Single-resistor sampling PWM (Pulse Width Modulation) driving method

Abstract

The invention discloses a single-resistor sampling PWM (Pulse Width Modulation) driving method. The single-resistor sampling PWM driving method comprises the steps that a single resistor samples three-phase current of a motor and transmits the three-phase current to a microcontroller; the microcontroller processes the three-phase current to obtain an alpha-axis voltage and a beta-axis voltage, and the alpha-axis voltage and the beta-axis voltage are subjected to space vector pulse width modulation processing to obtain a three-phase duty ratio and transmit the three-phase duty ratio to the PWM driving module; the PWM driving module performs phase shift processing on the received three-phase duty ratio, fixes a phase shift opening sequence, outputs a three-phase upper bridge opening moment and a three-phase upper bridge closing moment, and transmits the three-phase upper bridge opening moment and the three-phase upper bridge closing moment to the driving chip module; and the driving chip module controls the motor by controlling the three-phase bridge power tube. According to the invention, the phase shift opening sequence of the three-phase upper bridge is fixed, so that the noise generated by low-speed sector switching in the conventional single-resistor sampling is reduced.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of power electronic control technology, and in particular to a single resistor sampling PWM driving method. Background Art

[0002] At present, sensorless control based on brushless motors is applied to more and more occasions, and the application is more and more sensitive to cost. Therefore, the current mainstream basically adopts single resistor plus sensorless control. When the single resistor is at low modulation ratio and sector transition, there will be a non-sampling area, and the PWM needs to be phase-shifted. According to the normal phase shifting method, three-phase current can be collected, but there will be noise in the low-speed sector. On the other hand, the current sampling is far away from the starting point of the interrupt operation, and there will be a long sampling delay, which will eventually lead to deviations in the estimated position. Summary of the invention

[0003] The present invention provides a single resistor sampling PWM driving method, which fixes the phase shift opening sequence of the three-phase upper bridge, thereby reducing the noise generated by the low-speed switching of sectors in the previous single resistor sampling.

[0004] According to one aspect of the present invention, a single resistor sampling PWM driving method is provided, and the single resistor sampling PWM driving method comprises:

[0005] A single resistor samples the three-phase current of the motor and transmits it to the microcontroller;

[0006] The microcontroller processes the three-phase current to obtain an alpha axis voltage and a beta axis voltage, and the alpha axis voltage and the beta axis voltage are processed by space vector pulse width modulation to obtain a three-phase duty ratio and transmitted to a PWM drive module;

[0007] The PWM driving module performs phase shift processing on the received three-phase duty cycle and fixes the phase shift opening sequence, outputs the opening and closing time of the three-phase upper bridge and transmits it to the driving chip module;

[0008] The driving chip module controls the motor by controlling the three-phase bridge power tube.

[0009] Optionally, the single resistor sampling the three-phase current of the motor and transmitting it to the microcontroller includes:

[0010] The single resistor collects the current of the fixed phase of the motor through a fixed time delay and a fixed sampling position.

[0011] Optionally, the PWM driving module performs phase shift processing on the received three-phase duty cycle and fixes the phase shift opening sequence, outputs the three-phase upper bridge opening time and closing time and transmits them to the driving chip module, including:

[0012] The three-phase duty cycle is received and centrally symmetrically generated, and after PWM phase shift, the U-phase upper bridge opening time, the U-phase upper bridge closing time, the V-phase upper bridge opening time, the V-phase upper bridge closing time, the W-phase upper bridge opening time and the W-phase upper bridge closing time are output to the drive chip module.

[0013] Optionally, the expression for the U-phase upper bridge shut-off time is:

[0014] DutyU down =T PWM ;

[0015] The expression of the V-phase upper bridge shut-off time is:

[0016] DutyV down =(T PWM -T Sample );

[0017] The expression of the W phase upper bridge shut-off time is:

[0018] DutyW down =(T PWM -2*T Sample );

[0019] Among them, DutyU down is the U-phase upper bridge shut-off moment, DutyV down DutyW is the V phase upper bridge shut-off moment. down is the W phase upper bridge shut-off time, T PWM is the switching period, T Sample is the minimum window sampling time.

[0020] Optionally, the three-phase upper bridge opening time is calculated according to the three-phase duty cycle;

[0021] The expression of the U-phase upper bridge opening time is:

[0022] DutyU rise =(1-DutyU)*T PWM ;

[0023] The expression of the V-phase upper bridge opening time is:

[0024] DutyV rise =(1-DutyV-T Sample )*T PWM ;

[0025] The expression of the W phase upper bridge opening time is:

[0026] DutyW rise =(1-DutyW-2*TSample )*T PWM ;

[0027] Among them, DutyU rise The opening time of the U-phase bridge, DutyV rise The opening time of the V-phase bridge, DutyW rise is the W phase upper bridge opening time, DutyU is the U phase duty cycle, DutyV is the V phase duty cycle, DutyW is the W phase duty cycle, T PWM is the switching period, T Sample is the minimum window sampling time.

[0028] Optionally, the microcontroller processes the three-phase current to obtain an alpha axis voltage and a beta axis voltage, comprising:

[0029] The microcontroller processes the three-phase current through magnetic field oriented control and position sensorless control to obtain alpha axis voltage and beta axis voltage.

[0030] Optionally, the magnetic field oriented control comprises:

[0031] The three-phase current is transformed by Clark and Park to obtain dq axis currents, and the dq axis currents are controlled by a current loop PI and transformed by inverse Park to obtain alpha axis voltage and beta axis voltage.

[0032] Optionally, the position sensorless control includes: obtaining an estimated rotor position and angular velocity of the motor based on the input three-phase current, the alpha-axis voltage and the beta-axis voltage.

[0033] According to another aspect of the present invention, there is provided an electronic device, the electronic device comprising:

[0034] one or more processors;

[0035] A memory for storing one or more programs;

[0036] When the one or more programs are executed by the one or more processors, the one or more processors implement the single-resistance sampling PWM driving method as described in any embodiment of the present invention.

[0037] According to another aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the single-resistance sampling PWM driving method as described in any embodiment of the present invention is implemented.

[0038] The technical solution of the embodiment of the present invention provides a single resistor sampling PWM driving method, which includes: a single resistor samples the three-phase current of the motor and transmits it to a microcontroller; the microcontroller processes the three-phase current to obtain the alpha axis voltage and the beta axis voltage, and the alpha axis voltage and the beta axis voltage are processed by space vector pulse width modulation to obtain the three-phase duty ratio and transmitted to the PWM driving module; the PWM driving module performs phase shift processing on the received three-phase duty ratio and fixes the phase shift opening sequence of the three-phase upper bridge, outputs the opening time and the closing time of the three-phase upper bridge and transmits it to the driving chip module; the driving chip module controls the motor by controlling the three-phase bridge power tube. The phase shift opening sequence is fixed by the PWM driving module, thereby reducing the noise generated by the previous single resistor sampling when switching sectors at low speed. The present invention solves the problem that the existing single resistor sampling PWM driving method has a non-sampling area when the modulation ratio is low and the sector transition occurs, and the PWM needs to be phase shifted, but according to the normal phase shift method, the three-phase current can be collected, but there will be noise in the low-speed sector.

[0039] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0041] Figure 1 is a flow chart of a single resistor sampling PWM driving method provided according to an embodiment of the present invention;

[0042] Figure 2 A non-inductive control block diagram of single resistor sampling provided according to an embodiment of the present invention;

[0043] Figure 3 is a schematic diagram of a PWM phase shift provided according to an embodiment of the present invention;

[0044] Figure 4 It is a timing diagram of executing a single resistor sampling PWM drive control algorithm provided according to an embodiment of the present invention;

[0045] Figure 5 It is a schematic diagram of the structure of an electronic device provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0046] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0047] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0048] Figure 1 is a flowchart of a single resistor sampling PWM driving method provided according to an embodiment of the present invention, referring to Figure 1 The embodiment of the present invention provides a single resistor sampling PWM driving method, and the single resistor sampling PWM driving method includes:

[0049] S110, a single resistor samples the three-phase current of the motor and transmits it to the microcontroller.

[0050] S120, the microcontroller processes the three-phase current to obtain the alpha axis voltage and the beta axis voltage, and the alpha axis voltage and the beta axis voltage are processed by space vector pulse width modulation to obtain the three-phase duty ratio and transmitted to the PWM drive module.

[0051] S130, the PWM driving module performs phase shift processing on the received three-phase duty cycle and fixes the phase shift opening sequence, outputs the three-phase upper bridge opening time and closing time and transmits them to the driving chip module.

[0052] S140, the driver chip module controls the motor by controlling the three-phase bridge power tube.

[0053] Specifically, Figure 2 is a non-inductive control block diagram of a single resistor sampling according to an embodiment of the present invention, referring to Figure 2The microcontroller performs field-oriented control, position sensorless control and position sensorless control calculation on the three-phase current of the single-resistance motor to obtain the alpha axis voltage U alpha and beta axis voltage U beta . Alpha axis voltage U alpha and beta axis voltage U beta The three-phase duty ratios DutyU, DutyV and DutyW are obtained by space vector pulse width modulation (SVPWM) processing, and the three-phase duty ratios DutyU, DutyV and DutyW are transmitted to the PWM drive module. The PWM drive module performs phase shift processing on the three-phase duty ratios and fixes the phase shift opening sequence, and opens them in the order of U phase, W phase and V phase. The PWM drive module outputs the opening and closing time of the three-phase upper bridge to the drive chip module, and the drive chip module controls the motor by controlling the three-phase bridge power tube.

[0054] The technical solution of the embodiment of the present invention provides a single resistor sampling PWM driving method, which includes: a single resistor samples the three-phase current of the motor and transmits it to a microcontroller; the microcontroller processes the three-phase current to obtain the alpha axis voltage and the beta axis voltage, and the alpha axis voltage and the beta axis voltage are processed by space vector pulse width modulation to obtain the three-phase duty ratio and transmitted to the PWM driving module; the PWM driving module performs phase shift processing on the received three-phase duty ratio and fixes the phase shift opening sequence of the three-phase upper bridge, outputs the opening time and the closing time of the three-phase upper bridge and transmits it to the driving chip module; the driving chip module controls the motor by controlling the three-phase bridge power tube. The phase shift opening sequence is fixed by the PWM driving module, thereby reducing the noise generated by the previous single resistor sampling when switching sectors at low speed. The present invention solves the problem that the existing single resistor sampling PWM driving method has a non-sampling area when the modulation ratio is low and the sector transition occurs, and the PWM needs to be phase shifted, but according to the normal phase shift method, the three-phase current can be collected, but there will be noise in the low-speed sector.

[0055] Optionally, the single resistor sampling the three-phase current of the motor and transmitting it to the microcontroller includes:

[0056] A single resistor collects the current of a fixed phase of the motor through a fixed time delay and a fixed sampling position.

[0057] Specifically, for single resistor sampling applications, the PWM drive method implements a fixed delay and a fixed sampling position to collect the current of a fixed phase. On the one hand, it saves the steps of current calculation based on sectors and reduces the overall software load rate; on the other hand, it reduces the delay from sampling to interrupt operation and reduces the position error caused by sampling delay.

[0058] Optionally, the PWM driving module performs phase shift processing on the received three-phase duty cycle and fixes the phase shift opening sequence, outputs the three-phase upper bridge opening time and closing time and transmits them to the driving chip module, including:

[0059] Receive the three-phase duty cycle and perform center-symmetrical wave generation, and after PWM phase shift, output the U-phase upper bridge opening time, U-phase upper bridge closing time, V-phase upper bridge opening time, V-phase upper bridge closing time, W-phase upper bridge opening time and W-phase upper bridge closing time to the driver chip module.

[0060] Optionally, the expression for the U-phase upper bridge shut-off time is:

[0061] DutyU down =T PWM ;

[0062] The expression of the V phase upper bridge shut-off time is:

[0063] DutyV down =(T PWM -T Sample );

[0064] The expression of the W phase upper bridge shut-off time is:

[0065] DutyW down =(T PWM -2*T Sample );

[0066] Among them, DutyU down is the U-phase upper bridge shut-off moment, DutyV down DutyW is the V phase upper bridge shut-off moment. down is the W phase upper bridge shut-off time, T PWM is the switching period, T Sample is the minimum window sampling time.

[0067] Optionally, the three-phase upper bridge opening time is calculated according to the three-phase duty cycle;

[0068] The expression of the U-phase upper bridge opening time is:

[0069] DutyU rise =(1-DutyU)*T PWM ;

[0070] The expression of the V phase upper bridge opening time is:

[0071] DutyV rise =(1-DutyV-T Sample )*T PWM ;

[0072] The expression of the W phase upper bridge opening time is:

[0073] DutyW rise =(1-DutyW-2*T Sample )*T PWM ;

[0074] Among them, DutyU rise The opening time of the U-phase bridge, DutyV rise The opening time of the V-phase bridge, DutyW rise is the W phase upper bridge opening time, DutyU is the U phase duty cycle, DutyV is the V phase duty cycle, DutyW is the W phase duty cycle, T PWM is the switching period, T Sample is the minimum window sampling time.

[0075] Specifically, a normal PWM drive module (without PWM phase shift) accepts the duty ratios of the three phases U, V, and W, DutyU, DutyV, and DutyW, and generates the waves according to the central symmetry, with a switching period of T PWM The calculation formula for the opening and closing time of each phase upper bridge without PWM phase shift is as follows:

[0076]

[0077] Among them, DutyU rise′ DutyU is the U-phase upper bridge opening time without PWM phase shift, down′ DutyV is the U-phase upper bridge shutdown moment without PWM phase shift, rise′ DutyV is the V phase upper bridge opening time without PWM phase shift, down′ DutyW is the V-phase upper bridge shutdown moment without PWM phase shift, rise′ DutyW is the W phase upper bridge opening time without PWM phase shift, down′ is the W phase upper bridge opening time without PWM phase shift, DutyU is the U phase duty cycle, DutyV is the V phase duty cycle, DutyW is the W phase duty cycle, T PWM is the switching cycle.

[0078] Figure 3 is a schematic diagram of a PWM phase shift provided according to an embodiment of the present invention, with reference to Figure 3After PWM phase shift, the U phase upper bridge is turned off at the rightmost switching cycle T PWM , the V phase upper bridge is turned off at (T PWM -T Sample ), the W phase upper bridge is turned off at (T PWM -2*T Sample ). The three-phase upper bridge opening time is calculated according to the three-phase duty cycle.

[0079] T Sample is the minimum sampling window time, and two current samplings are performed between the two sampling window times. The two current sampling times are CS1 and CS2, and CS1 corresponds to the basic voltage vector 110 (SVPWM control has 8 voltage vectors, 000 means UVW upper bridge arm is turned off, 100 means upper bridge arm U is on and VW is off, and 110 means upper bridge arm UV is on and W is off. This and the phase shift Figure 3 CS1 and CS2 are corresponding), the collected bus current corresponds to -I w , CS2 corresponds to the basic voltage vector 100 (100 means that the upper bridge arm U is on and VW is off. In this state, the current collected by the bus sampling resistor is equivalent to the U phase current; similarly, 110 means that the upper bridge arm UV is on and W is off. In this state, the current collected by the bus sampling resistor is equivalent to the negative W phase current). The collected bus current corresponds to I u , V phase current is based on the three-phase current and I u +I v +I w =0 is calculated.

[0080] Optionally, the microcontroller processes the three-phase current to obtain the alpha axis voltage and the beta axis voltage including:

[0081] The microcontroller processes the three-phase current through field-oriented control and position sensorless control to obtain the alpha axis voltage U alpha and beta axis voltage U beta .

[0082] Optionally, the field oriented control comprises:

[0083] The three-phase current is transformed by Clark and Park to obtain the dq axis current, which is controlled by the current loop PI and transformed by inverse Park to obtain the alpha axis voltage U alpha and beta axis voltage U beta .

[0084] Optionally, the position sensorless control includes: based on the input three-phase current, alpha axis voltage U alpha and beta axis voltage U beta Get the estimated rotor position and angular velocity of the motor.

[0085] Specifically, Field Oriented Control (FOC), also known as vector control, can improve the efficiency, control stability and accuracy of the motor. It is widely used in motor drive systems and is currently one of the best methods for efficient control of brushless DC motors, permanent magnet synchronous motors and induction motors.

[0086] The whole process of FOC control is as follows: collect three-phase currents IA, IB, IC; perform Clark transformation on the three-phase currents IA, IB, IC to obtain currents Iα, Iβ in the two-phase stationary coordinate system; then perform Park transformation on Iα, Iβ to obtain currents Id, Iq in the rotating coordinate system; use Iα, Iβ and U alpha , U beta The observer is used to estimate the rotor speed Speed_est and angle θ; the error between the actual rotor speed Speed_est and the set target speed Speedr_ef is calculated; the error is thrown into the PI controller, and the actuator outputs Iq_ref; the error between Id, Iq and the set values ​​Id_ref, Iq_ref is calculated; the error is thrown into the PI controller, and the actuator outputs Ud, Uq respectively; Ud, Uq are subjected to inverse Park transformation to obtain U alpha , U beta ; Finally U alpha , U beta After SVPWM, it is transformed into voltages UA, UB, and UC acting on the three phases.

[0087] Figure 4 is a timing diagram of a single resistor sampling PWM drive control algorithm according to an embodiment of the present invention, referring to Figure 4 , the control algorithm execution sequence is as follows Figure 4 As shown, the phase current is sampled when the interrupt is about to end, and the PWM is updated at the starting point of the interrupt. At the same time, the FOC and senseless operations are performed after the phase current is read at the starting point of the interrupt, and PWM modulation is performed. The on-off moment of the upper bridge is updated to the bridge drive at the next starting point of the interrupt. The current sampling is followed by the FOC operation, which has basically no delay and will improve the position accuracy of the senseless operation estimation.

[0088] Figure 5A schematic diagram of the structure of an electronic device 1 that can be used to implement an embodiment of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0089] like Figure 5 As shown, the electronic device 1 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 1 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0090] A number of components in the electronic device 1 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 1 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0091] The processor 11 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, for example, a single resistor sampling PWM driving method.

[0092] In some embodiments, the single resistor sampling PWM driving method can be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed on the electronic device 1 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the single resistor sampling PWM driving method described above can be performed. Alternatively, in other embodiments, the processor 11 can be configured to execute the single resistor sampling PWM driving method in any other appropriate manner (for example, by means of firmware).

[0093] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0094] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0095] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in combination with an instruction execution system, device or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0096] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0097] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0098] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0099] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0100] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A single resistor sampling PWM driving method, characterized in that: include: A single resistor samples the three-phase current of the motor and transmits it to the microcontroller; The microcontroller processes the three-phase current to obtain an alpha axis voltage and a beta axis voltage, and the alpha axis voltage and the beta axis voltage are processed by space vector pulse width modulation to obtain a three-phase duty ratio and transmitted to a PWM drive module; The PWM driving module performs phase shift processing on the received three-phase duty cycle and fixes the phase shift opening sequence, outputs the opening and closing time of the three-phase upper bridge and transmits it to the driving chip module; The driving chip module controls the motor by controlling the three-phase bridge power tube.

2. The method according to claim 1, characterized in that The single resistor samples the three-phase current of the motor and transmits it to the microcontroller, comprising: The single resistor collects the current of the fixed phase of the motor through a fixed time delay and a fixed sampling position.

3. The method according to claim 1, characterized in that The PWM driving module performs phase shift processing on the received three-phase duty cycle and fixes the phase shift opening sequence, outputs the opening time and the closing time of the three-phase upper bridge and transmits them to the driving chip module, including: The three-phase duty cycle is received and centrally symmetrically generated, and after PWM phase shift, the U-phase upper bridge opening time, the U-phase upper bridge closing time, the V-phase upper bridge opening time, the V-phase upper bridge closing time, the W-phase upper bridge opening time and the W-phase upper bridge closing time are output to the drive chip module.

4. The method according to claim 3, characterized in that The expression of the U-phase upper bridge shut-off time is: DutyU down =T PWM ; The expression of the V-phase upper bridge shut-off time is: DutyV down =(T PWM -T Sample ); The expression of the W phase upper bridge shut-off time is: DutyW down =(T PWM -2*T Sample ); Among them, DutyU down is the U-phase upper bridge shut-off moment, DutyV down DutyW is the V phase upper bridge shut-off moment. down is the W phase upper bridge shut-off time, T PWM is the switching period, T Sample is the minimum window sampling time.

5. The method according to claim 3, characterized in that: The three-phase upper bridge opening time is calculated according to the three-phase duty cycle; The expression of the U-phase upper bridge opening time is: DutyU rise =(1-DutyU)*T PWM , The expression of the V-phase upper bridge opening time is: DutyV rise =(1-DutyV-T Sample )*T PWM ; The expression of the W phase upper bridge opening time is: DutyW rise =(1-DutyW-2*T Sample )*T PWM ; Among them, DutyU rise The opening time of the U-phase bridge, DutyV rise The opening time of the V-phase bridge, DutyW rise is the W phase upper bridge opening time, DutyU is the U phase duty cycle, DutyV is the V phase duty cycle, DutyW is the W phase duty cycle, T PWM is the switching period, T Sample is the minimum window sampling time.

6. The method according to claim 1, characterized in that The microcontroller processes the three-phase current to obtain the alpha axis voltage and the beta axis voltage, including: The microcontroller processes the three-phase current through magnetic field oriented control and position sensorless control to obtain alpha axis voltage and beta axis voltage.

7. The method according to claim 6, characterized in that The field oriented control comprises: The three-phase current is transformed by Clark and Park to obtain dq axis currents, and the dq axis currents are controlled by a current loop PI and transformed by inverse Park to obtain alpha axis voltage and beta axis voltage.

8. The method according to claim 6, characterized in that The position sensorless control includes obtaining an estimated rotor position and angular velocity of the motor based on the input three-phase currents, the alpha-axis voltage, and the beta-axis voltage.

9. An electronic device, characterized in that: include: one or more processors; A memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the single resistor sampling PWM driving method as described in claims 1-8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the single resistor sampling PWM driving method as described in claims 1-8 is implemented.

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