Method, device and medium for determining inverter voltage compensation

Abstract

The embodiment of the invention relates to a method and device for determining voltage compensation of a permanent magnet synchronous motor inverter and a medium. The method comprises the steps that a straight axis of a rotor rotating coordinate system of a permanent magnet synchronous motor is aligned to a reference axis in a three-phase coordinate system; inputting a plurality of voltages to the aligned permanent magnet synchronous motor to obtain corresponding three-phase current values; performing conversion processing on the obtained three-phase current to obtain a converted direct-axis current; fitting the relationship between the input voltage and the obtained corresponding direct-axis current in a first range in which the input voltage is less than half of the dead-zone voltage of the motor to obtain a first slope value, and fitting the relationship between the input voltage and the corresponding direct-axis current in a second range in which the dead-zone voltage of the motor is saturated to obtain a second slope value; and determining voltage compensation of the permanent magnet synchronous motor inverter based on the acquired first slope value and the second slope value.

Description

Technical Field

[0001] The present invention relates to the field of motor control technology, and more specifically, to a method, a device and a medium for determining voltage compensation of a permanent magnet synchronous motor inverter. Background Art

[0002] Motors are widely used devices that convert electrical energy into kinetic energy. Taking the permanent magnet synchronous motor (PMSM) as an example, it is widely used in modern industry due to its high power density, excellent energy efficiency and fast dynamic response. To drive the motor, a voltage source inverter (VSI) composed of power electronic devices such as insulated gate bipolar transistors (IGBTs) is usually used. When these power devices are switched, a dead time is usually inserted in the gate signal to avoid transistor short circuit. The insertion of dead time, coupled with other non-ideal characteristics such as finite switching time, parasitic capacitance and voltage drop, causes the inverter output voltage to deviate from the expected voltage reference command. This voltage error causes unnecessary harmonics in the motor phase current, which in turn causes ripples in the output torque, especially in the low current state. In sensorless control, the accuracy of angular position estimation is also reduced.

[0003] Over the years, various methods of determining voltage compensation have been developed to eliminate or mitigate the effects of voltage errors. In early studies, researchers compensated for voltage losses caused by dead time by directly adjusting the pulse time. Another common method is average voltage compensation, which can be further divided into current feedback and voltage feedback compensation. In recent years, more complex algorithms have been proposed for real-time identification or compensation of voltage losses.

[0004] Among the above methods, the current feedback compensation method is widely used in industrial applications. This method uses a mathematical model of voltage loss, in which the voltage error is a function of the phase current. In the motor current controller, the voltage command can be compensated based on the measured current. Specific voltage loss models include parametric models (such as specific mathematical functions) or non-parametric models (such as lookup tables).

[0005] Parametric models are easy to identify and implement, but their accuracy is constrained by the mathematical function chosen. For example, a simple symbolic function model only considers the polarity of the phase current, and the voltage command is therefore compensated by a fixed amount. On the other hand, non-parametric models are usually able to achieve accurate compensation, but they can be cumbersome to identify and require additional equipment. For example, the VSI error at different currents can be manually measured and stored in memory, and the lost voltage can be accurately compensated by looking up the data in the table during compensation.

[0006] However, existing methods require pre-measurement of the inverter dead time, turn-on delay and turn-off delay, and voltage loss under different currents. The measurement process is relatively cumbersome, requiring the transistor to be taken out separately for testing and requiring additional sensors to complete the measurement. Existing methods rely on functions to fit the voltage error, and the accuracy is limited by the selected function, and cannot be widely applied to different types of power tubes or inverters.

[0007] Therefore, a method is needed to determine the voltage compensation without measuring the inverter dead time. Summary of the invention

[0008] In response to the above problems, the present disclosure provides a method for determining the voltage compensation of a permanent magnet synchronous motor inverter, the method comprising aligning the direct axis of the rotor rotation coordinate system of the permanent magnet synchronous motor to the reference axis in the three-phase coordinate system; inputting multiple voltages to the aligned permanent magnet synchronous motor to obtain corresponding three-phase current values; performing transformation processing on the obtained three-phase current to obtain a transformed direct axis current; within a first range where the input voltage is less than half of the motor dead zone voltage, fitting the relationship between the input voltage and the corresponding direct axis current obtained to obtain a first slope value, and fitting the relationship between the input voltage and the corresponding direct axis current within a second range where the motor dead zone voltage is saturated to obtain a second slope value; and determining the voltage compensation within the entire range of the permanent magnet synchronous motor inverter based on the obtained first slope value and the second slope value.

[0009] In one embodiment, determining the voltage compensation of the permanent magnet synchronous motor inverter also includes: calculating the difference between the acquired first slope value and the second slope value, wherein the difference is the voltage compensation of the permanent magnet synchronous motor within the first range, and using the difference as the initial value of the voltage compensation within the second range.

[0010] In one embodiment, determining the voltage compensation of the permanent magnet synchronous motor inverter also includes: determining the motor type based on whether the permanent magnet synchronous motor has a position sensor; determining the corresponding electrical parameters of the permanent magnet synchronous motor based on the determined motor type; determining a motor state observer for observing the permanent magnet synchronous motor based on the determined initial value of the voltage compensation of the permanent magnet synchronous motor within the second range, the motor type and the corresponding electrical parameters; establishing a discrete prediction model of the permanent magnet synchronous motor using the determined motor state observer; and determining the voltage compensation of the permanent magnet synchronous motor within the second range based on the discrete prediction model.

[0011] In one embodiment, determining corresponding electrical parameters of the permanent magnet synchronous motor based on the determined motor type includes: determining an input voltage instruction, corresponding three-phase current values, a motor rotor angle, and a rotation speed of the permanent magnet synchronous motor based on the determined motor type.

[0012] In one embodiment, establishing a discrete prediction model for a permanent magnet synchronous motor includes: in response to the permanent magnet synchronous motor being an inductorless motor, establishing a flux observer based on a differential equation corresponding to the inductorless motor; changing the current based on a linear difference so as to update a voltage compensation value observed by the flux observer, thereby obtaining a discrete voltage compensation value corresponding to the linear difference; and establishing a discrete prediction model for the permanent magnet synchronous motor based on the linear difference and the corresponding discrete voltage compensation value obtained.

[0013] In one embodiment, establishing a discrete prediction model for a permanent magnet synchronous motor includes: in response to the permanent magnet synchronous motor being an inductive motor, establishing an extended state observer based on a differential equation corresponding to the inductive motor; changing the current based on a linear difference so as to update a voltage compensation value observed by the extended state observer, thereby obtaining a discrete voltage compensation value corresponding to the linear difference; and establishing a discrete prediction model for the permanent magnet synchronous motor based on the linear difference and the corresponding discrete voltage compensation value obtained.

[0014] In one embodiment, determining the voltage compensation of the permanent magnet synchronous motor within the second range includes: determining the voltage compensation corresponding to each phase current in the three-phase current based on a discrete prediction model; and performing a transformation on the determined voltage compensation corresponding to each phase current to obtain the voltage compensation of the permanent magnet synchronous motor within the second range corresponding to the direct axis and the quadrature axis of the rotor rotation coordinate system.

[0015] According to a second aspect of the present disclosure, a computing device is provided, comprising: at least one processor; and a memory communicatively connected to the at least one processor; 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 method of the first aspect of the present disclosure.

[0016] In a third aspect of the present disclosure, a non-transitory computer-readable storage medium storing computer instructions is provided, wherein the computer instructions are used to cause a computer to execute the method of the first aspect of the present disclosure.

[0017] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements.

[0019] Figure 1A schematic diagram of a system 100 for implementing a method for determining a voltage compensation of a permanent magnet synchronous motor inverter according to an embodiment of the present disclosure is shown.

[0020] Figure 2 A flow chart of a method 200 for determining a voltage compensation of a permanent magnet synchronous motor inverter according to an embodiment of the present disclosure is shown.

[0021] Figure 3 A schematic diagram of determining voltage compensation in a small current range of a permanent magnet synchronous motor inverter according to an embodiment of the present invention is shown.

[0022] Figure 4 A flow chart of a method 400 for determining a voltage compensation of a permanent magnet synchronous motor inverter according to an embodiment of the present disclosure is shown.

[0023] Figure 5 A schematic diagram of determining voltage compensation in a large current range of a permanent magnet synchronous motor inverter according to an embodiment of the present invention is shown.

[0024] Figure 6 A schematic block diagram of an example electronic device 600 is shown that may be used to implement embodiments of the present disclosure. DETAILED DESCRIPTION

[0025] The following is a description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, including various details of the embodiments of the present disclosure to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0026] As used herein, the term "including" and its variations mean open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "based at least in part on". The terms "an example embodiment" and "an embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0027] Figure 1 FIG. 1 is a schematic diagram of a system 100 for implementing a method for determining voltage compensation of a permanent magnet synchronous motor inverter according to an embodiment of the present disclosure. Figure 1As shown in FIG. 1 , the system 100 includes a computing device 110, a voltage compensation computing device 130, and a network 140. The computing device 110 and the voltage compensation computing device 130 can perform data exchange through the network 140 (eg, the Internet).

[0028] The voltage compensation calculation device 130, for example, can perform functions such as determining the voltage compensation of the motor dead zone. The voltage compensation calculation device 130 can also send the determined voltage compensation data to the computing device 110. The voltage compensation calculation device 130 can have one or more processing units, including dedicated processing units such as GPU, FPGA and ASIC, and general processing units such as CPU, for example but not limited to: desktop computers, laptop computers, netbook computers, tablet computers, web browsers, e-book readers, personal digital assistants (PDAs) and wearable computers (such as smart watches and activity tracker devices) that can perform Chinese data reading and modification.

[0029] Regarding the computing device 110, it is used, for example, to receive voltage compensation data from the voltage compensation computing device 130 via the network 140. The computing device 110 may have one or more processing units, including dedicated processing units such as GPUs, FPGAs, and ASICs, and general processing units such as CPUs. In addition, one or more virtual machines may also be running on each computing device 110. In some embodiments, the computing device 110 and the voltage compensation computing device 130 may be integrated together or may be separately arranged from each other. In some embodiments, the computing device 110, for example.

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with practical applications and with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of them.

[0031] Figure 2 1 is a flow chart of a method 200 for determining voltage compensation of a permanent magnet synchronous motor inverter according to an embodiment of the present disclosure. The method 200 may be performed as follows: Figure 1 The computing device 110 shown may also be executed in Figure 6 The method 200 is executed at the electronic device 600. It should be understood that the method 200 may further include additional blocks not shown and / or may omit the blocks shown, and the scope of the present disclosure is not limited in this respect.

[0032] This embodiment describes a method for determining a voltage compensation of a permanent magnet synchronous motor inverter.

[0033] In step 202, the computing device 110 may align the d-direct axis of the motor rotor rotating coordinate system to the reference axis in the three-phase coordinate system. Note that in the present invention, the direct axis refers to the d-axis in the motor dq coordinate system, and the quadrature axis refers to the q-axis in the motor dq coordinate system.

[0034] Specifically, the d-axis (rotor N-stage) of the motor rotor rotating coordinate system can be aligned to the a-axis (a-phase stator winding) of the fixed coordinate system, and the electrical angle is 0 at this time.

[0035] In step 204, the computing device 110 may inject multiple voltages into the aligned motor to obtain corresponding three-phase current values, such as a, b, and c axis voltages. For example, a series of monotonically increasing positive voltage commands may be injected into the aligned motor d axis, and the corresponding abc axis current values ​​i may be measured. abc .

[0036] In step 206, the computing device 110 may perform a transformation process on the acquired three-phase current to obtain a transformed direct-axis current. For example, the above current is subjected to a Park transformation process to obtain a transformed dq-axis current i dq =P(θ)i abc , where P(θ) is the Park transformation matrix

[0037] In step 208 , the computing device 110 may divide the voltage compensation into two ranges, a first range and a second range, wherein the first range may be understood as a small current range, and the second range may be understood as a large current range.

[0038] Within a first small current range where the voltage is less than half of the motor dead zone voltage, the relationship between the injected voltage and the corresponding direct-axis current is fit to obtain a first slope value, and within a second large current range where the motor dead zone voltage is saturated, the relationship between the injected voltage and the corresponding direct-axis current is fit to obtain a second slope value.

[0039] Figure 3 A schematic diagram of determining voltage compensation in a small current range of a permanent magnet synchronous motor inverter according to an embodiment of the present invention is shown.

[0040] like Figure 3 As shown, in the first range where the voltage is less than half of the motor dead zone voltage, that is, on line segment 2, the injected voltage u and the corresponding d-axis current i are fitted. d The relationship between the first slope value R s +R0. In the second largest current range of the motor dead zone voltage saturation, the injected voltage u and the corresponding d-axis current i are fitted. d The relationship between the two is used to obtain the second slope value Rs.

[0041] In step 210 , the computing device 110 may determine a voltage compensation within the entire range of the permanent magnet synchronous motor inverter based on the acquired first slope value and second slope value.

[0042] The computing device 110 may calculate the difference between the first slope value and the second slope value, where the difference is the voltage compensation of the motor within the first range and the initial value of the voltage compensation interval within the second range. s +R0 minus the second slope value R s The difference in R0 is obtained. In this region, e abc =R0i abc Therefore, the slope difference R0 is the voltage compensation of the motor in the first small current range, and R0 can be used as the initial value of the voltage compensation interval in the second large current range.

[0043] Figure 4 4 is a flow chart of a method 400 for determining voltage compensation of a permanent magnet synchronous motor inverter according to an embodiment of the present disclosure. The method 400 may be performed as follows: Figure 1 The computing device 110 shown may also be executed in Figure 6 The method 400 is executed at the electronic device 600 shown. It should be understood that the method 400 may further include additional blocks not shown and / or may omit the blocks shown, and the scope of the present disclosure is not limited in this respect.

[0044] Relative to method 200, method 400 is used to determine the voltage compensation for the second largest current range. At step 402, computing device 110 may determine the type of motor based on whether the motor has a position sensor. The type of motor is determined based on whether the motor has a position sensor. Motor types can be divided into sensored motors, such as motors with position sensors such as servo motors with encoders, and sensorless motors, such as motors without position sensors such as brushless DC motors (BLDC).

[0045] In step 404, the computing device 110 may determine corresponding electrical parameters of the motor based on the determined motor type. The electrical parameters to be determined include the motor's input voltage command, corresponding three-phase current values, the motor's rotor angle, and the speed.

[0046] Based on the determined motor type, the corresponding electrical parameters of the motor are determined. For example, a motor with a position sensor may have the following parameters: number of rotor pole pairs, stator resistance, d-axis and q-axis inductance, back-EMF constant, motor rotor angle, speed, etc. A motor without a position sensor may have the following parameters: number of rotor pole pairs, stator resistance, d-axis and q-axis inductance, back-EMF constant, motor rotor angle, speed, etc. The above parameters can be used for subsequent observer design.

[0047] In step 406 , an observer for observing the motor state is designed based on the determined initial value of the motor voltage compensation within the second range, the determined motor type, and the determined corresponding electrical parameters.

[0048] Based on the determined initial value of the voltage compensation of the motor in the second largest current range and the determined motor type and corresponding electrical parameters, an observer for observing the motor state is designed. For example, an extended state observer can be used to observe the state of an inductive motor or a flux observer can be used to observe the state of a non-inductive motor.

[0049] The following will specifically introduce how to design extended state observers for inductive motors and inductive motors respectively.

[0050] For example, for an inductive motor, a discrete prediction model of the motor is established based on the determined initial value of the voltage compensation within the second largest current range and the determined electrical parameters. For an inductive motor, a state expansion observer is established based on a differential equation corresponding to the inductive motor, the current is changed based on the linear difference, and the voltage compensation value observed by the state expansion observer is updated to obtain discrete voltage compensation values ​​corresponding to the linear difference of the current, and a discrete prediction model of the motor is established based on these values.

[0051] Figure 5 A schematic diagram of determining voltage compensation for a large current range of a permanent magnet synchronous motor inverter according to an embodiment of the present invention is shown. Specifically, the current range involved in the model is first divided into several linear functions, such as Figure 5 As shown, i1 is the small current range in method 200 ( Figure 2-6 ), e1 has been estimated from the previous part, that is, e abc The remaining current range is composed of i2, i3, ..., i k The remaining voltage loss models can be estimated step by step in an iterative manner. As described above, R0 can be used as the initial value of the voltage compensation interval in the second largest current range. Specifically, the initial value e1 of the second current range is equal to R0*i1.

[0052] Assume that the first k-1 segments The estimation has been completed, and the voltage loss of the kth segment needs to be estimated. First, let the motor run at a constant speed and adjust i d Make the phase current amplitude equal to i k The observer for the sensed case can be designed according to the following differential equation,

[0053]

[0054]

[0055] In formula (1), is the state variable of the observer; i d ,i q is the dq axis current, and the phase current i is obtained by measurement abc and the motor rotor angle θ; ψ q =L q i q is the q-axis magnetic flux, i q The speed ω and the motor rotor angle θ are measured by the encoder. is the error of the drive observer; g1 and g2 are the design parameters of the observer. The following describes how to calculate the estimated d-axis voltage

[0056] For formula (1), it is necessary to calculate the dq axis voltage error and Therefore, the voltage loss of the abc axis can be calculated using the table lookup method. Taking the a-axis current of three-phase electricity as an example, when the current is less than i1, the voltage loss is given by the linear model estimated in the previous part. n-1 ,i n Between and In particular, since is the value to be observed ( Figure 2-5 ),i k-1 to k The voltage loss of the segment will change as the observer is updated, and eventually Figure 5 The four parts in the above formula converge to the real voltage loss model. After the voltage losses of the abc axes in the three-phase power are calculated by the current, a discrete prediction model of the motor can be established. Based on the discrete prediction model, the dq axis voltage loss can be obtained through Park transformation.

[0057] The state expansion observer in this embodiment is only an example of a motor angle observer, and the present invention is not limited to using other algorithms to achieve the estimation of the voltage loss of the inductive motor. In the inductive state, any observer that estimates the voltage loss under a specific phase current can be used in the technical solution of the present invention.

[0058] For the inductorless motor, except for the constructed observer and the differential equation used to construct the observer, the rest of the method is similar to the inductor motor. A discrete prediction model of the motor is established based on the determined initial value of the voltage compensation within the second largest current range and the determined electrical parameters. For the inductorless motor, an observer is established based on the differential equation corresponding to the inductorless motor, the current is changed based on the linear difference, the voltage compensation value observed by the observer is updated to obtain discrete voltage compensation values ​​corresponding to the linear difference of the current, and a discrete prediction model of the motor is established based on these values.

[0059] For the inductive motor, the designed observer needs to observe the angle, speed and voltage loss at the same time. The differential equation is as follows:

[0060]

[0061]

[0062]

[0063]

[0064] In formula (2), is the flux, angle, speed and i of the observer k The state variable of voltage loss at the location; i = [i d ,i q ] T is the dq axis current; u=[u d ,u q ] T is the voltage command output by the controller; is the voltage loss of the dq axis (calculated in the same way as with inductive); is the error driving the observer; G1 is the 2×2 observer parameter matrix; g2, g3, g4 are the 2×1 observer parameter row vectors.

[0065] In step 408 , a voltage compensation of the motor within the second range is determined according to the discrete prediction model.

[0066] Specifically, based on the determined discrete prediction model, the voltage compensation e corresponding to each phase current a, b, and c in the three-phase current is determined. a 、e b and e c The voltage compensation corresponding to the direct axis and the quadrature axis of the motor rotation coordinate system within the second range is obtained by performing park transformation on the determined voltage compensation corresponding to each phase current.

[0067] Using the above technical solution, the process of estimating the non-parametric voltage loss model is iteratively performed according to the current from small to large. For example, the voltage loss of the phase current at a small current, such as 0-0.3 amperes, is first estimated by linear regression, and then the voltage loss at a large current, such as 0.3-0.4 amperes, is further estimated based on the previous estimated results and the extended state observer.

[0068] The present invention does not limit other observer methods to implement this solution. Those skilled in the art will appreciate that any observer can implement the process of iteratively estimating the driver voltage loss model from small to large currents. For example, by using an extended state observer, the value of the voltage loss under a specific phase current is estimated when the motor is running, without relying on a specific mathematical model.

[0069] The flux observer in this embodiment is only an example of a motor angle observer, and the present invention is not limited to using other algorithms to achieve angle or speed estimation. In a non-sensing state, any observer that simultaneously estimates the angle, speed, and dead zone loss of a specific phase current point of the motor can be used in the technical solution of the present invention.

[0070] Figure 6 Schematic block diagram of an example electronic device 600 that can be used to implement an embodiment of the present disclosure is shown. Figure 1 The computing device 110 shown can be implemented by an electronic device 600. As shown, the electronic device 600 includes a central processing unit (CPU) 601, which can perform various appropriate actions and processes according to computer program instructions stored in a read-only memory (ROM) 602 or computer program instructions loaded from a storage unit 608 to a random access memory (RAM) 603. In the random access memory 603, various programs and data required for the operation of the electronic device 600 can also be stored. The central processing unit 601, the read-only memory 602, and the random access memory 603 are connected to each other via a bus 604. An input / output (I / O) interface 605 is also connected to the bus 604.

[0071] Multiple components in the electronic device 600 are connected to the input / output interface 605, including: an input unit 606, such as a keyboard, a mouse, a microphone, etc.; an output unit 607, such as various types of displays, speakers, etc.; a storage unit 608, such as a disk, an optical disk, etc.; and a communication unit 609, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 609 allows the device 600 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0072] The various processes and processing described above, such as methods 200 and 400, may be performed by the central processing unit 601. For example, in some embodiments, the methods 200, 400, and 600 may be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as a storage unit 608. In some embodiments, part or all of the computer program may be loaded and / or installed on the device 600 via the read-only memory 602 and / or the communication unit 609. When the computer program is loaded into the random access memory 603 and executed by the central processing unit 601, one or more actions in the methods 200 and 400 described above may be performed.

[0073] The present disclosure relates to methods, apparatuses, systems, electronic devices, computer-readable storage media and / or computer program products. The computer program products may include computer-readable program instructions for executing various aspects of the present disclosure.

[0074] A computer-readable storage medium may be a tangible device that can hold and store instructions used by an instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples of computer-readable storage media (a non-exhaustive list) include: 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), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which instructions are stored, and any suitable combination of the foregoing. As used herein, a computer-readable storage medium is not to be interpreted as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0075] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network may include copper transmission cables, optical fiber transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge computing devices. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in a computer-readable storage medium in each computing / processing device.

[0076] The computer program instructions for performing the operation of the present disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages, such as Smalltalk, C++, etc., and conventional procedural programming languages, such as "C" language or similar programming languages. Computer-readable program instructions may be executed entirely on a user's computer, partially on a user's computer, as an independent software package, partially on a user's computer, partially on a remote computer, or completely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., using an Internet service provider to connect via the Internet). In some embodiments, an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), may be customized by utilizing the state information of the computer-readable program instructions, and the electronic circuit may execute the computer-readable program instructions, thereby realizing various aspects of the present disclosure.

[0077] Various aspects of the present disclosure are described herein with reference to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present disclosure. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer-readable program instructions.

[0078] These computer-readable program instructions can be provided to a processing unit of a general-purpose computer, a special-purpose computer, or other programmable data processing device, thereby producing a machine, so that when these instructions are executed by the processing unit of the computer or other programmable data processing device, a device that implements the functions / actions specified in one or more boxes in the flowchart and / or block diagram is generated. These computer-readable program instructions can also be stored in a computer-readable storage medium, and these instructions cause the computer, programmable data processing device, and / or other equipment to work in a specific manner, so that the computer-readable medium storing the instructions includes a manufactured product, which includes instructions for implementing various aspects of the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0079] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device so that a series of operating steps are performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to implement the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0080] The flow chart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to multiple embodiments of the present disclosure. In this regard, each square box in the flow chart or block diagram can represent a part of a module, program segment or instruction, and a part of a module, program segment or instruction includes one or more executable instructions for realizing the specified logical function. In some alternative implementations, the function marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two continuous square boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs the specified function or action, or can be implemented with a combination of special hardware and computer instructions.

[0081] Those skilled in the art should understand that the present invention is not limited to the above-mentioned embodiments, and the present invention can be implemented in many other forms without departing from its purpose and scope. Therefore, the examples and embodiments shown are regarded as illustrative rather than restrictive, and the present invention may cover various modifications and substitutions without departing from the spirit and scope of the present invention as defined in the appended claims.

Claims

1. A method for determining voltage compensation of a permanent magnet synchronous motor inverter, characterized in that: Aligning the direct axis of the rotor rotation coordinate system of the permanent magnet synchronous motor to the reference axis in the three-phase coordinate system; Inputting multiple voltages to the aligned permanent magnet synchronous motor to obtain corresponding three-phase current values; performing a transformation process on the acquired three-phase current to obtain a transformed direct-axis current; Fitting the relationship between the input voltage and the corresponding direct-axis current obtained within a first range where the input voltage is less than half of the motor dead zone voltage to obtain a first slope value, and fitting the relationship between the input voltage and the corresponding direct-axis current within a second range where the motor dead zone voltage is saturated to obtain a second slope value; as well as Based on the acquired first slope value and second slope value, a voltage compensation of the permanent magnet synchronous motor inverter within the entire range is determined.

2. The method according to claim 1, characterized in that Determining the voltage compensation of the permanent magnet synchronous motor inverter also includes: A difference between the acquired first slope value and the second slope value is calculated, where the difference is the voltage compensation of the permanent magnet synchronous motor within the first range, and the difference is used as an initial value of the voltage compensation within the second range.

3. The method according to claim 2, characterized in that Determining the voltage compensation of the permanent magnet synchronous motor inverter also includes: Determine the motor type based on whether the permanent magnet synchronous motor has a position sensor; Based on the determined motor type, determining corresponding electrical parameters of the permanent magnet synchronous motor; Determine a motor state observer for observing the permanent magnet synchronous motor based on the determined initial value of voltage compensation of the permanent magnet synchronous motor within the second range, the motor type, and corresponding electrical parameters; Using the determined motor state observer, a discrete prediction model of the permanent magnet synchronous motor is established; and According to the discrete prediction model, a voltage compensation of the permanent magnet synchronous motor within the second range is determined.

4. The method according to claim 3, characterized in that Based on the determined motor type, the corresponding electrical parameters of the permanent magnet synchronous motor are determined including: Based on the determined motor type, the input voltage command, corresponding three-phase current value, motor rotor angle, and speed of the permanent magnet synchronous motor are determined.

5. The method according to claim 4, characterized in that The discrete prediction model of permanent magnet synchronous motor is established including: In response to the permanent magnet synchronous motor being an inductorless motor, a flux observer is established based on a differential equation corresponding to the inductorless motor; Changing the current based on the linear difference so as to update the voltage compensation value observed by the flux observer, thereby obtaining a discrete voltage compensation value corresponding to the linear difference; and Based on the linear difference and the corresponding discrete voltage compensation value obtained, a discrete prediction model of the permanent magnet synchronous motor is established.

6. The method according to claim 4, characterized in that The discrete prediction model of permanent magnet synchronous motor is established including: In response to the permanent magnet synchronous motor being an inductive motor, an extended state observer is established based on a differential equation corresponding to the inductive motor; Changing the current based on the linear difference so as to update the voltage compensation value observed by the extended state observer, thereby obtaining a discrete voltage compensation value corresponding to the linear difference; and Based on the linear difference and the corresponding discrete voltage compensation value obtained, a discrete prediction model of the permanent magnet synchronous motor is established.

7. The method according to claim 3, characterized in that Determining the voltage compensation of the permanent magnet synchronous motor within the second range includes: Determining a voltage compensation corresponding to each phase current of the three-phase current based on a discrete prediction model; and Transformation is performed on the determined voltage compensation corresponding to each phase current to obtain voltage compensation corresponding to the direct axis and the quadrature axis of the rotor rotation coordinate system of the permanent magnet synchronous motor within the second range.

8. A computing device comprising: at least one processor; as well as a memory communicatively coupled to the at least one processor; The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 7.

9. A non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to cause the computer to execute the method of any one of claims 1 to 7.

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