Motor control method and device, electronic equipment and storage medium

Abstract

According to the motor control method and device, the electronic equipment and the storage medium provided by the invention, in the process of driving the motor to operate through biphase modulation, the plurality of control parameters in one modulation period are obtained, and the device loss corresponding to the plurality of saturation phase angles in the set saturation phase angle interval is obtained based on the plurality of control parameters; and selecting a target saturation phase angle with the minimum device loss from the plurality of saturation phase angles, and if the current set saturation phase angle is not consistent with the target saturation phase angle, resetting the saturation phase angle as the target saturation phase angle when the voltage phase angle reaches the set phase angle. Therefore, a proper saturation phase angle can be found, so that the device loss generated in double-phase modulation is minimum, and high-efficiency motor driving is realized.

Description

Technical Field

[0001] The present invention relates to the field of motor control technology, and in particular to a motor control method and device, electronic equipment and storage medium. Background Art

[0002] In the recent trend of energy conservation, the three-phase frequency conversion devices used to control various motors are constantly required to improve their efficiency. In the relevant technology, in response to such demands, a two-phase modulation method has emerged, that is, in the output phase of the frequency converter, one of the phases is saturated to reduce device losses and achieve higher efficiency.

[0003] However, in bi-phase modulation, the saturation phase angle at which the device loss is minimized varies with different operating conditions. Therefore, it is necessary to consider how to determine the appropriate saturation phase angle to minimize the device loss. Summary of the invention

[0004] The problem solved by the present invention is: how to determine a suitable saturation phase angle in bi-phase modulation so as to minimize the device loss.

[0005] In order to solve the above problems, the present invention provides a motor control method, the motor control method comprising:

[0006] In the process of driving the motor with two-phase modulation, a plurality of control parameters within a modulation cycle are obtained;

[0007] Based on the multiple control parameters, device losses corresponding to multiple saturation phase angles within a set saturation phase angle interval are obtained;

[0008] Selecting a target saturation phase angle with minimum device loss from the plurality of saturation phase angles;

[0009] If the currently set saturation phase angle is inconsistent with the target saturation phase angle, when the voltage phase angle reaches the set phase angle, the saturation phase angle is reset to the target saturation phase angle.

[0010] Compared with the prior art, the motor control method of the present invention has the following advantages:

[0011] In the process of driving the motor with two-phase modulation, multiple control parameters within a modulation cycle are obtained, and based on the multiple control parameters, the device losses corresponding to multiple saturation phase angles within the set saturation phase angle interval are obtained, and then the target saturation phase angle with the smallest device loss is selected from the multiple saturation phase angles. If the currently set saturation phase angle is inconsistent with the target saturation phase angle, the saturation phase angle is reset to the target saturation phase angle when the voltage phase angle reaches the set phase angle. In this way, a suitable saturation phase angle can be found to minimize the device loss generated in the two-phase modulation and achieve efficient motor drive.

[0012] Optionally, the step of acquiring a plurality of control parameters within a modulation cycle includes:

[0013] In one of the modulation cycles, the motor current corresponding to each time point is obtained, wherein the time point is obtained by dividing the modulation cycle according to a set interval;

[0014] For each of the saturation phase angles within the set saturation phase angle interval, based on the applied voltage waveform corresponding to the saturation phase angle, obtaining the applied voltage corresponding to each of the time points at the saturation phase angle;

[0015] The multiple control parameters include the motor current corresponding to each time point and the applied voltage at each saturation phase angle within one modulation cycle.

[0016] Optionally, the step of obtaining, based on the multiple control parameters, device losses corresponding to multiple saturation phase angles within the saturation phase angle interval includes:

[0017] For each of the saturation phase angles, calculate the ratio of the applied voltage to the DC voltage corresponding to each of the time points under the saturation phase angle to obtain the modulation ratio corresponding to each of the time points under the saturation phase angle;

[0018] According to the modulation ratio corresponding to each time point under the saturation phase angle and the motor current corresponding to each time point, the IGBT conduction loss, IGBT switching loss and diode loss corresponding to the saturation phase angle are obtained;

[0019] The IGBT conduction loss, IGBT switching loss and diode loss corresponding to the saturation phase angle are summed to obtain the device loss corresponding to the saturation phase angle.

[0020] Optionally, the step of obtaining the IGBT conduction loss, IGBT switching loss and diode loss corresponding to the saturation phase angle according to the modulation ratio corresponding to each time point under the saturation phase angle and the motor current corresponding to each time point comprises:

[0021] Obtaining circuit constants, wherein the circuit constants include IGBT saturation voltage, IGBT switch parameters, and diode same-direction voltage;

[0022] Obtaining the IGBT conduction loss corresponding to the saturation phase angle according to the modulation ratio corresponding to each time point under the saturation phase angle, the IGBT saturation voltage, and the motor current corresponding to each time point;

[0023] Obtaining the IGBT switching loss corresponding to the saturation phase angle according to the motor current, the DC voltage and the IGBT switching parameter corresponding to each of the time points;

[0024] According to the modulation ratio corresponding to each time point under the saturation phase angle, the diode same-direction voltage and the motor current corresponding to each time point, the diode loss corresponding to the saturation phase angle is obtained.

[0025] Optionally, the step of obtaining the IGBT conduction loss corresponding to the saturation phase angle according to the modulation ratio corresponding to each time point under the saturation phase angle, the IGBT saturation voltage value and the motor current corresponding to each time point includes:

[0026] For each of the time points, calculate the product of the modulation ratio corresponding to the time point, the IGBT saturation voltage, and the motor current corresponding to the time point to obtain the IGBT conduction loss at the time point;

[0027] The IGBT conduction losses at all time points are summed to obtain the IGBT conduction losses corresponding to the saturation phase angle.

[0028] Optionally, the IGBT switch parameters include IGBT switch rise time, IGBT switch fall time and switch frequency;

[0029] The step of obtaining the IGBT switching loss corresponding to the saturation phase angle according to the motor current, the DC voltage and the IGBT switching parameters corresponding to each time point comprises:

[0030] Sum the IGBT switch rise time and the IGBT switch fall time to obtain a total switch time;

[0031] Calculate the product of the total switching time and the switching frequency to obtain a switching period, where the switching period represents the time required for the IGBT to complete a switching action;

[0032] For each time point, calculating the product of the motor current, the DC voltage and the switching period corresponding to the time point, to obtain the IGBT switching loss at the time point;

[0033] The IGBT switching losses at all time points are summed to obtain the IGBT switching losses corresponding to the saturation phase angle.

[0034] Optionally, the step of obtaining the diode loss corresponding to the saturation phase angle according to the modulation ratio corresponding to each time point under the saturation phase angle, the diode same-direction voltage and the motor current corresponding to each time point includes:

[0035] For each of the time points, according to the modulation ratio corresponding to the time point, obtain the modulation margin corresponding to the time point;

[0036] Calculate the product of the motor current corresponding to the time point, the diode same-direction voltage and the modulation margin to obtain the diode loss at the time point;

[0037] The diode losses at all time points are summed to obtain the diode losses corresponding to the saturation phase angle.

[0038] Optionally, the set phase angle is n is an integer.

[0039] Optionally, the motor control method further includes:

[0040] Determine whether the currently set saturation phase angle is consistent with the target saturation phase angle;

[0041] If they are consistent, the motor continues to be driven to operate according to the currently set saturation phase angle.

[0042] Optionally, the motor control method further includes:

[0043] Determine whether a stop operation instruction is received;

[0044] If the stop operation instruction is received, the motor is controlled to stop running;

[0045] If the stop operation instruction is not received, then after setting the time length, return to execute the step of obtaining multiple control parameter values ​​within a modulation cycle, wherein the set time length is set according to the load change of the motor.

[0046] The present invention also provides a motor control device, the motor control device comprising:

[0047] An acquisition module, used for acquiring a plurality of control parameters within a modulation cycle during operation of the motor driven by the two-phase modulation;

[0048] A determination module, configured to obtain device losses corresponding to a plurality of saturation phase angles within a set saturation phase angle interval based on the plurality of control parameters;

[0049] A selection module, configured to select a target saturation phase angle with the minimum loss of the device from the multiple saturation phase angles;

[0050] The control module is used to reset the saturation phase angle to the target saturation phase angle when the voltage phase angle reaches the set phase angle if the currently set saturation phase angle is inconsistent with the target saturation phase angle.

[0051] The present invention further provides an electronic device, comprising a processor and a memory, wherein the memory is used to store a program, and the processor is used to implement the above-mentioned motor control method when executing the program.

[0052] The present invention also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the above-mentioned motor control method is implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 A schematic structural diagram of a motor control system provided by the present invention.

[0054] Figure 2 A schematic diagram of a voltage space vector diagram provided by the present invention.

[0055] Figure 3 A schematic diagram of a motor control method provided by the present invention Figure 1 .

[0056] Figure 4 Schematic diagram of the waveforms of output voltage and PWM pulse under different modulation modes provided by the present invention.

[0057] Figure 5 This is a voltage compensation characteristic diagram for different saturation phase angles provided by the present invention.

[0058] Figure 6 The waveform diagram of the bi-phase modulation with a saturation interval of 60 degrees provided by the present invention is shown as follows Figure 1 .

[0059] Figure 7 The voltage waveform diagram of the bi-phase modulation with a saturation interval of 60 degrees provided by the present invention.

[0060] Figure 8 The waveform diagram of the bi-phase modulation with a saturation interval of 60 degrees provided by the present invention is shown as follows Figure 2 .

[0061] Fig. 9 This is a circuit characteristic diagram provided by the present invention when the saturation phase angle φ=π / 6.

[0062] Fig.10 A schematic diagram of device losses at different saturation phase angles when the current phase angle β is 0 degrees provided by the present invention.

[0063] Fig.11 A schematic diagram of device losses at different saturation phase angles when the current phase angle β is 50 degrees provided by the present invention.

[0064] Fig.12 This is a circuit characteristic diagram provided by the present invention when the saturation phase angle φ=0.

[0065] Fig.13 This is a circuit characteristic diagram provided by the present invention when the saturation phase angle φ=π / 3.

[0066] Fig.14 A schematic diagram of a motor control method provided by the present invention Figure 2 .

[0067] Fig.15 A block diagram of a motor control device provided by the present invention.

[0068] Fig.16 A block diagram of an electronic device provided by the present invention.

[0069] Description of reference numerals:

[0070] 10 - electronic device; 11 - processor; 12 - memory; 13 - bus; 100 - motor control device; 101 - acquisition module; 102 - determination module; 103 - selection module; 104 - control module. DETAILED DESCRIPTION

[0071] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0072] The motor control method provided in an embodiment of the present invention is applied to a processor of an electronic device, which is a device that needs to determine a suitable saturation phase angle to minimize the device loss generated in the two-phase modulation. For example, it can be a household appliance such as an air conditioner and a washing machine, or it can be a car, a generator, etc. The following embodiment is described using an air conditioner as an example. The air conditioner can be an air conditioner using a heat pump system, for example, an air source heat pump air conditioning system, etc.

[0073] In order to make the technical solution to be introduced below easier to understand, before introducing the motor control method provided by the embodiment of the present invention, a motor control system applied to an electronic device is first introduced.

[0074] like Figure 1 As shown, the motor control system includes a frequency converter and a processor. The frequency converter is electrically connected between the AC power supply and the motor, and is used to receive input from the AC power supply and convert it into a voltage and frequency suitable for the motor.

[0075] The inverter is electrically connected to the processor, which runs control algorithms that determine the required PWM signals based on the motor's operating status and performance requirements. Based on the PWM signals output by the controller, the switching elements (such as IGBTs or transistors) in the inverter will switch in a specific pattern to adjust the voltage and frequency output to the motor.

[0076] The frequency converter includes: a rectifier circuit, a smoothing capacitor, a frequency conversion circuit and a shunt resistor. The AC power output by the AC power source is converted into DC power through the rectifier circuit and the smoothing capacitor, and is supplied to the frequency conversion circuit. The frequency conversion circuit includes switch devices 4a-9a and diodes 4b-9b connected in parallel with the switch devices 4a-9a. The switch devices 4a-9a can be IGBTs or transistors. The switch devices 4a-9a and the diodes 4b-9b constitute the upper bridge arm devices and the lower bridge arm devices of the three phases U, V, and W. Each phase has an upper bridge arm device and a lower bridge arm device. The connection point of the upper bridge arm device and the lower bridge arm device is electrically connected to the motor.

[0077] In the frequency conversion circuit of the inverter, seven instantaneous voltage vectors are synthesized by controlling the on and off states of each upper bridge arm device and lower bridge arm device. Each instantaneous voltage vector is encoded with a 3-bit number. For example, S4 = [1,0,0] means that the upper bridge arm device of phase U, the lower bridge arm device of phase V, and the lower bridge arm device of phase W are in the on state, and the lower bridge arm device of phase U, the upper bridge arm device of phase V, and the upper bridge arm device of phase W are in the off state. In other words, the inverter has eight working states and can form seven instantaneous voltage vectors. The instantaneous voltage vectors formed by the two working states S0 = [0,0,0] and S7 = [1,1,1] are the same, both of which are zero vectors. These instantaneous voltage vectors are output by the pulse amplitude corresponding to the command voltage vector to drive the switching device.

[0078] After drawing seven instantaneous voltage vectors on the voltage vector plane, we can form the following Figure 2 The voltage space vector diagram is shown in Figure 1. Among the seven instantaneous voltage vectors, there are six non-zero vectors V1-V6, and the corresponding switching device working states are S1-S6, and their amplitudes are V dc is a DC voltage, and the difference between two adjacent non-zero vectors in space is In addition, a zero vector is also included (not shown in the figure).

[0079] like Figure 2 As shown, the six non-zero vectors form a regular hexagon and divide the voltage vector space into six sectors (sectors I-VI), each sector corresponding to The zero vector is at the origin of the voltage space vector diagram, and the range inside the regular hexagon corresponds to the voltage range that the inverter can output.

[0080] Using space vector modulation, these instantaneous voltage vectors can be used to generate arbitrary voltage vectors. Figure 2 As shown, when there is a voltage vector V in sector I between two adjacent non-zero vectors V1 and V2, t When V tDecompose into two vectors of axes V1 and V2, and set the action times of the two non-zero vectors V1 and V2 and the zero vector to t1, t2, and t0 respectively. Then, t1, t2, and t0 can be calculated by the following formula:

[0081]

[0082] t2=t s ·K s sin(θ)

[0083] t0=t s -(t1+t2)

[0084] Among them, t s is the carrier period, θ is the voltage vector V t The phase angle of K s is the voltage modulation rate, and K s It can be calculated by the following formula:

[0085]

[0086] At this time, |V t | is the voltage vector V t The amplitude, V dc is the amplitude of the DC voltage of the inverter.

[0087] The controller includes: a current detection unit, a 2-phase conversion unit, a rotation position speed estimation unit, a speed control unit, a current control unit, a modulation unit and a PWM signal generation unit. These units use internal timing functions to control the on and off of each upper bridge arm device and lower bridge arm device, so that the output voltage of the frequency conversion circuit can accurately match the speed command of the motor, that is, the output voltage of the frequency conversion circuit is consistent with the voltage condition required by the speed command of the motor.

[0088] When using two-phase modulation, the controller's control logic for the inverter is as follows:

[0089] 1. Current detection unit: detects the three-phase AC current (I U ,I V ,I W ).

[0090] 2. Rotation position speed estimation unit: Based on the three-phase AC current (I U ,I V ,I W ), and estimate the actual speed of the motor.

[0091] 3. 2-phase conversion unit: convert the three-phase AC current (I U ,IV ,I W ), converted into the actual two-phase current value I d ,I q .

[0092] 4. Speed ​​detection unit: First, based on the input speed command and the actual speed measured by the rotation position speed estimation module, the current command I is calculated through proportional integral control * ; Based on the current command I * and the current phase angle β, according to the following formula:

[0093] I d * =I * ×sin(β)

[0094] I q * =I * ×cos(β)

[0095] Calculate and output a 2-axis current command I consisting of the d-axis in the magnetic flux direction and the q-axis perpendicular to it. d * ,I q * .

[0096] The current phase angle β may be set according to the motor load, for example, with the goal of maximizing the driving torque, or with the goal of maximizing the efficiency, etc.

[0097] 5. Current control unit: According to the two-phase current value I output by the two-phase conversion unit d ,I q and the 2-axis current command I output by the speed control unit d * ,I q * , calculate the d-axis voltage V d and q-axis voltage V q .

[0098] 6. The modulation unit adopts a bi-phase modulation method for modulation, including:

[0099] (1) The d-axis voltage V output by the current control unit d and q-axis voltage V q Transform to the α-axis and β-axis, and get the α-axis voltage V α and β-axis voltage V β , the formula is as follows:

[0100] V α =cosθ×V d -sinθ×V q

[0101] V β = sinθ×V d +cosθ×V q

[0102] (2) According to the α-axis voltage V α and β-axis voltage V β , calculate the output voltage vector V t , the formula is as follows:

[0103]

[0104] θ t =tan -1 (V β / V α )

[0105] Among them, |V t | is the magnitude of the output voltage vector, θ t is the phase angle of the output voltage vector.

[0106] (3) Decomposition of the output voltage vector V based on the voltage space vector diagram t , get the output voltage vector V t The corresponding two non-zero vectors and their action time and the action time of the zero vector.

[0107] (4) Adjust the output voltage vector V t The corresponding two non-zero vectors and their action time and the action time of the zero vector are used to saturate one of the three voltage phases of the inverter. For example, within the set saturation interval, the minimum voltage phase is fixed at the minimum voltage or the maximum voltage phase is fixed at the maximum voltage.

[0108] 7. PWM signal generation unit: According to the adjusted output voltage vector V provided by the modulation unit t The corresponding two non-zero vectors and their action time and the action time of the zero vector are used to calculate the PWM duty cycle, and then the corresponding PWM signal is further generated according to the calculated PWM duty cycle. The switching action of each upper bridge arm device and lower bridge arm device in the inverter is controlled by the PWM signal, so that the lower bridge arm device of the minimum voltage phase is continuously turned on in the saturation range or the lower bridge arm device of the maximum voltage phase is continuously turned on in the set saturation range, thereby realizing two-phase modulation.

[0109] Based on the motor control system introduced above, the motor control method provided by the present invention is introduced in detail.

[0110] Please refer to Figure 3 , Figure 3The flowchart of the motor control method provided by the present invention is shown, and the motor control method may include the following steps:

[0111] S101, in the process of driving the motor to run with two-phase modulation, obtaining a plurality of control parameters within a modulation cycle.

[0112] S102, based on multiple control parameters, obtaining device losses corresponding to multiple saturation phase angles within a set saturation phase angle interval.

[0113] S103, selecting a target saturation phase angle with minimum device loss from a plurality of saturation phase angles.

[0114] S106, if the currently set saturation phase angle is inconsistent with the target saturation phase angle, when the voltage phase angle reaches the set phase angle, the saturation phase angle is reset to the target saturation phase angle.

[0115] In this embodiment, the processor of the electronic device controls the operation of the motor by bi-phase modulation. There are multiple bi-phase modulation modes, and different bi-phase modulation modes have different saturation intervals. In practical applications, the user can select the bi-phase modulation mode to be used before controlling the motor, or the processor of the electronic device can automatically determine the bi-phase modulation mode to be used according to hardware conditions, load conditions, etc., and no limitation is made here.

[0116] Alternatively, if Figure 4 As shown in the figure, the saturation interval of the two-phase modulation can be 60 degrees. In the saturation output of the two-phase modulation 60-degree interval, the phase of the minimum phase or the maximum phase in the three phases can be freely set, and the phase starting the saturation output is defined as the saturation phase angle φ, which can be adjusted within the range of 0 to 60 degrees. Figure 5 As shown, when φ=0, according to the order of areas ①→⑥ in (a), according to Figure 6 The waveform shown in the figure is used for voltage compensation; when φ=π / 6, according to the order of area ①→⑥ in (b), Figure 6 The waveform shown in the figure is used for voltage compensation; when φ=π / 3, according to the order of area ①→⑥ in figure (c), Figure 6 The waveform shown in the figure is used for voltage compensation. Therefore, the saturation phase angle needs to be set to the optimal value to improve efficiency.

[0117] For two-phase modulation with a saturation interval of 60 degrees, the processor can control an upper bridge arm switching device or a lower bridge arm switching device in the inverter to continue to conduct within a 60-degree interval based on the two non-zero vectors corresponding to the output voltage vector and their action time and the action time of the zero vector.

[0118] Combined with Figure 2 , assuming the output voltage vector Vt In sector II, and the lower bridge arm device of phase U in sector I is continuously turned on, the voltage V of the three voltage phases in the inverter can be calculated based on the two non-zero vectors V2 and V3 and their action times t2 and t3 and the action time t0 of the zero vector. U 、V V and V W .

[0119] Then, from the voltage V U 、V V and V W Find the minimum voltage (MIN), the middle voltage (MID) and the maximum voltage (MAX) in the equation, and the corresponding phases are the minimum voltage phase, the middle voltage phase and the maximum voltage phase. Figure 7 As shown, sector II corresponds to 60 to 120 degrees. It can be seen from the figure that the minimum voltage phase, the middle voltage phase and the maximum voltage phase are U, V, and W respectively. At this time, the output of the maximum voltage phase W is fixed at the maximum set voltage value to control the upper bridge arm device of the W phase to continue to conduct in sector II.

[0120] Accordingly, if Figure 7 As shown, in sectors III-VI, the same method as above is used to fix the output of the minimum voltage phase in each sector at the minimum voltage value or the output of the maximum voltage phase at the maximum voltage value, so as to control the lower bridge arm device of the minimum voltage phase or the upper bridge arm device of the maximum voltage phase to continue to conduct in the corresponding sector.

[0121] Since the saturation interval is 60 degrees, a saturation interval includes a sector in the voltage space vector diagram. Figure 8 As shown, within one modulation cycle, the U-phase lower bridge arm device, W-phase upper bridge arm device, V-phase lower bridge arm device, U-phase upper bridge arm device, W-phase upper bridge arm device, and V-phase upper bridge arm device of the inverter are controlled to be continuously turned on in sequence every 60 degrees. In this way, the number of switching times can be reduced to 2 / 3, thereby improving efficiency.

[0122] like Fig. 9 As shown, Fig. 9 From top to bottom in the figure, the schematic diagrams of the three-phase motor current, the three-phase applied voltage, the drive signals of the upper and lower bridge arm switch devices of one of the three phases, the IGBT conduction loss, the IGBT switching loss, and the loss of the diode connected in parallel with the IGBT are shown in sequence when the saturation interval is 60 degrees and the saturation phase angle φ=π / 6. It can be seen from the figure that the applied voltage is a low voltage saturation output or a high voltage saturation output in the 60-degree interval. When the low voltage saturation output is output, the IGBT of the lower bridge arm is turned on and output, and when the high voltage saturation output is output, the IGBT of the upper bridge arm is turned on and output.

[0123] The conduction loss of the IGBT is the loss caused by the current flowing through the IGBT, and it occurs when the IGBT is turned on. The switching loss of the IGBT is the loss caused by the turn-on and turn-off actions of the IGBT, and the diode loss is the loss caused by the current flowing through the diode. If the current flowing through the motor flows in the same direction as the IGBT of the upper bridge arm, the conduction loss of the IGBT of the upper bridge arm is generated when the IGBT of the upper bridge arm is turned on, and the current flows through the diode of the lower bridge arm at the time of the turn-off, so the diode of the lower bridge arm generates loss. Conversely, if the current flowing through the motor flows in the same direction as the IGBT of the lower bridge arm, the conduction loss of the IGBT of the lower bridge arm is generated when the IGBT of the lower bridge arm is turned on, and the diode loss of the upper bridge arm is generated at the time of the turn-off. The switching loss of the IGBT is generated at the time when the IGBT is turned on and off, respectively, so the device does not generate switching loss at saturated output. In addition, the various losses generated by the device are proportional to the current flowing through the device, and the loss changes with the difference between the phase in the saturated output and the current phase. From Fig. 9 It can be seen that the device loss is affected by the current. If the saturation phase angle φ is changed, the relative phase of the current phase and the voltage phase will also change, so the loss will also change.

[0124] like Fig.10 , 11 As shown, Fig.10 Schematic diagram of the loss of the upper and lower bridge arms (IGBT+diode) when the saturation phase angle φ is 0, π / 6 (30 degrees), and π / 3 (60 degrees) under the condition that the current phase angle β is 0 degrees. Fig.11 The figure is a schematic diagram of the loss of the upper and lower bridge arms (IGBT + diode) when the saturation phase angle φ is 0, π / 6 (30 degrees), and π / 3 (60 degrees) under the condition that the current phase angle β is 50 degrees. It can be seen from the figure that when the current phase angle β is 0 degrees, the loss is the smallest when the saturation phase angle φ is π / 6, and when the current phase angle β is 50 degrees, the loss is the smallest when the saturation phase angle φ is 0. Therefore, the saturation phase angle when the device loss is the smallest is not fixed, but changes with the operating conditions.

[0125] It should be understood that the smaller the device loss is, the better. Therefore, in bi-phase modulation, it is necessary to determine a suitable saturation phase angle to minimize the device loss.

[0126] Based on this, in the process of driving the motor with two-phase modulation, the embodiment of the present invention obtains multiple control parameters within a modulation cycle, and obtains the device losses corresponding to multiple saturation phase angles within the set saturation phase angle interval based on the multiple control parameters, and then selects the target saturation phase angle with the minimum device loss from the multiple saturation phase angles. If the currently set saturation phase angle is inconsistent with the target saturation phase angle, the saturation phase angle is reset to the target saturation phase angle when the voltage phase angle reaches the set phase angle. In this way, a suitable saturation phase angle can be found to minimize the device loss generated in the two-phase modulation and achieve efficient motor drive.

[0127] In step S101, the process of obtaining multiple control parameters within a modulation period may include:

[0128] In a modulation cycle, the motor current corresponding to each time point is obtained, wherein the time point is obtained by dividing the modulation cycle according to a set interval;

[0129] For each saturation phase angle within the set saturation phase angle interval, based on the applied voltage waveform corresponding to the saturation phase angle, obtain the applied voltage corresponding to each time point under the saturation phase angle;

[0130] The multiple control parameters include the motor current corresponding to each time point and the applied voltage at each saturation phase angle within a modulation cycle.

[0131] That is, first, divide the modulation period according to the set interval to obtain N time points, each time point can be expressed as n=1~N, where N is a positive integer greater than 1. The value of the set interval should be combined with the actual situation. If it is too small, N will be too large, and there is a possibility that the amount of calculation will increase greatly and the chip cannot handle it. If it is too large, N will be too small, and there will be problems of low precision and insufficient accuracy. Therefore, it should be set reasonably. Usually, the set interval can be 15 degrees, and the modulation period is 360 degrees. Dividing 360 degrees at intervals of 15 degrees can obtain N=24 time points.

[0132] Then, during a modulation cycle of the motor operation, the motor current corresponding to each time point is recorded, and the motor current corresponding to each time point n=1 to N can be expressed as I(n).

[0133] Afterwards, obtain the applied voltage corresponding to each time point at each saturation phase angle within the saturation phase angle interval within a modulation cycle. Optionally, the saturation phase angle interval can be set to 0 to π / 3, and the applied voltage corresponding to each time point can be taken for each saturation phase angle within 0 to π / 3, or the applied voltage corresponding to each time point can be taken for the three saturation phase angles of 0, π / 6, and π / 3 within 0 to π / 3, without limitation. The following embodiments are described using the three saturation phase angles of 0, π / 6, and π / 3 as examples, and the driving voltages corresponding to each time point at these three saturation phase angles are expressed as V(1,n), V(2,n), and V(3,n), respectively.

[0134] Please refer to Fig.12 , 9 , 13, Fig.12 , 9 , 13, respectively represent the circuit characteristic diagrams when the saturation phase angle φ=0, π / 6, π / 3. Fig.12 , 9 , 13, the driving voltage corresponding to each time point is taken out in turn, and the driving voltage V(1,n), V(2,n), V(3,n) corresponding to each time point when the saturation phase angle φ=0, π / 6, π / 3 is obtained, and n=1~N.

[0135] In step S102, for each saturation phase angle, based on multiple control parameters, a process of obtaining a device loss corresponding to the saturation phase angle within a set saturation phase angle interval may include:

[0136] S1021, calculating the ratio of the applied voltage and the DC voltage corresponding to each time point under the saturated phase angle, and obtaining the modulation ratio corresponding to each time point under the saturated phase angle.

[0137] S1022, according to the modulation ratio corresponding to each time point under the saturation phase angle and the motor current corresponding to each time point, obtain the IGBT conduction loss, IGBT switching loss and diode loss corresponding to the saturation phase angle.

[0138] S1023, summing up the IGBT conduction loss, IGBT switching loss and diode loss corresponding to the saturation phase angle to obtain the device loss corresponding to the saturation phase angle.

[0139] In this embodiment, the modulation ratio is obtained by calculating the ratio of the applied voltage to the DC voltage. The modulation ratio reflects the degree of change of the applied voltage relative to the DC voltage and can represent the amplitude change of the output voltage. Taking the saturation phase angle φ=0, π / 6, π / 3 as an example, after obtaining the driving voltage V(1,n), V(2,n), V(3,n) corresponding to each time point, the ratio between each applied voltage and the DC voltage is calculated to obtain the modulation ratio D(1,n), D(2,n), D(3,n) corresponding to each time point when the saturation phase angle φ=0, π / 6, π / 3, that is:

[0140] D(m,n)=V(m,n) / V dc

[0141] Where m = 1 to 3, n = 1 to N, V dc is a DC voltage.

[0142] At the same time, from Fig. 9 It can be seen that the IGBT conduction loss, IGBT switching loss and diode loss are related to the applied voltage and motor current. Therefore, the IGBT conduction loss, IGBT switching loss and diode loss at the saturation phase angle φ = 0, π / 6, π / 3 can be calculated based on the applied voltage and motor current, and these losses are summed to obtain the device losses corresponding to the saturation phase angles φ = 0, π / 6, π / 3.

[0143] In some possible implementations, in step S1022, for each saturation phase angle, the process of calculating the IGBT conduction loss, IGBT switching loss, and diode loss corresponding to the saturation phase angle may include:

[0144] S10221, obtaining circuit constants, where the circuit constants include IGBT saturation voltage, IGBT switch parameters, and diode same-direction voltage.

[0145] S10222, according to the modulation ratio corresponding to each time point under the saturation phase angle, the IGBT saturation voltage and the motor current corresponding to each time point, obtain the IGBT conduction loss corresponding to the saturation phase angle.

[0146] S10223, obtaining the IGBT switching loss corresponding to the saturation phase angle according to the motor current, DC voltage and IGBT switching parameters corresponding to each time point.

[0147] S10224, obtaining the diode loss corresponding to the saturation phase angle according to the modulation ratio corresponding to each time point under the saturation phase angle, the diode same-direction voltage and the motor current corresponding to each time point.

[0148] From the above content, it can be seen that the IGBT conduction loss is the loss caused by the current flowing through the IGBT. It is generated at the time when the IGBT is turned on, so it is related to the modulation ratio, IGBT saturation voltage and motor current. The IGBT switching loss is the loss caused by the conduction and shutdown actions of the IGBT, so it is related to the motor current, DC voltage and IGBT switching parameters. The diode loss is the loss caused by the current flowing through the diode, so it is related to the modulation ratio, the diode voltage in the same direction and the motor current.

[0149] In step S10221, the circuit constants may include constants reflecting IGBT characteristics and constants reflecting diode characteristics, wherein the IGBT saturation voltage and IGBT switching parameters reflect the IGBT characteristics, the diode same-direction voltage reflects the diode characteristics, and the IGBT switching parameters may include the IGBT switch rise time, the IGBT switch fall time and the switching frequency.

[0150] Optionally, the IGBT conduction losses at the saturation phase angle φ=0, π / 6, π / 3 are respectively expressed as Pcon(1), Pcon(2), Pcon(3), the IGBT switching losses are respectively expressed as Psw(1), Psw(2), Psw(3), and the diode losses are respectively expressed as Pd(1), Pd(2), Pd(3).

[0151] Optionally, in step S10222, the process of calculating the IGBT conduction loss corresponding to the saturation phase angle may include:

[0152] For each time point, the product of the modulation ratio, the IGBT saturation voltage and the motor current corresponding to the time point is calculated to obtain the IGBT conduction loss at the time point;

[0153] The IGBT conduction loss at all time points is summed to obtain the IGBT conduction loss corresponding to the saturation phase angle.

[0154] Taking a saturation phase angle as an example, since the IGBT conduction loss is related to the modulation ratio, IGBT saturation voltage and motor current, the IGBT conduction loss at each time point under the saturation phase angle can be calculated based on the modulation ratio, IGBT saturation voltage and motor current, and then the IGBT conduction loss at all time points can be summed to obtain the IGBT conduction loss corresponding to the saturation phase angle.

[0155] That is, the IGBT conduction loss corresponding to each saturation phase angle is calculated according to the following formula:

[0156]

[0157] Wherein, m represents the saturation phase angle, for example, m=1~3, representing the saturation phase angle φ=0, π / 6, π / 3 respectively; n represents the time point, n=1~N, N is the total number of time points in a modulation cycle, and N is a positive integer greater than 1; Pcon(m) is the IGBT conduction loss corresponding to the saturation phase angle m, D(m,n) is the modulation ratio corresponding to the nth time point under the saturation phase angle m, Vcesat represents the IGBT saturation voltage, and I(n) is the motor current corresponding to the nth time point.

[0158] In step S10223, the process of calculating the IGBT conduction loss corresponding to the saturation phase angle may include:

[0159] The total switching time is obtained by summing the IGBT switching rise time and the IGBT switching fall time;

[0160] Calculate the product of the total switching time and the switching frequency to get the switching cycle, which represents the time required for the IGBT to complete a switching action;

[0161] For each time point, the product of the motor current, DC voltage and switching period corresponding to the time point is calculated to obtain the IGBT switching loss at the time point;

[0162] The IGBT switching losses at all time points are summed to obtain the IGBT switching losses corresponding to the saturation phase angle.

[0163] Taking a saturation phase angle as an example, since the IGBT switching loss is related to the motor current, DC voltage and IGBT switch parameters, we can first calculate the time required for the IGBT to complete a switching action, that is, the switching cycle. The switching cycle can be obtained by calculating the product of the total switching time and the switching frequency, and the total switching time is the sum of the IGBT switch rise time and the IGBT switch fall time. Then, based on the motor current, DC voltage and switching cycle, calculate the IGBT conduction loss at each time point under the saturation phase angle, and then sum the IGBT conduction loss at all time points to obtain the IGBT conduction loss corresponding to the saturation phase angle.

[0164] That is, the IGBT switching loss corresponding to each saturation phase angle is calculated according to the following formula:

[0165]

[0166] Wherein, Psw(m) represents the IGBT switching loss corresponding to the saturation phase angle m, Tr represents the IGBT switching rise time, Tf represents the IGBT switching fall time, and Fc represents the switching frequency.

[0167] In step S10224, the process of calculating the diode loss corresponding to the saturation phase angle may include:

[0168] For each time point, according to the modulation ratio corresponding to the time point, the modulation margin corresponding to the time point is obtained;

[0169] Calculate the product of the motor current, the diode voltage in the same direction and the modulation margin corresponding to the time point to obtain the diode loss at the time point;

[0170] The diode loss at all time points is summed to obtain the diode loss corresponding to the saturation phase angle.

[0171] Taking a saturation phase angle as an example, since the diode loss is related to the modulation ratio, the diode same-direction voltage and the motor current, and according to the above analysis, if the current flowing through the motor flows in the same direction as the IGBT of the upper bridge arm, the diode of the lower bridge arm will produce losses, and if the current flowing through the motor flows in the same direction as the IGBT of the lower bridge arm, the diode of the upper bridge arm will produce losses, so it is necessary to first subtract the modulation ratio from 1 to get the modulation margin. The modulation margin reflects the proportion of unmodulated. If the modulation ratio is close to 1, it means that the applied voltage is close to the DC voltage, and the modulation margin is close to 0. On the contrary, if the modulation ratio is small, it means that the applied voltage is much lower than the DC voltage, and the modulation ratio margin is large. Then, the diode loss at each time point under the saturation phase angle is calculated based on the motor current, the diode same-direction voltage and the modulation margin, and then the diode losses at all time points are summed to obtain the diode loss corresponding to the saturation phase angle.

[0172] That is, the diode loss corresponding to each saturation phase angle is calculated according to the following formula:

[0173]

[0174] Wherein, VF represents the voltage in the same direction of the diode.

[0175] According to the process of step S102, after the device losses corresponding to multiple saturation phase angles (e.g., φ=0, π / 6, π / 3) within the set saturation phase angle interval (e.g., 0-60 degrees) are obtained, the target saturation phase angle φmin with the minimum device loss is found from the multiple saturation phase angles. After that, the currently set saturation phase angle is compared with the target saturation phase angle φmin. If the two are inconsistent, when the voltage phase angle reaches the set phase angle, the saturation phase angle is reset to the target saturation phase angle φmin.

[0176] Optionally, set the phase angle to n is an integer, that is, when the voltage phase angle is a multiple of π / 6 (i.e., 30 degrees), the saturation phase angle is reset to the target saturation phase angle φmin. The reason why the saturation phase is changed at a time point that is a multiple of π / 6 is that if the saturation phase is changed at any time point within π / 6, the output voltage may be disordered before and after the change time point.

[0177] Please refer again Figure 3 , after step S103 , the motor control method provided by the embodiment of the present invention further includes steps S104 to S105 .

[0178] S104, determining whether the currently set saturation phase angle is consistent with the target saturation phase angle.

[0179] S105: If they are consistent, continue to drive the motor to operate according to the currently set saturation phase angle.

[0180] exist Figure 3 Based on Fig.14 , after steps S105 and S106, the motor control method provided by the embodiment of the present invention further includes steps S107 to S109.

[0181] S107, determining whether a stop operation instruction is received.

[0182] S108, if the stop operation instruction is not received, then after setting the time length, return to step S101, wherein the set time length is set according to the load change of the motor.

[0183] S109: If a stop operation instruction is received, the motor is controlled to stop running.

[0184] Optionally, the value of the set time length can be determined according to the frequency of load changes, for example, 5 seconds.

[0185] In this way, a suitable saturation phase angle can be found to minimize the device loss generated in the two-phase modulation and achieve efficient motor drive.

[0186] In order to execute the corresponding steps in the above embodiment and various possible implementation modes, an implementation method of a motor control device is provided below.

[0187] Please refer to Fig.15 , which is a functional module diagram of the motor control device 100 provided by the present invention. It should be noted that the basic principle and technical effect of the motor control device 100 described in this embodiment are the same as those of the aforementioned method embodiment. For the sake of brief description, the parts not mentioned in this embodiment can refer to the corresponding contents of the aforementioned method embodiment. The motor control device 100 is applied to the processor of the electronic device. Fig.15The motor control device 100 is introduced. The motor control device 100 includes: an acquisition module 101 , a determination module 102 , a selection module 103 and a control module 104 .

[0188] The acquisition module 101 is used to acquire a plurality of control parameters within a modulation cycle during the process of driving the motor with two-phase modulation.

[0189] The determination module 102 is used to obtain device losses corresponding to multiple saturation phase angles within a set saturation phase angle interval based on multiple control parameters.

[0190] The selection module 103 is used to select a target saturation phase angle with the minimum device loss from multiple saturation phase angles.

[0191] The control module 104 is configured to reset the saturation phase angle to the target saturation phase angle when the voltage phase angle reaches the set phase angle if the currently set saturation phase angle is inconsistent with the target saturation phase angle.

[0192] Optionally, the acquisition module 101 is specifically used for:

[0193] In a modulation cycle, the motor current corresponding to each time point is obtained, wherein the time point is obtained by dividing the modulation cycle according to a set interval;

[0194] For each saturation phase angle within the set saturation phase angle interval, based on the applied voltage waveform corresponding to the saturation phase angle, obtain the applied voltage corresponding to each time point under the saturation phase angle;

[0195] The multiple control parameters include the motor current corresponding to each time point and the applied voltage at each saturation phase angle within a modulation cycle.

[0196] Optionally, the determination module 102 is specifically configured to:

[0197] For each saturation phase angle, the ratio of the applied voltage to the DC voltage corresponding to each time point under the saturation phase angle is calculated to obtain the modulation ratio corresponding to each time point under the saturation phase angle;

[0198] According to the modulation ratio corresponding to each time point under the saturation phase angle and the motor current corresponding to each time point, the IGBT conduction loss, IGBT switching loss and diode loss corresponding to the saturation phase angle are obtained;

[0199] The IGBT conduction loss, IGBT switching loss and diode loss corresponding to the saturation phase angle are summed to obtain the device loss corresponding to the saturation phase angle.

[0200] Optionally, the determination module 102 executes a method of obtaining the IGBT conduction loss, IGBT switching loss and diode loss corresponding to the saturation phase angle according to the modulation ratio corresponding to each time point under the saturation phase angle and the motor current corresponding to each time point, including:

[0201] Obtaining circuit constants, wherein the circuit constants include IGBT saturation voltage, IGBT switch parameters, and diode same-direction voltage;

[0202] According to the modulation ratio corresponding to each time point under the saturation phase angle, the IGBT saturation voltage and the motor current corresponding to each time point, the IGBT conduction loss corresponding to the saturation phase angle is obtained;

[0203] According to the motor current, DC voltage and IGBT switch parameters corresponding to each time point, the IGBT switch loss corresponding to the saturation phase angle is obtained;

[0204] According to the modulation ratio corresponding to each time point under the saturation phase angle, the diode same-direction voltage and the motor current corresponding to each time point, the diode loss corresponding to the saturation phase angle is obtained.

[0205] Optionally, the determination module 102 executes a method of obtaining the IGBT conduction loss corresponding to the saturation phase angle according to the modulation ratio corresponding to each time point under the saturation phase angle, the IGBT saturation voltage and the motor current corresponding to each time point, including:

[0206] For each time point, the product of the modulation ratio, the IGBT saturation voltage and the motor current corresponding to the time point is calculated to obtain the IGBT conduction loss at the time point;

[0207] The IGBT conduction loss at all time points is summed to obtain the IGBT conduction loss corresponding to the saturation phase angle.

[0208] Optionally, the IGBT switch parameters include an IGBT switch rise time, an IGBT switch fall time, and a switch frequency; the determination module 102 executes a method of obtaining an IGBT switch loss corresponding to a saturation phase angle according to the motor current, the DC voltage, and the IGBT switch parameters corresponding to each time point, including:

[0209] The total switching time is obtained by summing the IGBT switching rise time and the IGBT switching fall time;

[0210] Calculate the product of the total switching time and the switching frequency to get the switching cycle, which represents the time required for the IGBT to complete a switching action;

[0211] For each time point, the product of the motor current, DC voltage and switching period corresponding to the time point is calculated to obtain the IGBT switching loss at the time point;

[0212] The IGBT switching losses at all time points are summed to obtain the IGBT switching losses corresponding to the saturation phase angle.

[0213] Optionally, the determination module 102 executes a method of obtaining a diode loss corresponding to the saturation phase angle according to the modulation ratio corresponding to each time point under the saturation phase angle, the diode same-direction voltage, and the motor current corresponding to each time point, including:

[0214] For each time point, according to the modulation ratio corresponding to the time point, the modulation margin corresponding to the time point is obtained;

[0215] Calculate the product of the motor current, the diode voltage in the same direction and the modulation margin corresponding to the time point to obtain the diode loss at the time point;

[0216] The diode loss at all time points is summed to obtain the diode loss corresponding to the saturation phase angle.

[0217] Optionally, the control module 104 is further configured to: determine whether the currently set saturation phase angle is consistent with the target saturation phase angle; if they are consistent, continue to drive the motor to operate according to the currently set saturation phase angle.

[0218] Optionally, the control module 104 is also used to: determine whether a stop operation instruction is received; if the stop operation instruction is received, control the motor to stop running; if the stop operation instruction is not received, after a set time length, return to execute the step of obtaining multiple control parameter values ​​within a modulation cycle, wherein the set time length is set according to the load change of the motor.

[0219] Please refer to Fig.16 , Fig.16 The electronic device 10 provided by the present invention is a block diagram. The electronic device includes a processor 11, a memory 12 and a bus 13, and the processor 11 is connected to the memory 12 via the bus 13.

[0220] The memory 12 is used to store programs, for example, Fig.15 The motor control device shown includes at least one software function module that can be stored in the memory 12 in the form of software or firmware. After receiving the execution instruction, the processor 11 executes the program to implement the motor control method disclosed in this embodiment.

[0221] The memory 12 is used to store programs or data. The memory 12 can be, but is not limited to, a random access memory (RAM), a read only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable read-only memory (EEPROM), etc.

[0222] The processor 11 may be an integrated circuit chip with signal processing capability. In the implementation process, each step of the motor control method provided in this embodiment can be completed by an integrated logic circuit of hardware in the processor 11 or an instruction in the form of software. The above-mentioned processor 11 may be a general-purpose processor, including a central processing unit (CPU), a microcontroller unit (MCU), a complex programmable logic device (CPLD), a field programmable gate array (FPGA), an embedded ARM and other chips.

[0223] It should be understood that Fig.16 The structure shown is only a schematic diagram of the structure of the electronic device 10. The electronic device 10 may also include Fig.16 More or fewer components as shown, or with Fig.16 Different configurations are shown. Fig.16 Each component shown in the figure can be implemented by hardware, software or a combination thereof.

[0224] The present invention further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by the processor 11, the motor control method disclosed in this embodiment is implemented.

[0225] In summary, the motor control method and device, electronic device and storage medium provided by the present invention, in the process of driving the motor with two-phase modulation, obtain multiple control parameters within a modulation cycle, and obtain the device losses corresponding to multiple saturation phase angles within the set saturation phase angle interval based on the multiple control parameters, and then select the target saturation phase angle with the minimum device loss from the multiple saturation phase angles. If the currently set saturation phase angle is inconsistent with the target saturation phase angle, the saturation phase angle is reset to the target saturation phase angle when the voltage phase angle reaches the set phase angle. In this way, a suitable saturation phase angle can be found to minimize the device loss generated in the two-phase modulation and achieve efficient motor drive.

[0226] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A motor control method, characterized in that: The motor control method comprises: In the process of driving the motor with two-phase modulation, a plurality of control parameters within a modulation cycle are obtained; based on the plurality of control parameters, device losses corresponding to a plurality of saturation phase angles within a set saturation phase angle interval are obtained; Selecting a target saturation phase angle with minimum device loss from the plurality of saturation phase angles; If the currently set saturation phase angle is inconsistent with the target saturation phase angle, when the voltage phase angle reaches the set phase angle, the saturation phase angle is reset to the target saturation phase angle.

2. The motor control method according to claim 1, characterized in that: The step of obtaining a plurality of control parameters within a modulation cycle includes: In one of the modulation cycles, the motor current corresponding to each time point is obtained, wherein the time point is obtained by dividing the modulation cycle according to a set interval; For each of the saturation phase angles within the set saturation phase angle interval, based on the applied voltage waveform corresponding to the saturation phase angle, obtaining the applied voltage corresponding to each of the time points at the saturation phase angle; The multiple control parameters include the motor current corresponding to each time point and the applied voltage at each saturation phase angle within one modulation cycle.

3. The motor control method according to claim 2, characterized in that: The step of obtaining, based on the multiple control parameters, device losses corresponding to multiple saturation phase angles within the saturation phase angle interval includes: For each of the saturation phase angles, calculate the ratio of the applied voltage to the DC voltage corresponding to each of the time points under the saturation phase angle to obtain the modulation ratio corresponding to each of the time points under the saturation phase angle; According to the modulation ratio corresponding to each time point under the saturation phase angle and the motor current corresponding to each time point, the IGBT conduction loss, IGBT switching loss and diode loss corresponding to the saturation phase angle are obtained; The IGBT conduction loss, IGBT switching loss and diode loss corresponding to the saturation phase angle are summed to obtain the device loss corresponding to the saturation phase angle.

4. The motor control method according to claim 3, characterized in that: The step of obtaining the IGBT conduction loss, IGBT switching loss and diode loss corresponding to the saturation phase angle according to the modulation ratio corresponding to each time point under the saturation phase angle and the motor current corresponding to each time point comprises: Obtaining circuit constants, wherein the circuit constants include IGBT saturation voltage, IGBT switch parameters, and diode same-direction voltage; Obtaining the IGBT conduction loss corresponding to the saturation phase angle according to the modulation ratio corresponding to each time point under the saturation phase angle, the IGBT saturation voltage, and the motor current corresponding to each time point; Obtaining the IGBT switching loss corresponding to the saturation phase angle according to the motor current, the DC voltage and the IGBT switching parameter corresponding to each of the time points; According to the modulation ratio corresponding to each time point under the saturation phase angle, the diode same-direction voltage and the motor current corresponding to each time point, the diode loss corresponding to the saturation phase angle is obtained.

5. The motor control method according to claim 4, characterized in that: The step of obtaining the IGBT conduction loss corresponding to the saturation phase angle according to the modulation ratio corresponding to each time point under the saturation phase angle, the IGBT saturation voltage value and the motor current corresponding to each time point comprises: for each time point, calculating the product of the modulation ratio corresponding to the time point, the IGBT saturation voltage and the motor current corresponding to the time point to obtain the IGBT conduction loss at the time point; and summing the IGBT conduction losses at all time points to obtain the IGBT conduction loss corresponding to the saturation phase angle.

6. The motor control method according to claim 4, characterized in that: The IGBT switch parameters include IGBT switch rise time, IGBT switch fall time and switch frequency; The step of obtaining the IGBT switch loss corresponding to the saturation phase angle according to the motor current, the DC voltage and the IGBT switch parameter corresponding to each time point comprises: summing the IGBT switch rise time and the IGBT switch fall time to obtain the total switch time; Calculate the product of the total switching time and the switching frequency to obtain a switching period, where the switching period represents the time required for the IGBT to complete a switching action; For each time point, calculating the product of the motor current, the DC voltage and the switching period corresponding to the time point, to obtain the IGBT switching loss at the time point; The IGBT switching losses at all time points are summed to obtain the IGBT switching losses corresponding to the saturation phase angle.

7. The motor control method according to claim 4, characterized in that: The step of obtaining the diode loss corresponding to the saturation phase angle according to the modulation ratio corresponding to each time point under the saturation phase angle, the diode same-direction voltage and the motor current corresponding to each time point comprises: for each time point, obtaining the modulation margin corresponding to the time point according to the modulation ratio corresponding to the time point; Calculate the product of the motor current corresponding to the time point, the diode same-direction voltage and the modulation margin to obtain the diode loss at the time point; The diode losses at all time points are summed to obtain the diode losses corresponding to the saturation phase angle.

8. The motor control method according to claim 1, characterized in that: The set phase angle is n is an integer.

9. The motor control method according to claim 1, characterized in that: The motor control method further comprises: Determine whether the currently set saturation phase angle is consistent with the target saturation phase angle; If they are consistent, the motor continues to be driven to operate according to the currently set saturation phase angle.

10. The motor control method according to claim 1, characterized in that: The motor control method further comprises: Determine whether a stop operation instruction is received; If the stop operation instruction is received, the motor is controlled to stop running; If the stop operation instruction is not received, then after setting the time length, return to execute the step of obtaining multiple control parameter values ​​within a modulation cycle, wherein the set time length is set according to the load change of the motor.

11. A motor control device, characterized in that: The motor control device comprises: An acquisition module, used for acquiring a plurality of control parameters within a modulation cycle during operation of the motor driven by the two-phase modulation; A determination module, configured to obtain device losses corresponding to a plurality of saturation phase angles within a set saturation phase angle interval based on the plurality of control parameters; A selection module, configured to select a target saturation phase angle with the minimum loss of the device from the multiple saturation phase angles; The control module is used to reset the saturation phase angle to the target saturation phase angle when the voltage phase angle reaches the set phase angle if the currently set saturation phase angle is inconsistent with the target saturation phase angle.

12. An electronic device, characterized in that: The electronic device comprises a processor and a memory, wherein the memory is used to store a program, and the processor is used to implement the motor control method according to any one of claims 1 to 10 when executing the program.

13. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed by a processor, the motor control method according to any one of claims 1 to 10 is implemented.

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