Dead zone compensation control method, electronic equipment, storage medium and product

Abstract

The invention discloses a dead zone compensation control method, electronic equipment, a storage medium and a product, relates to the technical field of motor control, is applied to a motor control system, and comprises the following steps: obtaining an original duty ratio of the motor control system through space vector pulse width modulation, and calculating a compensation duty ratio for dead zone compensation in the motor control system; determining a first partition threshold value according to the minimum pulse width duty ratio of the motor control system, and determining a second partition threshold value according to the minimum pulse width duty ratio and the dead zone duty ratio of the motor control system; according to the first partition threshold value and the second partition threshold value, the duty ratio value interval is divided, and compensation subintervals are obtained; and determining a target compensation subinterval of the original duty ratio in each compensation subinterval, and executing a duty ratio compensation strategy of the target compensation subinterval to obtain a target duty ratio. The technical problem of unstable compensation control is solved.

Description

Technical Field

[0001] The present application relates to the technical field of motor control, and in particular, to a dead-time compensation control method, system, electronic device, storage medium, and computer program product. Background Art

[0002] In existing dead-time compensation control schemes, the duty ratio of dead-time compensation is mainly calculated based on three-phase instantaneous predicted current, and the duty ratio of SVPWM (Space Vector Pulse Width Modulation) modulation is superimposed with the duty ratio of dead-time compensation to drive the motor to operate. However, during overmodulation, limited by the minimum pulse width of the hardware and the dead-time, directly superimposing the dead-time compensation duty ratio easily causes the duty ratio to mutate within adjacent cycles, triggering torque ripple, thereby increasing the total harmonic distortion rate of the current. Therefore, there is a problem of unstable compensation control in the current dead-time compensation control scheme.

[0003] The above content is only used to assist in understanding the technical solution of the present application, and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The main purpose of the present application is to provide a dead-time compensation control method, device, electronic device, storage medium, and computer program product, aiming to solve the technical problem of unstable compensation control.

[0005] To achieve the above object, the present application proposes a dead-time compensation control method applied to a motor control system. The dead-time compensation control method includes:

[0006] A dead-time compensation control method, characterized in that it is applied to a motor control system, and the dead-time compensation control method includes:

[0007] Obtain the original duty ratio of the motor control system through space vector pulse width modulation, and calculate the compensation duty ratio for dead-time compensation in the motor control system;

[0008] Determine a first partition threshold according to the minimum pulse width duty ratio of the motor control system, and determine a second partition threshold according to the minimum pulse width duty ratio and the dead-time duty ratio of the motor control system;

[0009] Divide the duty ratio value range according to the first partition threshold and the second partition threshold to obtain each compensation sub-interval;

[0010] Determine the target compensation sub-interval in which the original duty ratio is located among the compensation sub-intervals, and execute the duty ratio compensation strategy of the target compensation sub-interval to obtain the target duty ratio.

[0011] In one embodiment, the step of calculating the compensation duty ratio for dead-time compensation in the motor control system includes:

[0012] Determine the preset dead time, the turn-on delay, and the turn-off delay of the corresponding power switch tube according to the preset dead-time schedule;

[0013] Determine the conduction voltage drop of the power switch tube and the conduction voltage drop of the diode according to the preset conduction voltage drop loss table, and determine the bus voltage and the switching frequency of the motor control system;

[0014] Obtain the compensation duty ratio for dead-time compensation based on the preset dead time, the turn-on delay, the turn-off delay, the conduction voltage drop of the power switch tube, the conduction voltage drop of the diode, the bus voltage, and the switching frequency.

[0015] The step of obtaining the compensation duty ratio for dead-time compensation based on the preset dead time, the turn-on delay, the turn-off delay, the conduction voltage drop of the power switch tube, the conduction voltage drop of the diode, the bus voltage, and the switching frequency includes:

[0016] Input the preset dead time, the turn-on delay, the turn-off delay, the conduction voltage drop of the power switch tube, the conduction voltage drop of the diode, the bus voltage, and the switching frequency into a preset compensation formula to calculate the compensation duty ratio for dead-time compensation, where the preset compensation formula is:

[0017]

[0018] Duty_dbc is the compensation duty ratio, T d is the preset dead time, T on is the turn-on delay, T off is the turn-off delay, U ce is the conduction voltage drop of the power switch tube, U f is the conduction voltage drop of the diode, U dc is the bus voltage, f pwm is the switching frequency.

[0019] In one embodiment, the step of determining the first partition threshold according to the minimum pulse-width duty ratio of the motor control system and determining the second partition threshold according to the minimum pulse-width duty ratio and the dead-time duty ratio of the motor control system includes:

[0020] Calculate the minimum pulse-width duty ratio and the dead-time duty ratio of the motor control system, where the minimum pulse-width duty ratio is the product of the preset minimum pulse-width time and the switching frequency, and the dead-time duty ratio is the product of the preset dead time and the switching frequency;

[0021] Take the difference between the upper bound of the numerical value in the duty ratio value range and the minimum pulse-width duty ratio as the first partition threshold;

[0022] Take the sum of the minimum pulse width duty ratio and twice the dead time duty ratio as the intermediate value, and take the difference between the upper bound of the numerical value of the duty ratio value range and the intermediate value as the second partition threshold.

[0023] In one embodiment, the duty ratio value range includes an upper bound and a lower bound of the numerical value, the compensation sub-range includes a first compensation sub-range, a second compensation sub-range, a third compensation sub-range, a fourth compensation sub-range, and a fifth compensation sub-range. The steps of dividing the duty ratio value range according to the first partition threshold and the second partition threshold to obtain each compensation sub-range include:

[0024] Denote the range from the first partition threshold to the upper bound of the numerical value as the first compensation sub-range, and denote the range from the first partition threshold to the second partition threshold as the second compensation sub-range;

[0025] Denote the range from the lower bound of the numerical value to the third partition threshold as the third compensation sub-range, and denote the range from the third partition threshold to the fourth partition threshold as the fourth compensation sub-range, where the third partition threshold is the difference between the upper bound of the numerical value and the first partition threshold, and the fourth partition threshold is the difference between the upper bound of the numerical value and the second partition threshold;

[0026] Take the remaining range in the duty ratio value range except the first compensation sub-range, the second compensation sub-range, the third compensation sub-range, and the fourth compensation sub-range as the fifth compensation sub-range.

[0027] In one embodiment, the steps of determining the target compensation sub-range where the original duty ratio is located in each compensation sub-range and performing the duty ratio compensation strategy of the target compensation sub-range to obtain the target duty ratio include:

[0028] When the target compensation sub-range is the first compensation sub-range or the third compensation sub-range, take the original duty ratio as the target duty ratio;

[0029] When the target compensation sub-range is the second compensation sub-range, if the current polarity of the compensation duty ratio is positive, perform a linear attenuation process on the compensation duty ratio, and take the sum of the processed compensation duty ratio and the original duty ratio as the target duty ratio. If the current polarity of the compensation duty ratio is negative, take the sum of the compensation duty ratio and the original duty ratio as the target duty ratio;

[0030] When the target compensation sub - interval is the fourth compensation sub - interval, if the current polarity of the compensation duty cycle is negative, perform a linear attenuation process on the compensation duty cycle, and use the sum of the processed compensation duty cycle and the original duty cycle as the target duty cycle; if the current polarity of the compensation duty cycle is positive, use the sum of the compensation duty cycle and the original duty cycle as the target duty cycle;

[0031] When the target compensation sub - interval is the fifth compensation sub - interval, use the sum of the compensation duty cycle and the original duty cycle as the target duty cycle.

[0032] In one embodiment, after the step of obtaining the target duty cycle by executing the duty - cycle compensation strategy of the target compensation sub - interval, the following steps are further included:

[0033] Judge whether the target duty cycle is within the duty - cycle value range;

[0034] In the case where the target duty cycle is greater than the upper bound value, adjust the target duty cycle to the upper bound value and output it;

[0035] In the case where the target duty cycle is less than the lower bound value, adjust the target duty cycle to the lower bound value and output it.

[0036] In addition, to achieve the above - mentioned purpose, the present application also proposes a dead - zone compensation control system, which is applied to a motor control system. The dead - zone compensation control system includes:

[0037] A calculation module, configured to obtain the original duty cycle of the motor control system through space - vector pulse - width modulation and calculate the compensation duty cycle for dead - zone compensation in the motor control system;

[0038] A determination module, configured to determine a first partition threshold according to the minimum pulse - width duty cycle of the motor control system, and determine a second partition threshold according to the minimum pulse - width duty cycle and the dead - zone duty cycle of the motor control system;

[0039] A partitioning module, configured to partition the duty - cycle value range according to the first partition threshold and the second partition threshold to obtain each compensation sub - interval;

[0040] An adjustment module, configured to determine the target compensation sub - interval in which the original duty cycle is located among the compensation sub - intervals, and execute the duty - cycle compensation strategy of the target compensation sub - interval to obtain the target duty cycle.

[0041] In addition, to achieve the above - mentioned purpose, the present application also proposes an electronic device, which includes: a memory, a processor, and a computer program stored on the memory and executable on the processor. The computer program is configured to implement the steps of the dead - zone compensation control method as described above.

[0042] In addition, to achieve the above object, the present application further provides a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the dead zone compensation control method described above are implemented.

[0043] In addition, to achieve the above object, the present application further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the steps of the dead zone compensation control method described above are implemented.

[0044] The present application provides a dead zone compensation control method, which is applied to a motor control system. The dead zone compensation control method includes: obtaining an original duty ratio of the motor control system through space vector pulse width modulation, and calculating a compensation duty ratio for dead zone compensation in the motor control system; determining a first partition threshold according to the minimum pulse width duty ratio of the motor control system, and determining a second partition threshold according to the minimum pulse width duty ratio and the dead zone duty ratio of the motor control system; dividing the duty ratio value range according to the first partition threshold and the second partition threshold to obtain each compensation sub-interval; determining the target compensation sub-interval where the original duty ratio is located in each compensation sub-interval, and executing the duty ratio compensation strategy of the target compensation sub-interval to obtain the target duty ratio.

[0045] The present application obtains the original duty ratio of the motor through space vector pulse width modulation (SVPWM) technology, and calculates the compensation duty ratio for dead zone compensation according to factors such as system requirements and dead zone time. At the same time, according to the minimum pulse width duty ratio and the dead zone duty ratio of the motor control system, two key thresholds are determined: the first partition threshold and the second partition threshold. Using these two thresholds, the duty ratio range is divided into multiple compensation sub-intervals, and each compensation sub-interval corresponds to a different duty ratio compensation strategy. According to the target compensation sub-interval where the original duty ratio is located, the corresponding duty ratio compensation strategy is selected and executed, and finally the target duty ratio after dead zone compensation is obtained. Compared with the related solutions, when adding the dead zone compensation duty ratio, it is easy to cause the duty ratio to mutate in adjacent cycles, which in turn causes torque ripple. Through the dynamic threshold partitioning and compensation amount attenuation strategy, after determining the target compensation sub-interval, the corresponding duty ratio compensation strategy is executed. Due to the division of the compensation sub-intervals, the compensation granularity is smaller, and the dead zone compensation can be performed more accurately. And applying the duty ratio compensation strategies corresponding to each compensation sub-interval for compensation, considering different compensation situations in different intervals, makes the target duty ratio closer to the ideal duty ratio value, thereby realizing the smooth output of the duty ratio in the whole interval, solving the mutation problem caused by the duty ratio command exceeding the boundary in the traditional dead zone compensation scheme, and solving the systematic instability risk caused by dead zone compensation. Description of the Drawings

[0046] The accompanying drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with this application, and are used together with the specification to explain the principles of this application.

[0047] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the following will briefly introduce the accompanying drawings required for use in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0048] Figure 1 It is a schematic flowchart provided for the first embodiment of the dead zone compensation control method of this application;

[0049] Figure 2 It is a schematic flowchart provided for the second embodiment of the dead zone compensation control method of this application;

[0050] Figure 3 It is a duty cycle jump diagram of the actual output before linearization processing provided by this application;

[0051] Figure 4 It is a duty cycle jump diagram of the actual output after linearization processing provided by this application;

[0052] Figure 5 It is the overall flowchart of the dead zone compensation control method provided by this application;

[0053] Figure 6 It is a schematic module structure diagram of the dead zone compensation control system in the embodiment of this application;

[0054] Figure 7 It is a schematic device structure diagram of the hardware operating environment involved in the dead zone compensation control method in the embodiment of this application.

[0055] The realization of the purpose, functional features, and advantages of this application will be further described with reference to the embodiments and the accompanying drawings. Specific Embodiments

[0056] It should be understood that the specific embodiments described here are only used to explain the technical solutions of this application and are not used to limit this application.

[0057] To better understand the technical solutions of this application, the following will be described in detail in combination with the specification drawings and specific embodiments.

[0058] The embodiments of the present application are applied to a motor control system. The main solution is as follows: obtaining the original duty cycle of the motor control system through space vector pulse width modulation, and calculating the compensation duty cycle for dead-time compensation in the motor control system; determining a first partition threshold according to the minimum pulse width duty cycle of the motor control system, and determining a second partition threshold according to the minimum pulse width duty cycle and the dead-time duty cycle of the motor control system; dividing the duty cycle value range according to the first partition threshold and the second partition threshold to obtain each compensation sub-range; determining the target compensation sub-range in which the original duty cycle is located among the compensation sub-ranges, and executing the duty cycle compensation strategy of the target compensation sub-range to obtain the target duty cycle.

[0059] In this embodiment, for the convenience of description, the dead-time compensation control system is used as the execution subject for the following elaboration.

[0060] Due to the limitations of the hardware minimum pulse width and dead-time in the prior art under over-modulation conditions, directly superimposing the dead-time compensation duty cycle may cause the duty cycle to mutate in adjacent cycles, which will not only directly affect the control performance of the motor, resulting in unstable output torque of the motor and further causing torque ripple, but also cause distortion of the current waveform, thereby increasing the total harmonic distortion rate (THD) of the current. The harmonic distortion has many negative impacts on the motor control system, including increasing the losses of the motor, reducing the efficiency of the motor, causing electromagnetic noise and vibration, etc. Especially in the high-frequency band, the harmonic components may be more significant, posing a serious threat to the stability and reliability of the motor control system.

[0061] The present application provides a solution. Through dynamic threshold partitioning and linear attenuation compensation strategy, combined with hardware constraint conditions (minimum pulse width, dead-time), smooth output of the duty cycle in the full range is achieved, solving the problems of current harmonic distortion and system instability caused by duty cycle mutation, thereby improving the stability of dead-time compensation control.

[0062] It should be noted that the execution subject of this embodiment can be a computing service device with data processing, network communication, and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or an electronic device, a dead-time compensation control system, etc. that can implement the above functions. The following takes the dead-time compensation control system as an example to illustrate this embodiment and the following embodiments.

[0063] Based on this, the embodiments of the present application provide a dead-time compensation control method, which is applied to a motor control system, referring to Figure 1 , Figure 1 is the flowchart of the first embodiment of the dead-time compensation control method of the present application.

[0064] In this embodiment, the dead-time compensation control method includes steps S01 to S04:

[0065] Step S01: Obtain the original duty cycle of the motor control system through space vector pulse width modulation, and calculate the compensation duty cycle for dead-time compensation in the motor control system;

[0066] It should be noted that in the motor control system, the original duty cycle is obtained through space vector pulse width modulation (SVPWM) technology. The motor control system is responsible for controlling and regulating the operating state of the motor, including speed, direction, current, etc. SVPWM is an efficient modulation method that can synthesize three-phase voltage vectors into an equivalent space vector, thereby achieving precise control of the motor current and torque. The original duty cycle is obtained through SVPWM modulation and represents the proportion of the conduction time of the switching device in each inverter switching cycle. It directly determines the amplitude and phase of the motor phase voltage. At the same time, the compensation duty cycle for dead-time compensation needs to be calculated. Since there is an inherent dead-time in the switching process of the switching devices (such as IGBTs) in the inverter, this will cause distortion of the motor phase current during commutation. The purpose of dead-time compensation is to offset this distortion by adjusting the duty cycle. The compensation duty cycle is used to compensate for the error caused by the dead-time in the original duty cycle. The dead-time refers to a time interval set in the power electronic circuit to avoid simultaneous conduction of the two switching devices on the same bridge arm. During this time interval, both switching devices are in the off state, thus preventing short-circuit phenomena caused by simultaneous conduction of the upper and lower tubes and protecting the safety of the circuit and devices. In this solution, the dead-time is a preset fixed value, such as 3 μs.

[0067] It can be understood that in step S01, the original duty cycle (theoretical required value) is output through the SVPWM algorithm, and the compensation duty cycle (dead-time error equivalent value) is calculated based on the three-phase current polarities, providing a basis for subsequent dynamic correction.

[0068] Step S02: Determine the first partition threshold according to the minimum pulse width duty cycle of the motor control system, and determine the second partition threshold according to the minimum pulse width duty cycle and the dead-time duty cycle of the motor control system;

[0069] It should be noted that in order to implement dead-time compensation control more precisely, the first partition threshold and the second partition threshold need to be determined according to the minimum pulse width duty cycle and the dead-time duty cycle of the motor control system. Among them, the minimum pulse width duty cycle is the proportion of the minimum pulse width that the motor control system can recognize. When the duty cycle is less than this value, the system may not be able to accurately control the operating state of the motor. Due to the existence of dead-time, the actual duty cycle will be smaller than the theoretical value by a fixed proportion, and this proportion is the dead-time duty cycle. The first partition threshold is determined by the minimum pulse width duty cycle, and the second partition threshold is calculated based on the minimum pulse width duty cycle and the dead-time duty cycle. The two are used to divide the duty cycle into different compensation sub-intervals.

[0070] It can be understood that in step S02, by determining the partition threshold according to the minimum pulse width duty ratio and dead zone duty ratio of the motor control system, the actual constraints of the dead zone and the minimum pulse width on the duty ratio are quantified, avoiding frequent switching of the compensation logic near the critical value.

[0071] Step S03, according to the first partition threshold and the second partition threshold, divide the duty ratio value range to obtain each compensation sub-range;

[0072] It should be noted that the first partition threshold and the second partition threshold divide the duty ratio value range into different compensation sub-ranges, and each compensation sub-range corresponds to a different compensation strategy to ensure effective dead zone compensation at different duty ratios. The value range of the duty ratio is usually between 0 and 1, which represents the proportion of the high-level time in a cycle. Specifically, a duty ratio of 0 means the signal is always at a low level, while 1 means the signal is always at a high level.

[0073] It can be understood that step S03 divides the duty ratio value range into different compensation sub-ranges, which can achieve fine control of the duty ratio change. Within each compensation sub-range, by adopting the corresponding duty ratio compensation strategy, it can ensure the smooth transition of the duty ratio in adjacent cycles, effectively avoiding the sudden change of the duty ratio in adjacent cycles, thereby reducing the torque ripple and the total harmonic distortion rate of the current.

[0074] Step S04, determine the target compensation sub-range where the original duty ratio is located in each compensation sub-range, and execute the duty ratio compensation strategy of the target compensation sub-range to obtain the target duty ratio.

[0075] It should be noted that after obtaining the original duty ratio and the compensation duty ratio, it is necessary to determine the target compensation sub-range where the original duty ratio is located and execute the corresponding duty ratio compensation strategy to obtain the target duty ratio. The target compensation sub-range is determined according to the position of the original duty ratio, indicating the range where a certain compensation strategy needs to be applied. The duty ratio compensation strategy is determined according to the compensation sub-range and is used to adjust the original duty ratio to compensate for the influence of the dead zone time. The target duty ratio is the duty ratio obtained after dead zone compensation, which is closer to the theoretical value and can reduce the distortion of the motor phase current.

[0076] It can be understood that in step S03, by judging the target compensation sub-range where the original duty ratio is located, the corresponding duty ratio compensation strategy can be accurately selected and executed, realizing more precise dead zone compensation control, ensuring that the duty ratio can meet the actual requirements of the motor after compensation, thereby improving the operation stability and efficiency of the motor.

[0077] In a feasible implementation manner, in step S01, the steps of calculating the compensation duty ratio for dead zone compensation in the motor control system include steps A01 to A03:

[0078] Step A01: Determine the preset dead time, as well as the turn-on delay and turn-off delay of the corresponding power switch tube according to the preset dead-time schedule.

[0079] It should be noted that the preset dead-time schedule is established offline through prior dead-time learning. Under the conditions of a fixed switching frequency and bus voltage, the three-phase current amplitude is controlled to change from 0 to the rated value by the load device, and the set dead time, that is, the preset dead time T d , and the actual turn-on delay T of the power tube is measured on (the time when the switch tube turns on) and the turn-off delay T off (the time when the switch tube turns off), so as to calculate the effective dead time T dtotal :

[0080] T dtotal = T d + T on - T off

[0081] Step A02: Determine the conduction voltage drop of the power switch tube and the conduction voltage drop of the diode according to the preset conduction voltage drop loss table, and determine the bus voltage and switching frequency of the motor control system.

[0082] It should be noted that the preset conduction voltage drop loss table is summarized from the device manual. The device manual records the basic information, electrical characteristics, limit parameters, etc. of the device. By summarizing the device manual, the conduction voltage drop of each device can be obtained, so as to determine the preset conduction voltage drop loss table, which includes the conduction voltage drop of the power switch tube and the conduction voltage drop of the diode. When the electronic device is in the conduction state, the voltage drop across its two ends is called the conduction voltage drop. The conduction voltage drop is an important factor affecting the efficiency of the motor control system. At the same time, the bus voltage and switching frequency of the system are determined synchronously. The bus voltage represents the electric energy output from the power generation station in the power system. After being stepped up by the transformer, it is the voltage collected on the power bus. The switching frequency refers to the frequency at which the switching element (such as a transistor, relay, etc.) in the electronic device or system performs switching operations. It is usually measured in hertz (Hz) and represents the number of switching operations per second.

[0083] Step A03: Obtain the compensation duty cycle for dead-time compensation according to the preset dead time, turn-on delay, turn-off delay, conduction voltage drop of the power switch tube, conduction voltage drop of the diode, bus voltage, and switching frequency.

[0084] It should be noted that the preset dead time, turn-on delay, turn-off delay, conduction voltage drop of the power switch tube, conduction voltage drop of the diode, bus voltage, and switching frequency are input into the preset compensation formula to obtain the compensation duty cycle. Among them, the preset compensation formula is a calculation method designed in advance for calculating the compensation duty cycle for dead-time compensation.

[0085] In this embodiment, through the preset dead-time table, the characteristics of the switching tubes under the current working conditions are matched in real time to ensure that the calculation of the compensation amount is consistent with the physical reality, thereby improving the stability and accuracy of the compensation control. By presetting the conduction voltage drop loss table and combining the bus voltage and switching frequency, comprehensive voltage and loss parameters are provided for the calculation of the compensation duty cycle, which helps to more accurately evaluate the impact of the dead-time effect on the system performance and improve the accuracy of the compensation. On the basis of steps A01 and A02, considering multiple factors such as the preset dead time, turn-on delay, turn-off delay, conduction voltage drop of the power switch tube, conduction voltage drop of the diode, bus voltage, and switching frequency, the compensation duty cycle for dead-time compensation is calculated, improving the accuracy of the compensation and effectively solving the problem of unstable compensation caused by parameter changes in the traditional scheme.

[0086] In a feasible embodiment, in step A03, the steps of obtaining the compensation duty cycle for dead-time compensation according to the preset dead time, turn-on delay, turn-off delay, conduction voltage drop of the power switch tube, conduction voltage drop of the diode, bus voltage, and switching frequency include step A11:

[0087] Step A11: Input the preset dead time, turn-on delay, turn-off delay, conduction voltage drop of the power switch tube, conduction voltage drop of the diode, bus voltage, and switching frequency into the preset compensation formula to calculate the compensation duty cycle for dead-time compensation. Among them, the preset compensation formula is:

[0088]

[0089] Duty_dbc is the compensation duty cycle, T d is the preset dead time, T on is the turn-on delay, T off is the turn-off delay, U ce is the conduction voltage drop of the power switch tube, U f is the conduction voltage drop of the diode, U dc is the bus voltage, f pwm is the switching frequency.

[0090] It should be noted that, as can be seen from step A01, T d +T on -T off is the effective dead time T dtotal , then (T d +T on-T off )*f pwm *U dc is the voltage loss caused by the effective dead time, U ce is the conduction voltage drop of the power switch tube, U f is the conduction voltage drop of the diode, then represents the average loss of the conduction voltage drop of the power device. The sum of the voltage loss caused by the effective dead time and the average loss of the conduction voltage drop of the power device is the voltage for dead time compensation. Since the duty cycle D can be defined as the ratio of the average output voltage U out to the input voltage U in , that is Therefore, the ratio of the voltage for dead time compensation to the bus voltage is the compensation duty cycle for dead time compensation.

[0091] In addition, it should be noted that the compensation duty cycle can also be obtained by predicting the duty cycle change trend of the next cycle through the quadratic polynomial extrapolation method and dynamically adjusting the compensation direction and amplitude. Using the duty cycle change rate (ΔD = D k -D k-1 ), a linear extrapolation prediction model is constructed:

[0092]

[0093] where D k is the duty cycle of the current cycle, D k-1 is the duty cycle of the previous cycle, ΔD is the duty cycle change rate between the current cycle and the previous cycle, is the predicted value of the duty cycle of the next cycle, α is the attenuation factor, α ∈ [0.5, 1], and when it is predicted that will cross the dead time threshold (such as 0.2 or 0.8), the polarity of the compensation duty cycle is adjusted in advance.

[0094] In this embodiment, by inputting multiple key parameters into a preset compensation formula, the compensation duty cycle for dead time compensation is calculated, comprehensively considering the changes in system parameters, improving the accuracy and stability of the compensation. Even when the system parameters change, the stable compensation effect can be maintained by adjusting the compensation duty cycle. At the same time, the quadratic polynomial extrapolation method is introduced to predict the duty cycle change trend of the next cycle, and a linear extrapolation prediction model is constructed using the duty cycle change rate, which can adjust the polarity of the compensation duty cycle in advance to adapt to the changes in system parameters, improving the flexibility and accuracy of the compensation. Especially when the system parameters change greatly, the compensation strategy can be adjusted faster to maintain the stable operation of the system.

[0095] In a feasible implementation manner, in step S02, the steps of determining the first partition threshold according to the minimum pulse width duty ratio of the motor control system and determining the second partition threshold according to the minimum pulse width duty ratio and the dead zone duty ratio of the motor control system include steps A21 to A23:

[0096] Step A21, calculate the minimum pulse width duty ratio and the dead zone duty ratio of the motor control system. Among them, the minimum pulse width duty ratio is the product of the preset minimum pulse width time and the switching frequency, and the dead zone duty ratio is the product of the preset dead zone time and the switching frequency;

[0097] It should be noted that the preset minimum pulse width time refers to the minimum on / off time (such as 2 μs) that the power switch tube drive circuit can stably execute, which is determined by hardware characteristics (such as the response speed of the drive chip and the discharge time of the parasitic capacitance), and can avoid pulse loss or distortion caused by too narrow pulse width to ensure the reliable operation of the switch tube. The preset dead zone time is the switch tube off interval time (such as 3 μs) forcibly inserted to prevent the upper and lower bridge arms from being directly connected, which is configured by the controller software and is used to cover the time difference between the off delay and the on delay of the power tube to prevent short - circuit risks.

[0098] In addition, it should be noted that the calculation formula for the minimum pulse width duty ratio is:

[0099] Duty_MPW = T MPW ·f pwm

[0100] where Duty_MPW is the minimum pulse width duty ratio, T MPW is the preset minimum pulse width time, and f pwm is the switching frequency.

[0101] The calculation formula for the dead zone duty ratio is:

[0102] Duty_Dead = T Dead ·f pwm

[0103] where Duty_Dead is the dead zone duty ratio, T Dead is the preset dead zone time, and f pwm is the switching frequency.

[0104] Step A22, use the difference between the upper bound of the numerical value in the duty ratio value range and the minimum pulse width duty ratio as the first partition threshold;

[0105] Based on the minimum pulse width duty ratio to determine the first partition threshold, the first threshold calculation formula is:

[0106] Duty_X1 = 1 - Duty_MPW

[0107] Among them, Duty_X1 is the first partition threshold, and Duty_MPW is the minimum pulse width duty ratio;

[0108] It should be noted that the upper bound of the value range of the duty ratio is the maximum value in the value range of the duty ratio, that is, the value 1. Correspondingly, the lower bound of the value range of the duty ratio represents the minimum value in the value range of the duty ratio, that is, the value 0. The first partition threshold is the theoretical upper limit of the duty ratio when only considering the minimum pulse width constraint under the condition of positive current. It defines the hardware safety boundary of the duty ratio instruction. By using the first threshold calculation formula, the upper limit of the duty ratio is set to the maximum value allowed by the hardware to ensure that the compensated duty ratio does not exceed the physically achievable range.

[0109] Step A23: Take the sum of the minimum pulse width duty ratio and twice the dead zone duty ratio as the intermediate value, and take the difference between the upper bound of the value range of the duty ratio and the intermediate value as the second partition threshold.

[0110] Based on the minimum pulse width duty ratio and the dead zone duty ratio, the second partition threshold is determined. The second threshold calculation formula is:

[0111] Duty_X2 = 1 - 2 * Duty_Dead - Duty_MPW

[0112] Among them, Duty_X2 is the second partition threshold, and Duty_Dead is the dead zone duty ratio.

[0113] It should be noted that the second partition threshold is the actual available upper limit of the duty ratio when there are double constraints of the minimum pulse width and the dead zone time under the condition of positive current. It defines the transition zone boundary of the duty ratio instruction and is used to dynamically adjust the compensation amount. Through the linear attenuation compensation strategy, it prevents the overshoot of the compensation amount. Among them, due to the symmetry of the voltage loss of the dead zone time in the positive and negative current directions, within a complete PWM cycle (the time experienced from the rising edge of one pulse to the rising edge of the next pulse), the switching actions of the upper and lower tubes each introduce the influence of the dead zone time once, resulting in a total duty ratio loss of twice the single dead zone time. Therefore, double duty ratio compensation (2 * Duty_Dead) is required to cover the bidirectional influence.

[0114] In this embodiment, by defining the first partition threshold, it is possible to block the duty ratio overstep caused by compensation from the source, eliminate the pulse width distortion, ensure that the duty ratio instruction is always within the hardware executable range, avoid pulse loss or misoperation of the drive chip. By defining the second partition threshold, it is possible to linearly attenuate the compensation amount (instead of directly truncating) when approaching the hardware limit, avoid the step jump of the duty ratio, cover the bidirectional dead zone time influence in the positive and negative current directions, improve the compensation accuracy, solve the systematic instability problem caused by the duty ratio mutation in the traditional dead zone compensation, and achieve high-precision and high-reliability motor control.

[0115] Based on the first embodiment of this application, in the second embodiment of this application, the same or similar content as that in the above-mentioned first embodiment can be referred to the above introduction and will not be elaborated hereinafter. On this basis, please refer to Figure 2 , the duty ratio value range includes a numerical upper bound and a numerical lower bound, and the compensation sub-ranges include a first compensation sub-range, a second compensation sub-range, a third compensation sub-range, a fourth compensation sub-range, and a fifth compensation sub-range. In step S03, according to the first partition threshold and the second partition threshold, the steps of dividing the duty ratio value range to obtain each compensation sub-range include steps S11 to S13:

[0116] Step S11, record the range from the first partition threshold to the numerical upper bound as the first compensation sub-range, and record the range from the first partition threshold to the second partition threshold as the second compensation sub-range;

[0117] It should be noted that the first compensation sub-range is the range from Duty_X1 to 1 (numerical upper bound), which represents the critical region. Since it is close to the maximum duty ratio, superimposing dead-time compensation may cause overshoot. The second compensation sub-range is the range from Duty_X1 to Duty_X2, which represents the high-region transition band. In this range, superimposing a positive compensation amount may cause the duty ratio to jump to 1, resulting in torque ripple.

[0118] Step S12, record the range from the numerical lower bound to the third partition threshold as the third compensation sub-range, and record the range from the third partition threshold to the fourth partition threshold as the fourth compensation sub-range, where the third partition threshold is the difference between the numerical upper bound and the first partition threshold, and the fourth partition threshold is the difference between the numerical upper bound and the second partition threshold;

[0119] It should be noted that the third partition threshold is 1 - Duty_X1. Similar to the first partition threshold, it is the theoretical upper limit of the duty ratio when only considering the minimum pulse width constraint in the case of negative current, and it defines the hardware safety boundary of the duty ratio command. The fourth partition threshold is 1 - Duty_X2. Similarly, similar to the second partition threshold, it is the actual available upper limit of the duty ratio when there are double constraints of the minimum pulse width and dead time in the case of negative current.

[0120] In addition, it should be noted that the third compensation sub-range is the range from 1 to 1 - Duty_X1, which is similar to the first compensation sub-range and represents the critical region. Due to symmetry with the first compensation sub-range, the processing method is similar, but considering the influence of negative dead-time compensation. The fourth compensation sub-range is the range from 1 - Duty_X1 to 1 - Duty_X2, which is similar to the second compensation sub-range and represents the low-region transition band. Superimposing a negative compensation amount may cause the duty ratio to jump to 0 (numerical lower bound).

[0121] Step S13: Take the remaining interval in the duty cycle value range except the first compensation sub-interval, the second compensation sub-interval, the third compensation sub-interval, and the fourth compensation sub-interval as the fifth compensation sub-interval.

[0122] It should be noted that the fifth compensation sub-interval is the remaining interval in the total interval except the first compensation sub-interval, the second compensation sub-interval, the third compensation sub-interval, and the fourth compensation sub-interval, that is, the interval from 1 - Duty_X2 to Duty_X2, which represents the middle area. The duty cycle of the middle area is far from the hardware constraint boundary, and the compensation amount will not trigger clamping after being superimposed in this interval.

[0123] In this embodiment, through the dynamic threshold partitioning strategy, the partitioning thresholds Duty_X1 and Duty_X2 are calculated in real time according to the minimum pulse width duty cycle and the dead zone duty cycle, and the duty cycle value range (0 to 1) is finely divided into five compensation sub-intervals. This partitioning method can adopt targeted compensation strategies according to the characteristics of different duty cycle intervals, effectively avoiding problems caused by sudden changes in the duty cycle.

[0124] In a feasible embodiment, in step S04, the steps of determining the target compensation sub-interval where the original duty cycle is located in each compensation sub-interval and performing the duty cycle compensation strategy of the target compensation sub-interval to obtain the target duty cycle include steps B01 - B04:

[0125] Step B01: When the target compensation sub-interval is the first compensation sub-interval or the third compensation sub-interval, take the original duty cycle as the target duty cycle.

[0126] It should be noted that the original duty cycle is denoted as Duty_Svm. When the target compensation sub-interval is the first compensation sub-interval, that is, when the original duty cycle is in the first compensation sub-interval (Duty_Svm > Duty_X1), due to the minimum pulse width reason, compensation is disabled to avoid overboundary jump in the high region. The finally issued target duty cycle (Duty_Final) is: Duty_Final = Duty_Svm; Similarly, when the target compensation sub-interval is the third compensation sub-interval, that is, when the original duty cycle is in the third compensation sub-interval (Duty_Svm < 1 - Duty_X1), due to the minimum pulse width reason, compensation is disabled to avoid overboundary jump in the low region. The finally issued target duty cycle is: Duty_Final = Duty_Svm.

[0127] Step B02: When the target compensation sub-interval is the second compensation sub-interval, if the current polarity of the compensation duty cycle is positive, perform a linear attenuation process on the compensation duty cycle, and take the sum of the processed compensation duty cycle and the original duty cycle as the target duty cycle. If the current polarity of the compensation duty cycle is negative, take the sum of the compensation duty cycle and the original duty cycle as the target duty cycle.

[0128] It should be noted that the current polarity refers to the direction of the motor phase current, which determines the sign of the compensation duty cycle. When the current direction is opposite to the expected direction, the compensation duty cycle should be negative. When the target compensation sub-interval is the second compensation sub-interval, that is, when the original duty cycle is in the second compensation sub-interval, it indicates that it is in the high-region transition zone. If the current polarity of the compensation duty cycle is positive at this time, direct superposition may cause problems such as duty cycle jumps. Therefore, linear attenuation processing is performed on the compensation amount to make it smoothly transition and prevent duty cycle jumps.

[0129] Exemplarily, when Duty_X1 ≥ Duty_Svm > Duty_X2 and Duty_dbc > 0, at this time, the proportion of Duty_Svm in the high-region transition zone is To make the compensation amount smoothly transition, it is necessary to make the compensation amount gradually decrease as the duty cycle approaches the saturation zone until it reaches zero to avoid sudden changes. The compensation weight linearly changes with the position of Duty_Svm in the transition zone (from Duty_X1 to Duty_X2), gradually decaying from 1 (starting point) to 0 (ending point). Therefore, the compensation weight is The finally issued target duty cycle is:

[0130] In addition, it should be noted that when Duty_X1 ≥ Duty_Svm > Duty_X2 and Duty_dbc ≤ 0, since directly superposing the compensation duty cycle will not cause duty cycle jumps, when the current polarity of the compensation duty cycle is negative, the compensation duty cycle can be directly superposed. The finally issued target duty cycle is: Duty_Final = Duty_Svm + Duty_dbc.

[0131] Step B03, when the target compensation sub-interval is the fourth compensation sub-interval, if the current polarity of the compensation duty cycle is negative, perform linear attenuation processing on the compensation duty cycle, and use the sum of the processed compensation duty cycle and the original duty cycle as the target duty cycle. If the current polarity of the compensation duty cycle is positive, use the sum of the compensation duty cycle and the original duty cycle as the target duty cycle;

[0132] It should be noted that when the target compensation sub-interval is the fourth compensation sub-interval, that is, when the original duty cycle is in the fourth compensation sub-interval, it indicates that it is in the low-region transition zone. Similar to the second compensation sub-interval, if the current polarity of the compensation duty cycle is negative at this time, direct superposition may cause problems such as duty cycle jumps. Therefore, linear attenuation processing is performed on the compensation amount to make it smoothly transition and prevent duty cycle jumps.

[0133] Exemplarily, when 1 - Duty_X1 ≤ Duty_Svm < 1 - Duty_X2 and Duty_dbc < 0, since the current is negative at this time, the proportion of Duty_Svm in the low-region transition zone is To prevent jumps in the low-duty ratio region, it is necessary to make the compensation amount gradually decrease as the duty ratio approaches the saturation region. The compensation weight varies linearly with the position of Duty_Svm within the transition region (from 1 - Duty_X1 to 1 - Duty_X2), gradually increasing from 0 (starting point) to 1 (ending point). Therefore, the compensation weight is The finally issued target duty ratio is:

[0134] Exemplarily, to facilitate understanding of the technical concept or principle of this application, please refer to Figure 3 and Figure 4 , Figure 3 A duty ratio jump diagram of the actual output before linearization processing is provided. Figure 4 A duty ratio jump diagram of the actual output after linearization processing is provided. In the field of power electronics, the upper switch usually refers to the switching device connected between the positive pole of the power supply and the load, such as MOSFET or IGBT, etc. The connection between the positive pole and the load is controlled by high-frequency switching; the lower switch is the switching device connected between the load and the negative pole of the power supply, which can also be MOSFET or IGBT, etc. It conducts alternately with the upper switch to realize the switching of the current path. The upper and lower switches need to follow the dead-time rule to prevent direct short circuit and rely on the body diode to handle the freewheeling of inductive loads. In Figure 3 , duty ratio jumps occur within the range of (0.92, 0.95) of the actual duty ratio of the upper switch and within the range of (0.05, 0.08) of 1 - the actual duty ratio of the lower switch. And these two ranges respectively correspond to the high-region transition band and the low-region transition band. Therefore, linear attenuation needs to be performed on the compensated duty ratio. After adjustment, as shown in Figure 4 , where the duty ratio varies uniformly within the range of (0.92, 0.98) of the actual duty ratio of the upper switch and within the range of (0.02, 0.08) of 1 - the actual duty ratio of the lower switch, solving the problem of duty ratio jumps.

[0135] Step B04, when the target compensation sub-interval is the fifth compensation sub-interval, use the sum of the compensated duty ratio and the original duty ratio as the target duty ratio.

[0136] It should be noted that since the fifth compensation sub-interval is far from the hardware constraint boundary, and the dead-time effect is significant and the signal fluctuates frequently in this interval, full compensation is required to eliminate the steady-state error, so as to quickly offset the voltage loss caused by the dead time.

[0137] Exemplarily, when the original duty ratio is within the fifth compensation sub-interval, that is, 1 - Duty_X2 ≤ Duty_Svm < Duty_X2, directly superimpose the compensation to retain the compensation accuracy. The finally issued target duty ratio is: Duty_Final = Duty_Svm + Duty_dbc.

[0138] Additionally, it should be noted that after the dead - zone compensation eliminates the fundamental voltage error, the residual harmonics can be further canceled by harmonic injection. For the 5th and 7th harmonics generated by the dead - zone effect, the 3rd - harmonic voltage V h3 is injected, and its phase is 180° different from the phase of the dead - zone harmonics: V h3 =A h3 ·sin(3ωt + φ dead +π), where V h3 is the injected 3rd - harmonic voltage component used to cancel the inherent low - order harmonics in the inverter output waveform, A h3 is the amplitude of the 3rd - harmonic component, which determines the intensity of harmonic injection. Usually, it takes 20% - 50% of the fundamental voltage amplitude (over - modulation needs to be avoided), 3ωt is the phase angle of the 3rd - harmonic, where ω = 2πf is the fundamental angular frequency (f = 50Hz or 60Hz), and φ dead is the phase shift caused by the dead - zone effect, which is related to the preset dead - zone time T Dead and the polarity of the load current. T s is the PWM switching period, and +π is for inverting the injected harmonics so that their phases are opposite to the phases of the system - inherent harmonics to achieve the cancellation effect. In SVPWM modulation, the dead - zone compensation amount Duty_Dbc is superimposed with the harmonic injection amount Duty_h3. The calculation formula for Duty_h3 is:

[0139]

[0140] where V dc is the bus voltage. The superposition formula for superimposing Duty_Dbc and Duty_h3 is:

[0141] Duty_Final = Duty_Svm+Duty_dbc + k·Duty_h3

[0142] where k represents the adjustment coefficient of the harmonic injection intensity, which controls the trade - off between harmonic cancellation and system stability. k ∈[0.2,0.5], the lower limit is 0.2 to ensure the minimum harmonic suppression effect, and the upper limit is 0.5 to avoid output voltage distortion or excessive stress on the switching devices caused by over - modulation. After superimposing the dead - zone compensation amount and the harmonic injection amount, the dead - zone effect and harmonics can be suppressed simultaneously, reducing the need for additional filter circuits.

[0143] In this embodiment, through dynamic threshold partitioning, the duty cycle is divided into seven compensation sub-intervals, and corresponding compensation strategies are executed according to the characteristics of each interval. In the transition intervals (such as the second compensation sub-interval and the fourth compensation sub-interval), linear attenuation processing is performed according to the current polarity of the compensation duty cycle to ensure a smooth transition of the duty cycle. In the non-transition intervals (such as the first compensation sub-interval, the third compensation sub-interval, and the fifth compensation sub-interval), the compensation duty cycle is directly superimposed or the original duty cycle is kept unchanged to retain the compensation accuracy. This effectively solves the problem of unstable compensation control in the current dead-time compensation control scheme, realizes a smooth output of the duty cycle in the entire interval, and improves the stability and performance of the system.

[0144] In a feasible embodiment, after the step of obtaining the target duty cycle by executing the duty cycle compensation strategy of the target compensation sub-interval in step S03, steps B11 to B13 are further included:

[0145] Step B11, determining whether the target duty cycle is within the duty cycle value range;

[0146] It should be noted that a range check is performed on the calculated target duty cycle to determine whether it is within the valid interval from 0 to 1 (i.e., the duty cycle value range). Since in the actual control process, the duty cycle, as an important parameter of the PWM (pulse width modulation) signal, its value range must be strictly limited between 0 and 1. Values outside this range are physically meaningless, so verification and correction are required.

[0147] Step B12, when the target duty cycle is greater than the upper numerical bound, adjusting the target duty cycle to the upper numerical bound and outputting it;

[0148] It should be noted that if the target duty cycle is greater than 1 (the upper numerical bound), it is corrected to 1 and this corrected value is output. The maximum value of the duty cycle is 1, indicating that the power switch tube is in the on state throughout the entire cycle. If the calculated target duty cycle is greater than 1, it means that there is a calculation error or unreasonable parameter setting. Correcting it to 1 can ensure that the output PWM signal is physically valid and can avoid adverse effects on motor control.

[0149] Step B13, when the target duty cycle is less than the lower numerical bound, adjusting the target duty cycle to the lower numerical bound and outputting it.

[0150] It should be noted that if the target duty cycle is less than 0 (the lower limit of the value), it will be corrected to 0 and the corrected value will be output. The minimum value of the duty cycle is 0, which means that the power switch tube is in the off state during the entire cycle. If the calculated target duty cycle is less than 0, it also means that there is a calculation error or unreasonable parameter setting. Correcting it to 0 can ensure that the output PWM signal is physically valid and avoid adverse effects on motor control.

[0151] In this implementation, through logical judgment, it is verified whether the calculated target duty cycle is within the valid interval [0,1] to ensure that the target duty cycle of subsequent processing is within a reasonable range, providing a prerequisite for subsequent adjustment steps. When it is detected that the target duty cycle exceeds the upper limit (that is, greater than 1), it is automatically adjusted to 1 and the adjusted duty cycle is output to prevent the hardware from being unable to respond correctly due to excessive duty cycle, and avoid system instability caused by over-modulation. When it is detected that the target duty cycle is lower than the lower limit (that is, less than 0), it is automatically adjusted to 0 and the adjusted duty cycle is output to prevent invalid control due to excessively small duty cycle and avoid control instability caused by under-modulation.

[0152] For example, to help understand the technical concept or technical principle of this application, please refer to Figure 5 , Figure 5 The overall flow chart of the dead zone compensation control method is provided. First, the original duty cycle Duty_Svm and the compensation duty cycle Duty_dbc are calculated. If Duty_Svm is greater than Duty_X1 (the first partition threshold), the target duty cycle Duty_Final = Duty_Svm is finally issued. Otherwise, it is determined whether Duty_Svm is greater than Duty_X2 (the second partition threshold). If Duty_Svm>Duty_X2, it is determined whether Duty_dbc is greater than 0. If Duty_dbc>0, then If Duty_dbc≤0, then Duty_Final=Duty_Svm+Duty_dbc. If Duty_Svm≤Duty_X2, then determine whether Duty_Svm is less than the third partition threshold (1-Duty_X1). If Duty_Svm<1-Duty_X1, then Duty_Final=Duty_Svm. If Duty_Svm≥1-Duty_X1, then determine whether Duty_Svm is less than the fourth partition threshold (1-Duty_X2). If Duty_Svm<1-Duty_X2, then determine whether Duty_dbc is less than 0. If Duty_dbc<0, then If Duty_dbc≥0, then Duty_Final = Duty_Svm + Duty_dbc. If Duty_Svm≥1 - Duty_X2, then Duty_Final = Duty_Svm + Duty_dbc. After calculating the target duty cycle Duty_Final to be finally issued, it is judged whether Duty_Final is within the interval [0, 1]. If Duty_Final > 1, then Duty_Final = 1. If Duty_Final < 0, then Duty_Final = 0. In other cases, the original value is output and Duty_Final is applied to the PWM drive.

[0153] It should be noted that the above examples are only for understanding this application and do not constitute a limitation on the dead zone compensation control method of this application. Based on this technical concept, more forms of simple transformations are within the protection scope of this application.

[0154] This application also provides a dead zone compensation control system, which is applied to a motor control system. Please refer to Figure 6 , the dead zone compensation control system includes:

[0155] A calculation module 10, configured to obtain the original duty cycle of the motor control system through space vector pulse width modulation and calculate the compensation duty cycle for dead zone compensation in the motor control system;

[0156] A determination module 20, configured to determine the first partition threshold according to the minimum pulse width duty cycle of the motor control system, and determine the second partition threshold according to the minimum pulse width duty cycle and the dead zone duty cycle of the motor control system;

[0157] A partitioning module 30, configured to partition the duty cycle value range according to the first partition threshold and the second partition threshold to obtain each compensation sub-interval;

[0158] An adjustment module 40, configured to determine the target compensation sub-interval in which the original duty cycle is located among the compensation sub-intervals, and execute the duty cycle compensation strategy of the target compensation sub-interval to obtain the target duty cycle.

[0159] Optionally, the calculation module 10 is further configured to:

[0160] Determine the preset dead time and the on-delay and off-delay of the corresponding power switch tube according to the preset dead time table;

[0161] Determine the conduction voltage drop of the power switch tube and the conduction voltage drop of the diode according to the preset conduction voltage drop loss table, and determine the bus voltage and switching frequency of the motor control system;

[0162] Obtain the compensation duty cycle for dead-time compensation based on the preset dead-time, turn-on delay, turn-off delay, conduction voltage drop of the power switch tube, conduction voltage drop of the diode, bus voltage, and switching frequency.

[0163] Optionally, the calculation module 10 is further configured to:

[0164] Input the preset dead-time, turn-on delay, turn-off delay, conduction voltage drop of the power switch tube, conduction voltage drop of the diode, bus voltage, and switching frequency into a preset compensation formula to calculate the compensation duty cycle for dead-time compensation, where the preset compensation formula is:

[0165]

[0166] Duty_dbc is the compensation duty cycle, T d is the preset dead-time, T on is the turn-on delay, T off is the turn-off delay, U ce is the conduction voltage drop of the power switch tube, U f is the conduction voltage drop of the diode, U dc is the bus voltage, f pwm is the switching frequency.

[0167] Optionally, the determination module 20 is further configured to:

[0168] Calculate the minimum pulse-width duty cycle and the dead-time duty cycle of the motor control system, where the minimum pulse-width duty cycle is the product of the preset minimum pulse-width time and the switching frequency, and the dead-time duty cycle is the product of the preset dead-time and the switching frequency;

[0169] Take the difference between the upper bound of the duty cycle value range and the minimum pulse-width duty cycle as the first partition threshold;

[0170] Take the sum of the minimum pulse-width duty cycle and twice the dead-time duty cycle as the intermediate value, and take the difference between the upper bound of the duty cycle value range and the intermediate value as the second partition threshold.

[0171] Optionally, the duty cycle value range includes an upper bound and a lower bound, and the compensation sub-range includes a first compensation sub-range, a second compensation sub-range, a third compensation sub-range, a fourth compensation sub-range, and a fifth compensation sub-range. The partitioning module 30 is further configured to:

[0172] Denote the interval from the first partition threshold to the upper bound of the value as the first compensation sub-range, and denote the interval from the first partition threshold to the second partition threshold as the second compensation sub-range;

[0173] The interval from the numerical lower bound to the third partition threshold is denoted as the third compensation sub-interval, and the interval from the third partition threshold to the fourth partition threshold is denoted as the fourth compensation sub-interval, where the third partition threshold is the difference between the numerical upper bound and the first partition threshold, and the fourth partition threshold is the difference between the numerical upper bound and the second partition threshold;

[0174] The remaining interval in the duty cycle value range except for the first compensation sub-interval, the second compensation sub-interval, the third compensation sub-interval, and the fourth compensation sub-interval is used as the fifth compensation sub-interval.

[0175] Optionally, the adjustment module 40 is further configured to:

[0176] Step B01, when the target compensation sub-interval is the first compensation sub-interval or the third compensation sub-interval, use the original duty cycle as the target duty cycle;

[0177] When the target compensation sub-interval is the second compensation sub-interval, if the current polarity of the compensated duty cycle is positive, perform a linear attenuation process on the compensated duty cycle, and use the sum of the processed compensated duty cycle and the original duty cycle as the target duty cycle. If the current polarity of the compensated duty cycle is negative, use the sum of the compensated duty cycle and the original duty cycle as the target duty cycle;

[0178] When the target compensation sub-interval is the fourth compensation sub-interval, if the current polarity of the compensated duty cycle is negative, perform a linear attenuation process on the compensated duty cycle, and use the sum of the processed compensated duty cycle and the original duty cycle as the target duty cycle. If the current polarity of the compensated duty cycle is positive, use the sum of the compensated duty cycle and the original duty cycle as the target duty cycle;

[0179] When the target compensation sub-interval is the fifth compensation sub-interval, use the sum of the compensated duty cycle and the original duty cycle as the target duty cycle.

[0180] The dead zone compensation control system includes a calibration module 50, and the calibration module 50 is configured to:

[0181] Determine whether the target duty cycle is within the duty cycle value range;

[0182] In the case where the target duty cycle is greater than the numerical upper bound, adjust the target duty cycle to the numerical upper bound and output it;

[0183] In the case where the target duty cycle is less than the numerical lower bound, adjust the target duty cycle to the numerical lower bound and output it.

[0184] The dead-time compensation control device provided by this application adopts the dead-time compensation control method in the above embodiment, which can solve the technical problem of unstable compensation control. Compared with the prior art, the beneficial effects of the dead-time compensation control device provided by this application are the same as those of the dead-time compensation control method provided by the above embodiment, and other technical features in the dead-time compensation control device are the same as the features disclosed in the method of the above embodiment, which will not be elaborated here.

[0185] This application provides an electronic device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the dead-time compensation control method in the first embodiment above.

[0186] Refer to the following Figure 7 , which shows a schematic structural diagram of an electronic device suitable for implementing the embodiments of this application. The electronic device in the embodiments of this application may include, but is not limited to, mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), in-vehicle terminals (such as in-vehicle navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, printers, etc. Figure 7 The electronic device shown is only an example and should not impose any limitations on the functions and usage scope of the embodiments of this application.

[0187] As shown in Figure 7As shown, the electronic device may include a processing device 1001 (such as a central processing unit, a graphics processing unit, etc.), which may perform various appropriate actions and processes according to the program stored in the read-only memory 1002 or the program loaded from the storage device 1003 into the random access memory 1004. In the random access memory 1004, various programs and data required for the operation of the electronic device are also stored. The processing device 1001, the read-only memory 1002, and the random access memory 1004 are connected to each other through a bus 1005. The input / output interface 1006 is also connected to the bus. Generally, the following systems may be connected to the input / output interface 1006: an input device 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 may allow the electronic device to communicate with other devices wirelessly or wiredly to exchange data. Although the figure shows an electronic device having various systems, it should be understood that it is not required to implement or have all the shown systems. More or fewer systems may be implemented or had alternatively.

[0188] In particular, according to the embodiments disclosed in the present application, the processes described above with reference to the flowcharts may be implemented as computer software programs. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program contains program codes for performing the methods shown in the flowcharts. In such an embodiment, the computer program may be downloaded and installed from the network through the communication device, or installed from the storage device 1003, or installed from the read-only memory 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the methods of the embodiments disclosed in the present application are performed.

[0189] The electronic device provided in the present application adopts the dead zone compensation control method in the above embodiments, and can solve the technical problem of unstable compensation control. Compared with the prior art, the beneficial effects of the electronic device provided in the present application are the same as those of the dead zone compensation control method provided in the above embodiments, and other technical features in the electronic device are the same as those disclosed in the previous embodiment method, and will not be elaborated here.

[0190] It should be understood that each part disclosed in the present application may be implemented by hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0191] As described above, this is only the specific implementation of the present application. However, the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims described above.

[0192] The present application provides a computer-readable storage medium having computer-readable program instructions (i.e., computer programs) stored thereon, and the computer-readable program instructions are used to execute the dead zone compensation control method in the above embodiments.

[0193] The computer-readable storage medium provided by the present application can be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems or devices, or any combination of the above. More specific examples of the computer-readable storage medium may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM) or flash memory, optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above. In this embodiment, the computer-readable storage medium can be any tangible medium that contains or stores a program, and the program can be used by or in combination with an instruction execution system or device. The program code contained on the computer-readable storage medium can be transmitted by any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0194] The above computer-readable storage medium can be included in an electronic device; or it can exist alone without being assembled into the electronic device.

[0195] The above computer-readable storage medium carries one or more programs, which, when executed by an electronic device, enable the dead zone compensation control device to be applied to a motor control system, capable of obtaining the original duty cycle of the motor control system through space vector pulse width modulation and calculating the compensation duty cycle for dead zone compensation in the motor control system; determining a first partition threshold according to the minimum pulse width duty cycle of the motor control system, and determining a second partition threshold according to the minimum pulse width duty cycle and the dead zone duty cycle of the motor control system; dividing the duty cycle value range according to the first partition threshold and the second partition threshold to obtain each compensation sub-range; determining the target compensation sub-range in which the original duty cycle is located among the compensation sub-ranges, and executing the duty cycle compensation strategy of the target compensation sub-range to obtain the target duty cycle.

[0196] Computer program code for performing the operations of this application may be written in one or more programming languages or combinations thereof. The programming languages include object-oriented programming languages such as Java, Smalltalk, C++, and also include conventional procedural programming languages such as the "C" language or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, executed as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (for example, by using an Internet service provider to connect through the Internet).

[0197] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code that contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and the combination of blocks in the block diagram and / or flowchart, may be implemented by a dedicated hardware-based system for performing the specified functions or operations, or may be implemented by a combination of dedicated hardware and computer instructions.

[0198] The modules involved in the embodiments of the present application can be implemented in software or in hardware. In some cases, the name of the module does not constitute a limitation on the unit itself.

[0199] The readable storage medium provided by the present application is a computer-readable storage medium. The computer-readable storage medium stores computer-readable program instructions (i.e., computer programs) for executing the above dead zone compensation control method, which can solve the technical problem of unstable compensation control. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided by the present application are the same as those of the dead zone compensation control method provided by the above embodiments, and will not be elaborated here.

[0200] The present application also provides a computer program product, including a computer program, and the steps of the above dead zone compensation control method are implemented when the computer program is executed by a processor.

[0201] The computer program product provided by the present application can solve the technical problem of unstable compensation control. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as those of the dead zone compensation control method provided by the above embodiments, and will not be elaborated here.

[0202] The above are only some embodiments of the present application, and thus do not limit the patent scope of the present application. Any equivalent structural transformation made by using the content of the specification and drawings of the present application under the technical concept of the present application, or any direct / indirect application in other related technical fields, is included in the patent protection scope of the present application.

Claims

1. A dead zone compensation control method, characterized in that: Applied to a motor control system, the dead zone compensation control method includes: Acquiring an original duty cycle of the motor control system by space vector pulse width modulation, and calculating a compensated duty cycle for dead zone compensation in the motor control system; Determine a first partition threshold value according to a minimum pulse width duty cycle of the motor control system, and determine a second partition threshold value according to the minimum pulse width duty cycle and a dead zone duty cycle of the motor control system; Dividing the duty cycle value interval according to the first partition threshold and the second partition threshold to obtain compensation sub-intervals; A target compensation sub-interval in which the original duty cycle is located in each compensation sub-interval is determined, and a duty cycle compensation strategy of the target compensation sub-interval is executed to obtain a target duty cycle.

2. The dead zone compensation control method according to claim 1, characterized in that: The step of calculating the compensation duty ratio for dead zone compensation in the motor control system comprises: Determine the preset dead time and the turn-on delay and turn-off delay of the corresponding power switch tube according to the preset dead time schedule; Determine the conduction voltage drop of the power switch tube and the conduction voltage drop of the diode according to a preset conduction voltage drop loss table, and determine the bus voltage and switching frequency of the motor control system; A compensation duty ratio for dead zone compensation is obtained according to the preset dead time, the turn-on delay, the turn-off delay, the conduction voltage drop of the power switch tube, the conduction voltage drop of the diode, the bus voltage and the switching frequency.

3. The dead zone compensation control method according to claim 2, characterized in that: The step of obtaining a compensation duty ratio for dead zone compensation according to the preset dead zone time, the turn-on delay, the turn-off delay, the conduction voltage drop of the power switch tube, the conduction voltage drop of the diode, the bus voltage and the switching frequency comprises: The preset dead time, the turn-on delay, the turn-off delay, the power switch tube conduction voltage drop, the diode conduction voltage drop, the bus voltage and the switching frequency are input into a preset compensation formula to calculate the compensation duty ratio for dead time compensation, wherein the preset compensation formula is: Duty_dbc is the compensation duty cycle, T d is the preset dead time, T on is the opening delay, T off is the shutdown delay, U ce is the conduction voltage drop of the power switch tube, U f is the diode conduction voltage drop, U dc is the bus voltage, f pwm is the switching frequency.

4. The dead zone compensation control method according to claim 2, characterized in that: The steps of determining the first partition threshold according to the minimum pulse width duty cycle of the motor control system and determining the second partition threshold according to the minimum pulse width duty cycle and the dead zone duty cycle of the motor control system include: Calculating a minimum pulse width duty cycle and a dead zone duty cycle of the motor control system, wherein the minimum pulse width duty cycle is the product of a preset minimum pulse width time and the switching frequency, and the dead zone duty cycle is the product of the preset dead zone time and the switching frequency; The difference between the upper limit of the duty cycle value interval and the minimum pulse width duty cycle is used as the first partition threshold; The sum of the minimum pulse width duty cycle and twice the dead zone duty cycle is taken as an intermediate value, and the difference between the upper limit of the duty cycle value interval and the intermediate value is taken as a second partition threshold.

5. The dead zone compensation control method according to claim 1, characterized in that: The duty cycle value interval includes a numerical upper bound and a numerical lower bound, the compensation subinterval includes a first compensation subinterval, a second compensation subinterval, a third compensation subinterval, a fourth compensation subinterval, and a fifth compensation subinterval, and the step of dividing the duty cycle value interval according to the first partition threshold and the second partition threshold to obtain each compensation subinterval includes: The interval from the first partition threshold to the upper limit of the value is recorded as a first compensation sub-interval, and the interval from the first partition threshold to the second partition threshold is recorded as a second compensation sub-interval; The interval from the numerical lower bound to the third partition threshold is recorded as a third compensation sub-interval, and the interval from the third partition threshold to the fourth partition threshold is recorded as a fourth compensation sub-interval, wherein the third partition threshold is the difference between the numerical upper bound and the first partition threshold, and the fourth partition threshold is the difference between the numerical upper bound and the second partition threshold; The remaining interval of the duty cycle value interval except the first compensation sub-interval, the second compensation sub-interval, the third compensation sub-interval and the fourth compensation sub-interval is used as a fifth compensation sub-interval.

6. The dead zone compensation control method according to claim 5, characterized in that: The step of determining the target compensation sub-interval in which the original duty cycle is located in each compensation sub-interval, and executing the duty cycle compensation strategy of the target compensation sub-interval to obtain the target duty cycle includes: When the target compensation sub-interval is the first compensation sub-interval or the third compensation sub-interval, taking the original duty cycle as the target duty cycle; When the target compensation sub-interval is the second compensation sub-interval, if the current polarity of the compensation duty cycle is positive, the compensation duty cycle is subjected to linear attenuation processing, and the sum of the processed compensation duty cycle and the original duty cycle is used as the target duty cycle; if the current polarity of the compensation duty cycle is negative, the sum of the compensation duty cycle and the original duty cycle is used as the target duty cycle; When the target compensation sub-interval is the fourth compensation sub-interval, if the current polarity of the compensation duty cycle is negative, the compensation duty cycle is subjected to linear attenuation processing, and the sum of the processed compensation duty cycle and the original duty cycle is used as the target duty cycle; if the current polarity of the compensation duty cycle is positive, the sum of the compensation duty cycle and the original duty cycle is used as the target duty cycle; When the target compensation sub-interval is the fifth compensation sub-interval, the sum of the compensated duty cycle and the original duty cycle is used as the target duty cycle.

7. The dead zone compensation control method according to claim 5, characterized in that: After the step of executing the duty cycle compensation strategy of the target compensation sub-interval to obtain the target duty cycle, the method further includes: Determining whether the target duty cycle is within the duty cycle value interval; When the target duty cycle is greater than the upper limit of the numerical value, adjusting the target duty cycle to the upper limit of the numerical value and outputting the result; When the target duty cycle is smaller than the numerical lower limit, the target duty cycle is adjusted to the numerical lower limit and output.

8. An electronic device, characterized in that: The device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the dead zone compensation control method according to any one of claims 1 to 7.

9. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the dead zone compensation control method according to any one of claims 1 to 7 are implemented.

10. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the steps of the dead zone compensation control method according to any one of claims 1 to 7 are implemented.

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