Vehicle bus ripple suppression method and device

Abstract

The invention relates to the technical field of motor control, in particular to a vehicle bus ripple suppression method and device, and the method comprises the steps: obtaining the current switching frequency and the current duty ratio of a three-phase inverter of a motor, determining all connection moments and disconnection moments of upper and lower bridge arms of each phase of the three-phase inverter of the motor, and determining the optimal switching frequency and the optimal duty ratio of a DC-DC converter of a power supply system of the vehicle for suppressing the bus ripples so as to prohibit the DC-DC converter and a motor three-phase inverter from being switched on or switched off at the same time. According to the embodiment of the invention, the switching frequency and duty ratio of the switching device in the DC-DC converter of the vehicle-mounted power supply can be adjusted based on the working state of the three-phase inverter, so as to avoid the moment when the switching device and the DC-DC converter are turned on or off simultaneously, thereby improving the suppression efficiency of the ripple amplitude of the bus capacitor, guaranteeing the quality of voltage and current output by the bus, and improving the reliability of the vehicle-mounted power supply. The control cost is reduced, and the practicability is higher.

Description

Technical Field

[0001] The present application relates to the field of motor control technology, and in particular to a method and device for suppressing vehicle bus ripple. Background Art

[0002] During vehicle driving, the motor's three-phase inverter and the power supply DC-DC converter operate simultaneously, and their switching devices are often turned on or off at the same time, resulting in the superposition of the fundamental wave and carrier of the motor and power supply system, and an increase in the ripple amplitude of the bus capacitor, posing a risk of bus capacitor overvoltage.

[0003] In the related technology, the bus ripple bearing capacity can be improved by increasing the capacitance. For example, patent CN113572353A constructs an active network topology based on power electronic switching devices to isolate the energy storage capacitor and the DC bus, increases the voltage pulsation of the energy storage capacitor by shifting the position of the energy storage capacitor, constructs a non-electrolytic capacitor, and realizes ripple transfer.

[0004] However, in the related technology, increasing the capacitance will increase the volume and mass of the capacitor, making the system more difficult and complicated to arrange and install, while increasing the production and manufacturing cost of the entire vehicle. It is impossible to achieve a convenient and efficient bus ripple suppression effect, which affects the quality of the bus output voltage and current and reduces the EMC (Electro Magnetic Compatibility) performance of the system, which needs to be solved urgently. Summary of the invention

[0005] The present application provides a method and device for suppressing vehicle bus ripple to solve the problem in the related art that increasing the capacitor will increase the volume and mass of the capacitor, making the system more difficult and cumbersome to arrange and install, while increasing the production and manufacturing cost of the entire vehicle, failing to achieve a convenient and efficient bus ripple suppression effect, affecting the quality of the bus output voltage and current, and reducing the EMC performance of the system.

[0006] The first aspect of the present application provides a method for suppressing vehicle bus ripple, comprising the following steps: obtaining a current switching frequency and a current duty cycle of a motor three-phase inverter; determining all turn-on moments and all turn-off moments of upper and lower bridge arms of each phase of the motor three-phase inverter according to the current switching frequency and the current duty cycle of the motor three-phase inverter; and determining an optimal switching frequency and an optimal duty cycle of a DC-DC converter of a power supply system of the vehicle for suppressing bus ripple based on all turn-on moments and all turn-off moments of upper and lower bridge arms of each phase of the motor three-phase inverter, so as to prohibit the DC-DC converter and the motor three-phase inverter from being turned on or off at the same time.

[0007] According to the above-mentioned technical means, the embodiment of the present application can adjust the switching frequency and duty cycle of the switching devices in the on-board power supply DC-DC converter based on the working state of the three-phase inverter to avoid the two being turned on or off at the same time at staggered times, thereby improving the efficiency of suppressing the bus capacitor ripple amplitude, ensuring the output voltage and current quality of the bus output, reducing control costs, and being more practical.

[0008] Optionally, in one embodiment of the present application, obtaining the switching frequency and duty cycle of the three-phase inverter includes: obtaining the actual operating condition and frequency conversion strategy of the vehicle's motor; calculating the transistor switching frequency and duty cycle of the motor's three-phase inverter according to the actual operating condition and frequency conversion strategy, and determining the current switching frequency and the current duty cycle.

[0009] According to the above-mentioned technical means, the embodiment of the present application can obtain the actual operating condition and frequency conversion strategy of the vehicle's motor, calculate the transistor switching frequency and duty cycle of the motor's three-phase inverter according to the actual operating condition and frequency conversion strategy, determine the current switching frequency and the current duty cycle, and further confirm the turn-on and turn-off times of the three-phase inverter switching elements.

[0010] Optionally, in one embodiment of the present application, before adjusting the switching frequency and duty cycle of the DC-DC converter of the power system, it includes: obtaining the pulse width modulation duty cycle and switching frequency of the switching device in the Buck circuit of the DC-DC converter of the power system.

[0011] According to the above-mentioned technical means, the embodiment of the present application can obtain the pulse width modulation duty cycle and switching frequency of the switching device in the Buck circuit of the DC-DC converter of the power system before adjusting the switching frequency and duty cycle of the DC-DC converter of the power system, so as to adjust the duty cycle and switching frequency of the power system according to the conduction and disconnection moments of the switching elements of the three-phase inverter, thereby suppressing the ripple amplitude of the bus capacitor and improving the safety management efficiency of the vehicle.

[0012] Optionally, in one embodiment of the present application, the optimal switching frequency and optimal duty cycle of the DC-DC converter of the power system of the vehicle that suppresses bus ripple are determined based on all the turn-on moments and all the turn-off moments of the upper and lower bridge arms of each phase of the three-phase inverter of the motor, including: determining the simultaneous turn-on moment or the simultaneous turn-off moment of the DC-DC converter and the three-phase inverter, generating the optimal switching frequency and the optimal duty cycle according to the simultaneous turn-on moment or the simultaneous turn-off moment, and adjusting the switching frequency and duty cycle of the DC-DC converter of the power system so that the two are staggered at the simultaneous turn-on moment or the simultaneous turn-off moment; or, determining the simultaneous turn-on moment or the simultaneous turn-off moment of the DC-DC converter and the three-phase inverter, generating the optimal switching frequency and the optimal duty cycle according to the simultaneous turn-on moment or the simultaneous turn-off moment, and adjusting the switching frequency and duty cycle of the DC-DC converter of the power system so that the DC-DC converter of the power system performs the opposite action at the simultaneous turn-on moment or the simultaneous turn-off moment.

[0013] According to the above-mentioned technical means, the embodiment of the present application can control the frequency and duty cycle of the switching device PWM of the DC-DC converter Buck circuit to adjust it so that it is staggered with the turn-on or turn-off time of the three-phase inverter or performs a reverse action, thereby efficiently realizing the bus ripple amplitude suppression process and simplifying the vehicle structure.

[0014] The second aspect of the present application provides a vehicle bus ripple suppression device, including: an acquisition module, used to acquire the current switching frequency and the current duty cycle of the motor three-phase inverter; a confirmation module, used to determine all turn-on moments and all turn-off moments of the upper and lower bridge arms of each phase of the motor three-phase inverter according to the current switching frequency and the current duty cycle of the motor three-phase inverter; a suppression module, used to determine the optimal switching frequency and optimal duty cycle of the DC-DC converter of the vehicle's power supply system for suppressing bus ripple based on all turn-on moments and all turn-off moments of the upper and lower bridge arms of each phase of the motor three-phase inverter, so as to prohibit the DC-DC converter and the motor three-phase inverter from being turned on or off at the same time.

[0015] Optionally, in one embodiment of the present application, the acquisition module includes: a first acquisition unit, used to acquire the actual operating condition and frequency conversion strategy of the vehicle's motor; a calculation unit, used to calculate the transistor switching frequency and duty cycle of the motor's three-phase inverter based on the actual operating condition and frequency conversion strategy, and determine the current switching frequency and the current duty cycle.

[0016] Optionally, in one embodiment of the present application, the suppression module includes: a second acquisition unit, used to obtain the pulse width modulation duty cycle and switching frequency of the switching device in the Buck circuit of the DC-DC converter of the power system before adjusting the switching frequency and duty cycle of the DC-DC converter of the power system.

[0017] Optionally, in one embodiment of the present application, the suppression module includes: a first adjustment unit, used to determine the simultaneous turn-on moment or the simultaneous turn-off moment of the DC-DC converter and the three-phase inverter, generate the optimal switching frequency and the optimal duty cycle according to the simultaneous turn-on moment or the simultaneous turn-off moment, and adjust the switching frequency and duty cycle of the DC-DC converter of the power supply system so that the two are staggered by the simultaneous turn-on moment or the simultaneous turn-off moment; or, a second adjustment unit, used to determine the simultaneous turn-on moment or the simultaneous turn-off moment of the DC-DC converter and the three-phase inverter, generate the optimal switching frequency and the optimal duty cycle according to the simultaneous turn-on moment or the simultaneous turn-off moment, and adjust the switching frequency and duty cycle of the DC-DC converter of the power supply system so that the DC-DC converter of the power supply system performs the opposite action at the simultaneous turn-on moment or the simultaneous turn-off moment.

[0018] A third aspect of the present application provides a vehicle, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the vehicle bus ripple suppression method as described in the above embodiment.

[0019] A fourth aspect of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, which, when executed by a processor, implements the above-mentioned method for suppressing vehicle bus ripple.

[0020] Beneficial effects of this application:

[0021] (1) The switching frequency and duty cycle of the switching devices in the on-board power supply DC-DC converter can be adjusted based on the working state of the three-phase inverter to avoid the two being turned on or off at the same time, thereby improving the efficiency of suppressing the bus capacitor ripple amplitude, ensuring the output voltage and current quality of the bus, reducing the control cost, and making it more practical.

[0022] (2) The embodiment of the present application can control the frequency and duty cycle of the switching device PWM of the DC-DC converter Buck circuit to adjust it so that it is staggered with the turn-on or turn-off time of the three-phase inverter or performs a reverse action, thereby efficiently realizing the bus ripple amplitude suppression process and simplifying the vehicle structure.

[0023] (3) The embodiment of the present application can obtain the pulse width modulation duty cycle and switching frequency of the switching device in the Buck circuit of the DC-DC converter of the power system before adjusting the switching frequency and duty cycle of the DC-DC converter of the power system, so as to adjust the duty cycle and switching frequency of the power system according to the turn-on and turn-off moments of the switching elements of the three-phase inverter, thereby suppressing the ripple amplitude of the bus capacitor and improving the safety management efficiency of the vehicle.

[0024] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0026] Figure 1 A flowchart of a method for suppressing vehicle bus ripple provided according to an embodiment of the present application;

[0027] Figure 2 A schematic diagram of a vehicle bus ripple suppression process according to an embodiment of the present application;

[0028] Figure 3 A pulse width modulation timing control schematic diagram of a motor and power supply system according to an embodiment of the present application;

[0029] Figure 4 Schematic diagram of the structure of a vehicle busbar ripple suppression device according to an embodiment of the present application;

[0030] Figure 5 It is a schematic diagram of the structure of a vehicle according to an embodiment of the present application.

[0031] Among them, 10 is a vehicle bus ripple suppression device; 100 is an acquisition module, 200 is a confirmation module and 300 is a suppression module; 501 is a memory, 502 is a processor and 503 is a communication interface. DETAILED DESCRIPTION

[0032] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0033] The following describes the vehicle bus ripple suppression method and device of the embodiment of the present application with reference to the accompanying drawings. In view of the above-mentioned related art mentioned in the background technology, increasing the capacitance will increase the volume and mass of the capacitance, making the system more difficult and cumbersome when arranged and installed, and at the same time increasing the production and manufacturing cost of the whole vehicle, it is impossible to achieve a convenient and efficient bus ripple suppression effect, affecting the quality of the bus output voltage and current, and reducing the EMC performance of the system. The present application provides a vehicle bus ripple suppression method, which can adjust the switching frequency and duty cycle of the switching device in the vehicle power DC-DC converter based on the working state of the three-phase inverter to avoid the two being staggered and turned on or off at the same time, thereby improving the bus capacitor ripple amplitude suppression efficiency, ensuring the bus output voltage and current quality, reducing the control cost, and being more practical. Thus, it solves the problem that increasing the capacitance in the related art will increase the volume and mass of the capacitance, making the system more difficult and cumbersome when arranged and installed, and at the same time increasing the production and manufacturing cost of the whole vehicle, it is impossible to achieve a convenient and efficient bus ripple suppression effect, affecting the quality of the bus output voltage and current, and reducing the EMC performance of the system.

[0034] Specifically, Figure 1 A schematic flow chart of a method for suppressing vehicle bus ripple provided in an embodiment of the present application.

[0035] like Figure 1 As shown, the method for suppressing vehicle bus ripples includes the following steps:

[0036] In step S101 , the current switching frequency and the current duty cycle of the three-phase inverter of the motor are obtained.

[0037] It can be understood that in the embodiment of the present application, the motor three-phase inverter can be used to control the motor drive, the switching frequency refers to the switching frequency of the switching element in the motor three-phase inverter, that is, the frequency of the switching action, and the duty cycle can be the ratio of the time when the switching element is turned on in one cycle to the total cycle time. For example, the switching frequency can be determined by detecting the on and off states of the switching element, and the current duty cycle can be calculated based on the on time of the switching element and the total cycle time.

[0038] Optionally, in one embodiment of the present application, the switching frequency and duty cycle of the three-phase inverter are obtained, including: obtaining the actual operating condition and frequency conversion strategy of the vehicle's motor; calculating the transistor switching frequency and duty cycle of the motor's three-phase inverter according to the actual operating condition and frequency conversion strategy, and determining the current switching frequency and the current duty cycle.

[0039] In some embodiments, the switching frequency and duty cycle of the insulated gate bipolar transistor IGBT, a switching element of the motor's three-phase inverter, can be calculated using a space vector pulse width modulation algorithm SVPWM according to the motor's current actual operating conditions and frequency conversion strategy.

[0040] The embodiment of the present application can obtain the actual operating condition and frequency conversion strategy of the vehicle's motor, calculate the transistor switching frequency and duty cycle of the motor's three-phase inverter based on the actual operating condition and frequency conversion strategy, determine the current switching frequency and the current duty cycle, and further confirm the turn-on and turn-off times of the three-phase inverter switching elements.

[0041] In step S102, all the on-times and all the off-times of the upper and lower bridge arms of each phase of the three-phase inverter of the motor are determined according to the current switching frequency and the current duty cycle of the three-phase inverter of the motor.

[0042] In the actual implementation process, after the switching frequency and duty cycle of the motor's three-phase inverter IGBT are calculated by the SVPWM algorithm according to the motor's current operating conditions and frequency conversion strategy, the switching sequence of the three-phase inverter bridge arm within one cycle can be further obtained according to the sector where the voltage space vector is located. The three phases of the motor inverter are switched in sequence, thereby calculating the turn-on and turn-off moments of each phase within one cycle, that is, obtaining all the turn-on moments and all the turn-off moments of the upper and lower bridge arms of each phase of the motor's three-phase inverter.

[0043] In step S103, based on all the turn-on moments and all the turn-off moments of the upper and lower bridge arms of each phase of the three-phase inverter of the motor, the optimal switching frequency and the optimal duty cycle of the DC-DC converter of the power system of the vehicle for suppressing bus ripple are determined to prohibit the DC-DC converter and the three-phase inverter of the motor from being turned on or off at the same time.

[0044] It can be understood that in the embodiments of the present application, the optimal switching frequency and optimal duty cycle of the DC-DC converter of the vehicle power system ultimately determined can avoid the situation where the DC-DC converter and the motor three-phase inverter are turned on or off at the same time, and prevent the fundamental wave and carrier of the vehicle's motor and power system from being superimposed, resulting in an increase in the bus ripple amplitude, so as to ensure the smooth transmission of vehicle current and voltage.

[0045] In particular, the vehicle's motor and power system can be deeply integrated, using the same single-chip microcomputer to drive the power supply and motor controller to ensure that the internal closed-loop control in the DC-DC converter can be adjusted in real time, thereby ensuring the efficiency of suppressing the bus ripple amplitude.

[0046] Optionally, in one embodiment of the present application, before adjusting the switching frequency and duty cycle of the DC-DC converter of the power system, it includes: obtaining the pulse width modulation duty cycle and switching frequency of the switching device in the Buck circuit of the DC-DC converter of the power system.

[0047] In the actual implementation process, the duty cycle and switching frequency of the pulse width modulation PWM (Pulse Width Modulation) of the switching device in the DC-DC converter Buck circuit of the power system can be obtained. In the steady-state condition, the frequency and duty cycle are usually fixed values.

[0048] The embodiment of the present application can obtain the pulse width modulation duty cycle and switching frequency of the switching device in the Buck circuit of the DC-DC converter of the power system before adjusting the switching frequency and duty cycle of the DC-DC converter of the power system, so as to adjust the duty cycle and switching frequency of the power system according to the turn-on and turn-off moments of the switching elements of the three-phase inverter, thereby suppressing the ripple amplitude of the bus capacitor and improving the safety management efficiency of the vehicle.

[0049] Optionally, in one embodiment of the present application, based on all turn-on moments and all turn-off moments of the upper and lower bridge arms of each phase of the three-phase inverter of the motor, the optimal switching frequency and the optimal duty cycle of the DC-DC converter of the power system of the vehicle that suppresses bus ripple are determined, including: determining the simultaneous turn-on moment or the simultaneous turn-off moment of the DC-DC converter and the three-phase inverter, generating the optimal switching frequency and the optimal duty cycle according to the simultaneous turn-on moment or the simultaneous turn-off moment, and adjusting the switching frequency and the duty cycle of the DC-DC converter of the power system so that the two stagger the simultaneous turn-on moment or the simultaneous turn-off moment; or, determining the simultaneous turn-on moment or the simultaneous turn-off moment of the DC-DC converter and the three-phase inverter, generating the optimal switching frequency and the optimal duty cycle according to the simultaneous turn-on moment or the simultaneous turn-off moment, and adjusting the switching frequency and the duty cycle of the DC-DC converter of the power system so that the DC-DC converter of the power system performs the opposite action at the simultaneous turn-on moment or the simultaneous turn-off moment.

[0050] It is understandable that in the embodiments of the present application, the frequency and duty cycle of the PWM of the switching device of the DC-DC converter Buck circuit can be adjusted according to the switching moment of each phase bridge arm of the three-phase inverter of the motor, so as to stagger the moment of simultaneous conduction or shutdown with any phase of the three-phase inverter, or make the two as many opposite actions as possible at the switching moment to offset the influence on the bus, so as to reduce the ripple amplitude generated by superposition. After adjustment, the bus ripples generated by the three-phase inverter IGBT of the motor and the power supply DC-DC converter Buck circuit can produce a phase difference or offset each other, and the bus ripple amplitude generated by superposition will be lower than before adjustment. Among them, the PWM frequency adjustment of the switching device of the DC-DC converter Buck circuit is within the allowable range, and the DC-DC output power before and after the adjustment remains unchanged.

[0051] The embodiment of the present application can control the frequency and duty cycle of the DC-DC converter Buck circuit switching device PWM to adjust it so that it is staggered with the turn-on or turn-off time of the three-phase inverter or performs a reverse action, thereby efficiently realizing the bus ripple amplitude suppression process and simplifying the vehicle structure.

[0052] like Figure 2 As shown, the working content of the embodiment of the present application is described in detail below with a specific embodiment.

[0053] Step S201: Obtain control parameters such as the switching frequency and duty cycle of the IGBT power device of the motor controller in the current working condition.

[0054] Step S202: Obtain the PWM frequency and duty cycle of the DC-DC converter Buck circuit of the power system.

[0055] Step S203: adjusting the frequency and duty cycle of the DC-DC converter Buck circuit PWM to stagger the simultaneous on or off moments of the two, or to make them cancel each other out, thereby reducing bus ripple.

[0056] Specifically, Figure 3 As shown, taking the motor space voltage vector in the first sector as an example, Figure 3 (a) is the waveform diagram of the three-phase inverter. Figure 3(b) is the waveform diagram of the Buck circuit of the power system, the upper part is the waveform before the power system is optimized, and the lower part is the waveform after the power system is optimized. If a phase in the three-phase inverter and the Buck circuit switch device are turned on at the same time at t1, t2, and t3, the PWM frequency and duty cycle of the Buck circuit switch device are adjusted so that the two are not turned on at the same time, and the control at the turn-off time is similar to that at the turn-on time; or by adjusting the Buck circuit PWM frequency and duty cycle, the Buck circuit switch device can make the opposite action of the three-phase inverter IGBT, that is, when a phase of the inverter is turned on, the Buck circuit is controlled to be turned off, or when a phase of the inverter is turned off, the Buck circuit is controlled to be turned on, which is similar to the control effect at t4, t5, and t6.

[0057] According to the vehicle bus ripple suppression method proposed in the embodiment of the present application, the switching frequency and duty cycle of the switching device in the vehicle power DC-DC converter can be adjusted based on the working state of the three-phase inverter to avoid the two being staggered and turned on or off at the same time, thereby improving the suppression efficiency of the bus capacitor ripple amplitude, ensuring the output voltage and current quality of the bus output, reducing the control cost, and being more practical. Thus, the problem that increasing the capacitance in the related technology will increase the volume and mass of the capacitance, making the system more difficult and cumbersome to arrange and install, while increasing the production and manufacturing cost of the whole vehicle, failing to achieve a convenient and efficient bus ripple suppression effect, affecting the quality of the bus output voltage and current, and reducing the EMC performance of the system is solved.

[0058] Next, a vehicle bus ripple suppression device proposed according to an embodiment of the present application will be described with reference to the accompanying drawings.

[0059] Figure 4 It is a schematic diagram of the structure of a vehicle busbar ripple suppression device according to an embodiment of the present application.

[0060] like Figure 4 As shown, the vehicle bus ripple suppression device 10 includes: an acquisition module 100 , a confirmation module 200 and a suppression module 300 .

[0061] Wherein, the acquisition module 100 is used to acquire the current switching frequency and current duty cycle of the motor three-phase inverter;

[0062] The confirmation module 200 is used to determine all the on-times and all the off-times of the upper and lower bridge arms of each phase of the three-phase inverter of the motor according to the current switching frequency and the current duty cycle of the three-phase inverter of the motor.

[0063] The suppression module 300 is used to determine the optimal switching frequency and optimal duty cycle of the DC-DC converter of the vehicle power system for suppressing bus ripple based on all the turn-on moments and all the turn-off moments of the upper and lower bridge arms of each phase of the three-phase inverter of the motor, so as to prohibit the DC-DC converter and the three-phase inverter of the motor from being turned on or turned off at the same time.

[0064] Optionally, in one embodiment of the present application, the acquisition module 100 includes: a first acquisition unit and a calculation unit.

[0065] Wherein, the first acquisition unit is used to acquire the actual working condition and frequency conversion strategy of the motor of the vehicle.

[0066] The calculation unit is used to calculate the transistor switching frequency and duty cycle of the motor three-phase inverter according to the actual working condition and the frequency conversion strategy, and determine the current switching frequency and the current duty cycle.

[0067] Optionally, in one embodiment of the present application, the suppression module 300 includes: a second acquisition unit.

[0068] The second acquisition unit is used to acquire the pulse width modulation duty cycle and switching frequency of the switching device in the Buck circuit of the DC-DC converter of the power system before adjusting the switching frequency and duty cycle of the DC-DC converter of the power system.

[0069] Optionally, in one embodiment of the present application, the suppression module 300 includes: a first adjustment unit and a second adjustment unit.

[0070] Among them, the first adjustment unit is used to determine the simultaneous turn-on time or simultaneous turn-off time of the DC-DC converter and the three-phase inverter, generate the optimal switching frequency and the optimal duty cycle according to the simultaneous turn-on time or the simultaneous turn-off time, and adjust the switching frequency and duty cycle of the DC-DC converter of the power supply system so that the two stagger the simultaneous turn-on time or the simultaneous turn-off time.

[0071] Alternatively, a second adjustment unit is used to determine the simultaneous turn-on moment or the simultaneous turn-off moment of the DC-DC converter and the three-phase inverter, generate an optimal switching frequency and an optimal duty cycle according to the simultaneous turn-on moment or the simultaneous turn-off moment, and adjust the switching frequency and duty cycle of the DC-DC converter of the power supply system so that the DC-DC converter of the power supply system performs opposite actions at the simultaneous turn-on moment or the simultaneous turn-off moment.

[0072] It should be noted that the above explanation of the embodiment of the vehicle bus ripple suppression method is also applicable to the vehicle bus ripple suppression device of this embodiment, and will not be repeated here.

[0073] According to the vehicle bus ripple suppression device proposed in the embodiment of the present application, the switching frequency and duty cycle of the switching device in the vehicle power DC-DC converter can be adjusted based on the working state of the three-phase inverter to avoid the two being staggered and turned on or off at the same time, thereby improving the suppression efficiency of the bus capacitor ripple amplitude, ensuring the output voltage and current quality of the bus output, reducing the control cost, and being more practical. As a result, the problem that increasing the capacitance in the related technology will increase the volume and mass of the capacitance, making the system more difficult and cumbersome to arrange and install, while increasing the production and manufacturing cost of the whole vehicle, failing to achieve a convenient and efficient bus ripple suppression effect, affecting the quality of the bus output voltage and current, and reducing the EMC performance of the system.

[0074] Figure 5 A schematic diagram of the structure of a vehicle provided in an embodiment of the present application. The vehicle may include:

[0075] A memory 501 , a processor 502 , and a computer program stored in the memory 501 and executable on the processor 502 .

[0076] When the processor 502 executes the program, the vehicle bus ripple suppression method provided in the above embodiment is implemented.

[0077] Furthermore, the vehicle also includes:

[0078] The communication interface 503 is used for communication between the memory 501 and the processor 502 .

[0079] The memory 501 is used to store computer programs that can be executed on the processor 502 .

[0080] The memory 501 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0081] If the memory 501, the processor 502 and the communication interface 503 are implemented independently, the communication interface 503, the memory 501 and the processor 502 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 5 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0082] Optionally, in a specific implementation, if the memory 501, the processor 502 and the communication interface 503 are integrated on a chip, the memory 501, the processor 502 and the communication interface 503 can communicate with each other through an internal interface.

[0083] The processor 502 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0084] This embodiment also provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the above-mentioned vehicle bus ripple suppression method is implemented.

[0085] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0086] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0087] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0088] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or N wirings (electronic devices), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways as necessary and then storing it in a computer memory.

[0089] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0090] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0091] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0092] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for suppressing vehicle bus ripple, characterized in that: The following steps are involved: Get the current switching frequency and current duty cycle of the motor three-phase inverter; Determine all the on-times and all the off-times of the upper and lower bridge arms of each phase of the three-phase inverter of the motor according to the current switching frequency and the current duty cycle of the three-phase inverter of the motor; and Based on all the turn-on moments and all the turn-off moments of the upper and lower bridge arms of each phase of the three-phase inverter of the motor, the optimal switching frequency and the optimal duty cycle of the DC-DC converter of the power system of the vehicle for suppressing bus ripple are determined to prohibit the DC-DC converter and the three-phase inverter of the motor from being turned on or off at the same time.

2. The method according to claim 1, characterized in that The obtaining of the switching frequency and duty cycle of the three-phase inverter includes: Obtaining the actual operating condition and frequency conversion strategy of the motor of the vehicle; The transistor switching frequency and duty cycle of the three-phase inverter of the motor are calculated according to the actual working condition and the frequency conversion strategy, and the current switching frequency and the current duty cycle are determined.

3. The method according to claim 1, characterized in that Before adjusting the switching frequency and duty cycle of the DC-DC converter of the power supply system, the method includes: The pulse width modulation duty cycle and switching frequency of the switching device in the Buck circuit of the DC-DC converter of the power supply system are obtained.

4. The method according to claim 1, characterized in that The method of determining the optimal switching frequency and the optimal duty cycle of the DC-DC converter of the power system of the vehicle for suppressing bus ripple based on all the on-times and all the off-times of the upper and lower bridge arms of each phase of the three-phase inverter of the motor comprises: Determine a simultaneous turn-on moment or a simultaneous turn-off moment of the DC-DC converter and the three-phase inverter, generate the optimal switching frequency and the optimal duty cycle according to the simultaneous turn-on moment or the simultaneous turn-off moment, and adjust the switching frequency and the duty cycle of the DC-DC converter of the power supply system so that the two stagger the simultaneous turn-on moment or the simultaneous turn-off moment; Alternatively, the simultaneous turn-on moment or the simultaneous turn-off moment of the DC-DC converter and the three-phase inverter is determined, the optimal switching frequency and the optimal duty cycle are generated according to the simultaneous turn-on moment or the simultaneous turn-off moment, and the switching frequency and the duty cycle of the DC-DC converter of the power supply system are adjusted so that the DC-DC converter of the power supply system performs the opposite action at the simultaneous turn-on moment or the simultaneous turn-off moment.

5. A vehicle busbar ripple suppression device, characterized in that: include: An acquisition module is used to acquire the current switching frequency and current duty cycle of the motor three-phase inverter; A confirmation module, used to determine all the on-times and all the off-times of the upper and lower bridge arms of each phase of the three-phase inverter of the motor according to the current switching frequency and the current duty cycle of the three-phase inverter of the motor; as well as A suppression module is used to determine the optimal switching frequency and optimal duty cycle of the DC-DC converter of the vehicle power system for suppressing bus ripple based on all turn-on moments and all turn-off moments of the upper and lower bridge arms of each phase of the three-phase inverter of the motor, so as to prohibit the DC-DC converter and the three-phase inverter of the motor from being turned on or turned off at the same time.

6. The device according to claim 5, characterized in that The acquisition module comprises: A first acquisition unit, used to acquire the actual working condition and frequency conversion strategy of the motor of the vehicle; A calculation unit is used to calculate the transistor switching frequency and duty cycle of the three-phase inverter of the motor according to the actual working condition and the frequency conversion strategy, and determine the current switching frequency and the current duty cycle.

7. The device according to claim 5, characterized in that The suppression module comprises: The second acquisition unit is used to acquire the pulse width modulation duty cycle and switching frequency of the switching device in the Buck circuit of the DC-DC converter of the power system before adjusting the switching frequency and duty cycle of the DC-DC converter of the power system.

8. The device according to claim 5, characterized in that The suppression module comprises: A first adjustment unit is used to determine a simultaneous turn-on moment or a simultaneous turn-off moment of the DC-DC converter and the three-phase inverter, generate the optimal switching frequency and the optimal duty cycle according to the simultaneous turn-on moment or the simultaneous turn-off moment, and adjust the switching frequency and the duty cycle of the DC-DC converter of the power supply system so that the two stagger the simultaneous turn-on moment or the simultaneous turn-off moment; Alternatively, a second adjustment unit is used to determine the simultaneous turn-on moment or the simultaneous turn-off moment of the DC-DC converter and the three-phase inverter, generate the optimal switching frequency and the optimal duty cycle according to the simultaneous turn-on moment or the simultaneous turn-off moment, and adjust the switching frequency and the duty cycle of the DC-DC converter of the power supply system so that the DC-DC converter of the power supply system performs the opposite action at the simultaneous turn-on moment or the simultaneous turn-off moment.

9. A vehicle, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the vehicle bus ripple suppression method as described in any one of claims 1 to 4.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the vehicle bus ripple suppression method as described in any one of claims 1 to 4.

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