding to the U-phase winding, V V represents the V-phase voltage compensation value corresponding to the V-phase winding, V W represents the W-phase voltage compensation value corresponding to the W-phase winding.

[0015] In some embodiments of the present application, optionally, the deviation compensation amount includes a common mode voltage.

[0016] In some embodiments of the present application, optionally, the measurement deviation compensation method further includes: when the pulse width modulation module does not control the on and off of the three-phase winding, obtaining the voltage bias value output by the current sensor module corresponding to each phase winding.

[0017] In some embodiments of the present application, optionally, the measurement deviation compensation method further includes: performing a voltage correction value determination step based on the voltage signal value corresponding to each phase winding and the voltage bias value to respectively obtain the voltage correction value corresponding to each phase winding.

[0018] In some embodiments of the present application, optionally, the voltage correction value determining step includes obtaining the voltage correction value corresponding to each phase winding according to the following formula:

[0019] V corU =V outU -V offU ;

[0020] V corV =V outV -V offV ;

[0021] V corW =V outW -V offW ;

[0022] Where V corU represents the U-phase voltage correction value corresponding to the U-phase winding in the three-phase winding, V corV represents the V-phase voltage correction value corresponding to the V-phase winding in the three-phase winding, V corW represents the W-phase voltage correction value corresponding to the W-phase winding in the three-phase winding, V outU represents the U-phase voltage signal value corresponding to the U-phase winding, V outV represents the V-phase voltage signal value corresponding to the V-phase winding, V outW represents the W-phase voltage signal value corresponding to the W-phase winding, V offU represents the U-phase voltage bias value corresponding to the U-phase winding, V offV represents the V-phase voltage bias value corresponding to the V-phase winding, V offW represents the W-phase voltage bias value corresponding to the W-phase winding.

[0023] In some embodiments of the present application, optionally, the deviation compensation amount determination step includes determining the common mode voltage according to the following formula:

[0024] V com =(V corU +V corV +V corW ) / 3;

[0025] Where V com represents the common mode voltage.

[0026] In some embodiments of the present application, optionally, the voltage compensation value determining step includes determining the voltage compensation value of each phase winding according to the following formula:

[0027] V U =V corU -V com ;

[0028] V V =V corV -V com ;

[0029] V W =V corW -V com ;

[0030] Where V U represents the U-phase voltage compensation value corresponding to the U-phase winding, V V represents the V-phase voltage compensation value corresponding to the V-phase winding, V W represents the W-phase voltage compensation value corresponding to the W-phase winding.

[0031] In some embodiments of the present application, optionally, the current compensation value determining step includes determining the current compensation value of each phase winding according to the following formula:

[0032] I U =V U / Gain U ;

[0033] I V =V V / Gain V ;

[0034] I W =V W / Gain W ;

[0035] Among them I U represents the U-phase current compensation value corresponding to the U-phase winding, I V represents the V-phase current compensation value corresponding to the V-phase winding, I W Indicates the W-phase current compensation value corresponding to the W-phase winding, Gain U Indicates the U-phase gain coefficient of the current sensor module corresponding to the U-phase winding, Gain V Indicates the V-phase gain coefficient of the current sensor module corresponding to the V-phase winding, Gain W Indicates the W-phase gain coefficient of the current sensor module corresponding to the W-phase winding.

[0036] In some embodiments of the present application, optionally, the magnitude of the common-mode voltage is equal to the amplitude of an interference signal generated to the current sensor module due to the on-off control of the three-phase winding by the pulse width modulation module.

[0037] In some embodiments of the present application, optionally, the voltage signal value acquisition step includes: at time T / 4 or 3T / 4 within the switching cycle T in which the pulse width modulation module controls the on and off of the three-phase winding, acquiring the voltage signal value output by the current sensor module corresponding to each phase winding in the three-phase winding.

[0038] According to another aspect of the present application, a measurement bias compensation system is provided, comprising: a memory configured to store instructions; and a processor configured to execute the instructions so that the measurement bias compensation system performs any one of the measurement bias compensation methods described above.

[0039] According to yet another aspect of the present application, a vehicle is provided, the vehicle comprising any one of the measurement deviation compensation systems described above.

[0040] According to yet another aspect of the present application, a computer-readable storage medium is provided, wherein instructions are stored in the computer-readable storage medium. When the instructions are executed by a processor, the processor executes any one of the measurement deviation compensation methods described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The above and other objects and advantages of the present application will become more fully apparent from the following detailed description in conjunction with the accompanying drawings, wherein the same or similar elements are represented by the same reference numerals.

[0042] Figure 1 A schematic diagram of a three-phase motor control system and its application environment according to an embodiment of the present application is shown;

[0043] Figure 2 A schematic diagram of current sampling interference according to an embodiment of the present application is shown;

[0044] Figure 3 A flow chart of a measurement deviation compensation method for a current sensor module according to an embodiment of the present application is shown;

[0045] Figure 4 A flow chart of a method for compensating for measurement deviation of a current sensor module according to another embodiment of the present application is shown; and

[0046] Figure 5 A schematic diagram of a measurement deviation compensation system for a current sensor module according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0047] For the purpose of brevity and illustration, the principles of the present application are described herein mainly with reference to its exemplary embodiments. However, those skilled in the art will readily recognize that the same principles are equally applicable to all types of measurement deviation compensation methods and systems for current sensor modules, and that these same or similar principles may be implemented therein, without departing from the true spirit and scope of the present application.

[0048] The following will be combined Figure 1 A three-phase motor control system 110 according to an embodiment of the present application will be described.

[0049] Figure 1 FIG. 1 is a schematic diagram of a three-phase motor control system 110 according to an embodiment of the present application. Figure 1 As shown, the three-phase motor control system 110 is connected between the high-voltage battery 130 and the three-phase motor 120, so that the high-voltage battery 130 can provide driving power for the three-phase motor 120 via the three-phase motor control system 110. The three-phase motor 120 includes a stator and a rotor, wherein the stator includes a three-phase winding. The three-phase winding is defined herein as a U-phase winding, a V-phase winding, and a W-phase winding.

[0050] The three-phase motor control system 110 may include a switch tube module 111, a capacitor 112, a microcontroller unit (MCU, also referred to as "MCU module" in this article) 113, a signal conditioning and filtering module 114, and a current sensor module 115. The switch tube module 111 is connected in parallel with the capacitor 112. The switch tube module 111 includes three bridge arms 121, wherein each of the three bridge arms 121 is respectively connected to a corresponding one of the three-phase windings. The connection point of each winding in the three-phase winding at each bridge arm in the three-phase bridge arm divides the corresponding one of the bridge arms into an upper bridge arm and a lower bridge arm. Figure 1 As shown, the corresponding upper bridge arm and lower bridge arm of each bridge arm 121 are respectively composed of insulated gate bipolar transistors (IGBTs) and diodes connected in parallel with each other. By controlling the on-off configuration of each upper bridge arm and lower bridge arm of each bridge arm 121 in the switch tube module 111, the conduction state of each phase winding of the stator in the three-phase motor 120 can be controlled.

[0051] like Figure 1As shown, the MCU module 113 may include a pulse width modulation (PWM) module 135 and an analog / digital converter (ADC) sampling module 136. The PWM module 135 may be configured to control the on / off of each upper bridge arm and lower bridge arm in the switch tube module 111. That is, the PWM module 135 may control the conduction state of each phase winding of the stator in the three-phase motor 120 by controlling the on / off of each upper bridge arm and lower bridge arm of each bridge arm 121 in the switch tube module 111.

[0052] The current sensor module 115 may be configured to measure the current flowing through each phase winding of the stator in the three-phase motor 120. In some embodiments, the current sensor module 115 may include three Hall current sensors, wherein each Hall current sensor is respectively arranged on a connection line associated with each phase winding to respectively measure the current flowing through a corresponding winding. In an embodiment of the present application, the current sensor module 115 may output a voltage signal, wherein the voltage signal output by the current sensor module 115 may be proportional to the current in the measurement circuit.

[0053] The signal conditioning and filtering module 114 is connected to the current sensor module 115, and can be configured to receive the voltage signal output from the current sensor module 115, and amplify and filter the received voltage signal. The signal conditioning and filtering module 114 can also be connected to the ADC sampling module 136 in the MCU module 113, so that the processed voltage signal can be transmitted to the ADC sampling module 136.

[0054] The ADC sampling module 136 may be configured to convert the received analog voltage signal into a digital signal. The ADC sampling module 136 may form a current sampling loop for each phase stator winding of the three-phase motor 120 together with the current sensor module 115 and the signal conditioning and filtering module 114 .

[0055] During the operation of the PWM module 135, the switch tubes of each upper bridge arm and lower bridge arm in the switch tube module 111 will perform switching actions accordingly. The switching action of the switch tube module 111 will cause the voltage and current to have a higher rate of change relative to time (that is, generate higher du / dt and di / dt), thereby generating higher electromagnetic interference. In this case, the voltage signal generated by the current sensor module 115 will be more susceptible to electromagnetic interference due to the limitations of the spatial layout and the higher sensitivity of the current sensor. In addition, the interference coupled to the current sampling loop cannot be effectively filtered and suppressed, so the current sensor module 115 will produce measurement deviations during the operation of the PWM module 135.

[0056] Next, we will combine Figure 2The relationship between the current sampling interference and the control operation of the PWM module 135 according to one embodiment of the present application is described below.

[0057] Figure 2 FIG. 2 shows a schematic diagram of current sampling interference according to an embodiment of the present application. Figure 2 As shown in FIG. 1 , the current sampling interference may be manifested as an electromagnetic interference signal, wherein the electromagnetic interference signal is superimposed on the voltage signal output by the current sensor module 115 through the current sampling loop. The electromagnetic interference signal received by the current sensor module 115 is as follows: Figure 2 The upper half of the coordinate axis is shown, where Figure 2 The "Δ" shown in the upper half of the coordinate axis refers to the amplitude of the electromagnetic interference signal. The electromagnetic interference signal amplitude Δ acts as interference in the current sensor sampling, which can cause abnormal motor current control, such as asymmetric phase currents in three-phase motors.

[0058] During the operation of the PWM module 135, the PWM module 135 controls the switching frequency of the switch module 111. Figure 2 The lower half of the coordinate axis is shown. Figure 2 It can be seen from the upper and lower coordinate axes of that the frequency of the electromagnetic interference signal received by the current sensor module 115 is the same as the frequency of the switch action in the switch tube module 111. Figure 2 In the example shown in the upper coordinate axis of , the electromagnetic interference signal amplitude Δ to which the current sensor module 115 is subjected is positively biased in the first half of the cycle (i.e., 0-T / 2) corresponding to the cycle (hereinafter referred to as "switching cycle T") in which the switch tube module 111 performs a switching action, and is negatively biased in the second half of the cycle (i.e., T-3T / 2). In actual applications, the positive and negative amplitudes of the electromagnetic interference signal are not necessarily symmetrical.

[0059] In order to prevent the sampling point from being affected by the switching action, in some embodiments, the ADC sampling module 136 can perform sampling at the same time in each switching cycle T of the switch tube module 111, that is, a sampling mechanism of single-point sampling is implemented. Figure 2 In the example shown, sampling can be performed at t1, t3, t5, ... (i.e., T / 4), or at t2, t4, ... (i.e., 3T / 4). The sampling value corresponding to the sampling point at T / 4 or 3T / 4 just falls into the fixed high area or fixed low area of ​​the interference signal, where the fixed high value or the fixed low value corresponds to the actual electromagnetic interference signal amplitude Δ.

[0060] Next, we will combine Figure 3 and Figure 4The measurement deviation compensation method 300 for the current sensor module 132 according to an embodiment of the present application is described. In some embodiments, the measurement deviation compensation method 300 can be implemented by a measurement deviation compensation system 500 (see Figure 5 ) to execute.

[0061] In the embodiment of the present application, the deviation after the PWM module 135 operates may include the voltage offset value of the current sensor module 115 for each phase winding of the three-phase motor 120 and the interference signal amplitude Δ.

[0062] For the convenience of description, the voltage signal value of each phase winding of the three-phase motor output by the current sensor module 115 during the operation of the PWM module 135 (hereinafter referred to as "each phase voltage signal value"), wherein the each phase voltage signal value includes: the U phase voltage signal value V corresponding to the U phase winding outU , corresponding to the V-phase voltage signal value V of the V-phase winding outv And the W-phase voltage signal value V corresponding to the W-phase winding outW .

[0063] For the convenience of description, the voltage bias values ​​corresponding to each phase winding (hereinafter referred to as "each phase voltage bias value") are respectively recorded as: the U phase voltage bias value V corresponding to the U phase winding offU , corresponding to the V-phase voltage bias value V of the V-phase winding offV And the W-phase voltage offset value V corresponding to the W-phase winding offW When the current sensor module 115 has the same structural design and sensor chip for the current sensor of the three-phase winding, there is a situation where the voltage bias values ​​of each phase are equal, that is, as expressed by the following formula 1:

[0064] V off =V offU =V offV =V offW (Formula 1).

[0065] For the convenience of description, the interference signal amplitude Δ corresponding to each phase winding (hereinafter referred to as "each phase interference signal amplitude Δ") is recorded as: the U phase voltage bias value V corresponding to the U phase winding offU , corresponding to the V-phase voltage bias value V of the V-phase winding offV And the W-phase voltage offset value V corresponding to the W-phase winding offW When the current sensor module 115 uses the same power supply for the current sensors of the three-phase windings and the impedance between the current sensor output pin and the power supply pin is low, there is a situation where the amplitude Δ of the interference signal of each phase is equal, that is, as expressed by the following formula 2:

[0066]

[0067] The following relationship exists between the voltage signal value of each phase, the voltage offset value of each phase, and the amplitude Δ of the interference signal of each phase of the current sensor module 115:

[0068] V outU =Gain U ×I U +V offU +Δ U (Formula 3);

[0069] V outV =Gain V ×I V +V offV +Δ V (Formula 4);

[0070] V outW =Gain W ×I W +V offW +Δ W (Formula 5);

[0071] Among them, Gain U 、Gain V 、Gain W Refers to the gain coefficient of each phase of the current sensor of the current sensor module 115 for the three-phase winding, I U ,I V ,I W Refers to the actual current value corresponding to each phase winding. When the current sensor module 115 uses the same structural design and the same current sensor chip for the current sensors of the three-phase windings, there is a situation where the gain coefficients of each phase are equal, that is, as expressed by the following formula 6:

[0072]

[0073] The above equations describing the equal gain coefficients of each phase may have some errors due to external factors such as mechanical tolerance and device inconsistency. However, the impact of this error is much lower than the impact of the deviation caused by the interference signal and can be ignored.

[0074] For the convenience of description, the voltage signal value of each phase of the current sensor module 115 after eliminating the voltage offset value of each phase is referred to as the voltage correction value of each phase, wherein the voltage correction value of each phase includes: the U-phase voltage correction value V corresponding to the U-phase winding corU , corresponding to the V-phase voltage correction value V of the V-phase winding corV , and the W-phase voltage correction value V corresponding to the W-phase winding corW Accordingly, combining equations 3 to 5, the following relationship exists:

[0075] V corU =V outU -V offU =Gain U ×I U +Δ U (Formula 7);

[0076] V corV =V outV -V offV =Gain V ×I V +Δ V (Formula 8);

[0077] V corW =V outW -V offW =Gain W ×I W +Δ W (Formula 9);

[0078] In each switching cycle of the PWM module 135, by combining equations 7 and 8, the common-mode voltage V com Satisfies the following equation:

[0079]

[0080] Combining Equation 10 with Equation 2 and Equation 6, we can obtain the following relationship:

[0081]

[0082] In addition, considering that in the three-phase motor 120 that operates normally, the sum of the currents of the motor windings of each phase is zero, that is, as described by the following equation:

[0083] I U +I V +I W =0 (Formula 12).

[0084] Combining equations 11 and 12, we can obtain the following relationship:

[0085]

[0086] Combining equation 13, we can see that the common-mode voltage V com The size of can represent the amplitude of the interference signal generated by the current sensor module 115 due to the on-off control of the three-phase winding by the PWM module 135.

[0087] In addition, for the common-mode voltage V com With the voltage bias value V offThe sum, in combination with Equations 3 to 5 and Equation 10, has the following relational expression:

[0088]

[0089] The measurement deviation compensation method 300 according to an embodiment of the present application can correct the deviation generated by the current sensor module 132 in real time by improving the sampling mechanism of the ADC module 136 after the PWM module 135 operates. As an example, the measurement deviation compensation method 300 uses the ADC module 135 to simultaneously sample the phase voltage signal values output by the current sensor module 115 within one switching period, where the phase voltage signal values are superimposed with interference signals. On this basis, the measurement deviation compensation method 300 subtracts the common-mode voltage V in the current switching period from each of the phase voltage signal values respectively. During the process of subtracting from each phase voltage signal value, the deviation after the PWM module 135 operates is corrected. In the embodiments of the present application, there are two ways of subtraction, including subtracting the phase voltage offset value first and then subtracting the common-mode voltage V com , or subtracting the sum of the phase voltage offset value and the common-mode voltage V at one time. Both ways of subtraction can correct the deviation generated after the PWM module operates. This article describes these two ways of subtraction in combination with com , or subtracting the sum of the phase voltage offset value and the common-mode voltage V com . Both ways of subtraction can correct the deviation generated after the PWM module operates. This article describes these two ways of subtraction in combination with Figure 3 and Figure 4 respectively.

[0090] Figure 3 FIG. shows a flowchart of a measurement deviation compensation method 300 for a current sensor module according to an embodiment of the present application. As shown in Figure 3 , the measurement deviation compensation method 300 includes steps S310 to S370.

[0091] Step S310 is a start step, and the measurement deviation compensation method 300 can start from step S310. In some embodiments, the measurement deviation compensation method 300 can start to execute in response to the normal high and low voltage supply and normal self-check of the three-phase motor control system 110. After step S310, step S320 can be further executed.

[0092] In step S320, obtain the phase voltage offset values corresponding to the three-phase motor windings of the current sensor module 115 (i.e., the U-phase voltage offset value V offU , the V-phase voltage offset value V offV and the W-phase voltage offset value V offW). In some embodiments, the voltage signal value output by the current sensor module 115 can be obtained before the PWM module 135 works, wherein the voltage signal value of each phase output by the current sensor module 115 before the PWM module 135 works is the voltage bias value of each phase. The "before the PWM module 135 works" mentioned herein may refer to any time when the PWM module 135 does not control the on and off of the three-phase winding. After step S320, step S330 may be further performed.

[0093] In step S330, the voltage signal value (ie, the U-phase voltage signal value V ) output by the current sensor module 115 for the three-phase winding of the three-phase motor 120 can be obtained during the operation of the PWM module 135. outU , V phase voltage signal value V outV And the W phase voltage signal value V outW In some embodiments, step S330 may include: during the operation of the PWM module 135, whenever the PWM module 135 starts to execute a switching cycle T, the counter is started to count, and when the 1 / 4 or 3 / 4 moment of the switching cycle T is reached, the U-phase voltage signal value V output by the current sensor module 115 is obtained. outU , V phase voltage signal value V outV And the W phase voltage signal value V outW . Accordingly, the sampling value obtained at the sampling point at time T / 4 or time 3T / 4 just corresponds to the actual electromagnetic interference signal amplitude Δ. Step S330 of the embodiment of the present application takes time T / 4 and time 3T / 4 as examples. In other embodiments, sampling can also be performed at other fixed times of a switching cycle T. In some embodiments, each time the PWM module 135 completes a switching cycle T, the counter is reset to zero. After step S330, step S340 can be further executed.

[0094] In step S340, a voltage correction value determination step may be performed based on the voltage offset values ​​of each phase obtained in step S320 and the voltage signal values ​​of each phase obtained in step S330 to respectively obtain the voltage correction values ​​of each phase (i.e., the U phase voltage correction value V corU , V phase voltage correction value V corV and W phase voltage correction value V corW ). In some embodiments, the voltage correction value of each phase can be obtained according to the following equations 15 to 17:

[0095] V corU =V outU -V offU (Formula 15);

[0096] V corV =VoutV -V offV (Formula 16);

[0097] V corW =V outW -V offW (Formula 17).

[0098] After step S340, step S350 may be further performed.

[0099] In step S350, the deviation compensation amount determination step may be performed based on the phase voltage correction values ​​obtained in step S340 to obtain the deviation compensation amount. In the embodiment of the present application, the deviation compensation amount includes the common mode voltage V com In some embodiments, the common mode voltage V can be determined according to the following equation 18: com :

[0100] V com =(V corU +V corV +V corW ) / 3(Formula 18).

[0101] After step S350, step S360 may be further performed.

[0102] In step S360, the voltage compensation value determination step can be performed based on the deviation compensation amount obtained in step S350 and the voltage signal value of each phase obtained in step S330 to respectively determine the voltage compensation value of each phase. In this paper, the voltage signal value corrected for the interference signal amplitude and the voltage offset value is referred to as the voltage compensation value, wherein the voltage compensation value of each phase may include: the U-phase voltage compensation value V corresponding to the U-phase winding U , corresponding to the V-phase voltage compensation value V of the V-phase winding V , and the W-phase voltage compensation value V corresponding to the W-phase winding W .

[0103] In some embodiments, the voltage compensation value of each phase winding can be determined according to the following equations 19 to 21 respectively:

[0104] V U =V corU -V com (Formula 19);

[0105] V V =V corV -V com (Formula 20);

[0106] V W =V corW -V com (Formula 21).

[0107] After step S360, step S370 may be further performed.

[0108] In step S370, the current compensation value determination step can be performed based on the voltage compensation values ​​of each phase obtained in step S360 to determine the current compensation values ​​of each phase. Through the deviation compensation correction, the signal output value of the current sensor module 132 after the deviation compensation correction can be obtained, so the obtained current compensation value of each phase can be regarded as the actual value of each phase current. In this paper, the current compensation values ​​of each phase are respectively recorded as: the U-phase current compensation value I corresponding to the U-phase winding U , corresponding to the V-phase current compensation value I of the V-phase winding V , and the W-phase current compensation value I corresponding to the W-phase winding W .

[0109] In some embodiments, the current compensation value of each phase winding can be determined according to the following equations 22 to 24 respectively:

[0110] I U =V U / Gain U (Formula 22);

[0111] I V =V V / Gain V (Formula 23);

[0112] I W =V W / Gain W (Formula 24).

[0113] Figure 3 The illustrated measurement deviation compensation method 300 takes a switching cycle T of the PWM module 135 as an example, firstly samples the voltage values ​​of each phase output by the current sensor module 115 before the PWM module 135 works, and assigns the voltage bias values ​​of each phase thereto, and then samples the voltage signal values ​​of each phase at a fixed time (e.g., time T / 4 or time 3T / 4) based on a switching cycle T. Based on the sampling result, firstly, the bias voltage of the current sensor module 115 is eliminated by using the voltage bias values ​​of each phase to obtain the voltage correction values ​​of each phase, and then the electromagnetic interference signal amplitude Δ is further eliminated on the basis of the voltage correction values ​​of each phase to obtain the actual current of each phase after the deviation compensation.

[0114] Figure 4 FIG. 3 is a flow chart of a method 300 for compensating a measurement deviation of a current sensor module according to another embodiment of the present application. Figure 4 As shown, the measurement deviation compensation method 300 includes steps S410 to S450.

[0115] Step S410 is a starting step, and the measurement deviation compensation method 300 may start at step S410. In some embodiments, the measurement deviation compensation method 300 may start to execute in response to the high and low supply voltages and the self-test of the three-phase motor control system 110 being normal. After step S410, step S420 may be further executed.

[0116] In step S420, the voltage signal value (ie, the U-phase voltage signal value V outU , V phase voltage signal value V outV And the W phase voltage signal value V outW In some embodiments, step S420 may include: during the operation of the PWM module 135, whenever the PWM module 135 starts to execute a switching cycle T, the counter is started to count, and when the 1 / 4 or 3 / 4 moment of the switching cycle T is reached, the U-phase voltage signal value V output by the current sensor module 115 is obtained. outU , V phase voltage signal value V outV And the W phase voltage signal value V outW . Accordingly, the sampling value obtained at the sampling point at time T / 4 or time 3T / 4 just corresponds to the actual electromagnetic interference signal amplitude Δ. Step S420 of the embodiment of the present application takes time T / 4 and time 3T / 4 as examples. In other embodiments, sampling can also be performed at other fixed times of a switching cycle T. In some embodiments, each time the PWM module 135 completes a switching cycle T, the counter is reset to zero. After step S420, step S430 can be further executed.

[0117] In step S430, the deviation compensation amount determination step may be performed based on the phase voltage signal values ​​obtained in step S420 to obtain the deviation compensation amount. In the embodiment of the present application, the deviation compensation amount includes the common mode voltage V com The bias voltage V of the current sensor module 115 off In some embodiments, the common mode voltage V can be determined according to the following formula 25: com With bias voltage V off sum:

[0118] V com +V off =(V outU +V outV +V outW ) / 3 (Formula 25).

[0119] After step S430, step S440 may be further performed.

[0120] In step S440, a voltage compensation value determination step may be performed based on the deviation compensation amount obtained in step S430 and the voltage signal value of each phase obtained in step S420 to respectively determine the voltage compensation value of each phase (i.e., the U phase voltage compensation value V U , V phase voltage compensation value V V , and W phase voltage compensation value V W ). In some embodiments, the voltage compensation value of each phase winding can be determined according to the following equations 26 to 28 respectively:

[0121] V U =V outU -(V com +V off ) (Formula 26);

[0122] V V =V outV -(V com +V off ) (Formula 27);

[0123] V W =V outW -(V com +V off ) (Formula 28).

[0124] After step S440, step S450 may be further performed.

[0125] In step S450, a current compensation value determination step may be performed based on the voltage compensation values ​​of each phase acquired in step S440 to respectively determine the current compensation values ​​of each phase (ie, the U-phase current compensation value I U , V phase current compensation value I V , and W phase current compensation value I W ). In some embodiments, the current compensation value of each phase winding can be determined according to equations 22 to 24 described above.

[0126] Figure 4 The measurement deviation compensation system 500 described herein determines the voltage offset value of each phase and the common mode voltage V based directly on the voltage signal value of each phase collected during the operation of the PWM module 135. com Therefore, it is not necessary to collect the voltage bias values ​​of each phase before the PWM module 135 works. Figure 3 The measurement bias compensation system 500 example described, Figure 4 The described measurement deviation compensation system 500 example is simpler to operate, more convenient to calculate, and can more quickly obtain the current compensation value of each phase after the deviation compensation correction. Figure 3The measurement deviation compensation system 500 described above first collects the voltage offset value V of each phase before the PWM module 135 works. off , the influence of the bias voltage of each sensor can be eliminated based on the actual bias voltage of the three sensors corresponding to the three-phase winding of the current sensor module 115, so that the current compensation value of each phase after the deviation compensation can be more accurate.

[0127] Figure 5 FIG. 5 is a schematic diagram of a measurement deviation compensation system 500 for a current sensor module according to an embodiment of the present application.

[0128] like Figure 5 As shown in , the measurement deviation compensation system 500 may include a memory 510 and a processor 520. The memory 510 and the processor 520 may communicate with each other. In some embodiments, the memory 510 may be a non-volatile memory such as a flash memory, a ROM, a hard disk drive, a magnetic disk, an optical disk, etc. In other embodiments, the memory 510 may also be other types of memory. The memory 510 may be configured to store instructions. The processor 520 may be configured to execute the instructions so that the measurement deviation compensation system 500 performs the measurement deviation compensation method 300 according to one or more embodiments of the present application.

[0129] The ADC sampling module 136 often introduces a fixed deviation in the process of real-time sampling of the output signal of the current sensor module 115. The embodiment of the present application can correct the deviation of the three-phase current sensor generated after the PWM module 135 works in real time. In addition, the embodiment of the present application does not bring additional sampling delay when correcting the deviation of the three-phase current sensor in real time, and the measurement deviation compensation method 300 of the embodiment of the present application is simple and easy to implement, and can be implemented without adding additional hardware circuits to the existing motor control system.

[0130] The present application also provides a vehicle, the vehicle comprising any one of the measurement deviation compensation systems 500 of the embodiments of the present application as described above. The vehicle referred to in the present application may be any suitable vehicle having a drive system consisting of at least a battery, a power conversion device, and a drive motor, such as a hybrid vehicle, an electric vehicle, a plug-in hybrid electric vehicle, etc. Among them, a hybrid vehicle is a vehicle having two or more power sources, such as a gasoline-powered and an electric vehicle.

[0131] According to another aspect of the present application, a computer-readable storage medium is provided, in which instructions are stored. When the instructions are executed by a processor, the processor executes any one of the measurement deviation compensation methods 300 described above. The computer-readable medium referred to in the present application includes various types of computer storage media, which can be any available medium that can be accessed by a general or special computer. For example, the computer-readable medium can include RAM, ROM, EPROM, EEPROM, etc. 2 PROM, register, hard disk, removable disk, CD-ROM or other optical disk storage, disk storage or other magnetic storage device, or can be used to carry or store the desired program code unit in the form of instruction or data structure and can be accessed by general or special computer, or general or special processor. As used herein, the disk usually copies data magnetically, while the dish uses laser to optically copy data. The above combination should also be included in the protection scope of computer-readable medium. Exemplary storage medium is coupled to the processor so that the processor can read and write information from / to the storage medium. In an alternative solution, the storage medium can be integrated into the processor. The processor and the storage medium can reside in the ASIC. The ASIC can reside in the user terminal. In an alternative solution, the processor and the storage medium can reside in the user terminal as discrete components.

[0132] The relevant user personal information that may be involved in the various embodiments of this application is strictly in accordance with the requirements of laws and regulations, following the principles of legality, legitimacy and necessity, based on the reasonable purposes of business scenarios, to process the personal information that users actively provide during the use of products / services or generated due to the use of products / services, as well as the personal information obtained with the user's authorization.

[0133] The user personal information processed by the applicant will vary depending on the specific product / service scenario, and shall be based on the specific scenario in which the user uses the product / service, which may involve the user's account information, device information, driving information, vehicle information or other related information. The applicant will treat the user's personal information and its processing with a high degree of diligence.

[0134] The Applicant attaches great importance to the security of user personal information and has adopted reasonable and feasible security protection measures that comply with industry standards to protect user information and prevent personal information from being accessed, disclosed, used, modified, damaged or lost without authorization.

[0135] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Those skilled in the art can think of other feasible changes or substitutions based on the technical scope disclosed in the present application, and such changes or substitutions are all included in the protection scope of the present application. In the absence of conflict, the implementation modes of the present application and the features in the implementation modes can also be combined with each other. The protection scope of the present application shall be subject to the description of the claims.

Claims

1. A method for compensating measurement deviation of a current sensor module, characterized in that, the current sensor module is configured to measure the current flowing through the three-phase windings of a three-phase motor, and the on / off of the three-phase windings is controlled by a pulse width modulation module. The measurement deviation compensation method includes: performing a voltage signal value acquisition step during the control of the on / off of the three-phase windings by the pulse width modulation module to acquire the voltage signal values output by the current sensor module corresponding to each phase winding in the three-phase windings; performing a deviation compensation amount determination step based on the voltage signal values corresponding to each phase winding to acquire a deviation compensation amount; performing a voltage compensation value determination step based on the deviation compensation amount and the voltage signal values corresponding to each phase winding to respectively acquire the voltage compensation values corresponding to each phase winding; and performing a current compensation value determination step based on the voltage compensation values corresponding to each phase winding to respectively acquire the current compensation values corresponding to each phase winding.

2. The measurement deviation compensation method according to claim 1, characterized in that, the deviation compensation amount includes the sum of the common-mode voltage and the offset voltage of the current sensor module.

3. The measurement deviation compensation method according to claim 2, characterized in that, the deviation compensation amount determination step includes determining the sum of the common-mode voltage and the offset voltage according to the following formula: V com +V off =(V outU +V outV +V outW ) / 3; where V com represents the common-mode voltage, V off represents the bias voltage, V outU represents the U-phase voltage signal value corresponding to the U-phase winding in the three-phase winding, V outV represents the V-phase voltage signal value corresponding to the V-phase winding in the three-phase winding, V outW represents the W-phase voltage signal value corresponding to the W-phase winding in the three-phase winding.

4. The measurement deviation compensation method according to claim 3, characterized in that, the voltage compensation value determination step includes respectively determining the voltage compensation values corresponding to each phase winding according to the following formula: V U = V outU -(V com + V off ); V V = V outV - (V com + V off )); V W = V outW -(V com + V off ); where V U represents the U-phase voltage compensation value corresponding to the U-phase winding, V V represents the V-phase voltage compensation value corresponding to the V-phase winding, V W represents the W-phase voltage compensation value corresponding to the W-phase winding.

5. The measurement deviation compensation method according to claim 1, characterized in that, the deviation compensation amount includes the common-mode voltage.

6. The measurement deviation compensation method according to claim 5, characterized in that, the measurement deviation compensation method further includes: when the pulse width modulation module does not control the on / off of the three-phase windings, acquiring the voltage offset values output by the current sensor module corresponding to each phase winding.

7. The measurement deviation compensation method according to claim 6, characterized in that, the measurement deviation compensation method further includes: performing a voltage correction value determination step based on the voltage signal values and the voltage offset values corresponding to each phase winding to respectively acquire the voltage correction values corresponding to each phase winding.

8. The measurement deviation compensation method according to claim 7, characterized in that, the voltage correction value determination step includes acquiring the voltage correction values corresponding to each phase winding according to the following formula: V corU = V outU - V offU ; V corV = V outV - V offV ; V corW = V outW - V offW ; where V corU represents the U-phase voltage correction value corresponding to the U-phase winding in the three-phase winding, V corV represents the V-phase voltage correction value corresponding to the V-phase winding in the three-phase winding, V corW represents the W-phase voltage correction value corresponding to the W-phase winding in the three-phase winding, V outU represents the U-phase voltage signal value corresponding to the U-phase winding, V outV represents the V-phase voltage signal value corresponding to the V-phase winding, V outW represents the W-phase voltage signal value corresponding to the W-phase winding, V offU represents the U-phase voltage bias value corresponding to the U-phase winding, V offV represents the V-phase voltage bias value corresponding to the V-phase winding, V offW represents the W-phase voltage bias value corresponding to the W-phase winding.

9. The measurement deviation compensation method according to claim 8, characterized in that, the deviation compensation amount determination step includes determining the common-mode voltage according to the following formula: V com = (V corU + V corV + V corW ) / 3; Where V com represents the common-mode voltage mentioned above.

10. The measurement deviation compensation method according to claim 9, characterized in that, the voltage compensation value determination step includes respectively determining the voltage compensation values of each phase winding according to the following formula: V U = V corU - V com ; V V = V corV - V com ; V W = V corW - V com ; where V U represents the U-phase voltage compensation value corresponding to the U-phase winding, V V represents the V-phase voltage compensation value corresponding to the V-phase winding, V W represents the W-phase voltage compensation value corresponding to the W-phase winding.

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