A high-speed switching method in a permanent magnet synchronous motor speed sensorless control system

Abstract

The application relates to a control technology of a permanent magnet synchronous motor, and provides a high-speed switching method in a speed sensorless control system of the permanent magnet synchronous motor, which comprises the following steps: setting a switching frequency point and a switching frequency bandwidth of IF control and sliding film control; calculating a smooth switching transition coefficient according to the relationship between the actual operation frequency of the motor and the switching frequency point and the switching frequency bandwidth; determining a switching strategy according to the smooth switching transition coefficient, and making the switching process smooth and non-abrupt; wherein the switching process comprises switching from the IF control to the sliding film control and switching from the sliding film control to the IF control. The high-speed switching method in the speed sensorless control system of the permanent magnet synchronous motor not only considers the smooth switching from a low-speed stage to a medium-high-speed stage, but also considers the smooth switching from the medium-high-speed stage to the low-speed stage, the speed fluctuation is small in the switching process, meanwhile, the method can adapt to the change of a load and can effectively cope with various complex working conditions.

Description

Technical Field

[0001] This invention relates to control technology for permanent magnet synchronous motors, and in particular to a high-speed switching method in a sensorless control system for permanent magnet synchronous motors. Background Technology

[0002] A permanent magnet synchronous motor is a small-power synchronous motor that uses permanent magnets to establish an excitation magnetic field. It mainly consists of a stator, rotor, and end covers. The stator generates a rotating magnetic field, and the rotor is made of permanent magnet material. The excitation is provided by permanent magnets, which simplifies the motor structure, reduces processing and assembly costs, and eliminates the need for slip rings and brushes, which are prone to problems, thus improving the reliability of motor operation. Furthermore, since no excitation current is required, there is no excitation loss, which improves the efficiency and power density of the motor. Currently, it is widely used in industrial and agricultural production, transportation, national defense, commercial and household appliances, medical electrical equipment, and other fields.

[0003] In the sensorless control system of permanent magnet synchronous motor, since the back electromotive force of the motor is small at zero speed and low speed, the IF control method is used at low speed and the sliding diaphragm estimation method is used at medium and high speed. This technology ensures a stable transition between IF control and sliding diaphragm control in the application of sensorless algorithms.

[0004] Existing seamless switching methods are mainly divided into two types: one is a weighted coefficient correction method for rotor position angle, which gradually transitions the IF control angle to the sliding diaphragm estimated angle. This method does not consider the change in current amplitude, and there will be speed fluctuations greater than 70 r / min during the switching process. The other is a transition method based on the change in current amplitude, which uses the principle of torque-power angle self-balancing to gradually reduce the IF control current so that the IF control angle automatically adjusts to the sliding diaphragm angle. However, this method does not consider the load change situation, and the fixed current change mode during the switching process cannot adapt to complex actual working conditions. How to reduce the fluctuation during the switching process and how to achieve autonomous adjustment and adaptation when the load changes have important impacts on the overall performance of permanent magnet synchronous motors.

[0005] Therefore, overcoming the shortcomings of the existing technology is an urgent problem to be solved in this technical field. Summary of the Invention

[0006] This invention provides a solution to the technical problem of fluctuations during the switching process in existing seamless switching methods.

[0007] Furthermore, this invention provides a solution to the technical problem that existing contactless switching methods cannot adapt to complex actual working conditions during the switching process.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a high-speed switching method in a sensorless control system for a permanent magnet synchronous motor, the method comprising:

[0010] Set the switching frequency point f1 and switching frequency bandwidth f between IF control and sliding control. B ;

[0011] Based on the actual operating frequency f of the motor e With switching frequency point f1 and switching frequency bandwidth f B Based on the relationship, calculate the smooth switching transition coefficient σ;

[0012] Based on the smooth switching transition coefficient σ, determine the switching strategy to ensure a smooth switching process without abrupt changes;

[0013] The switching process includes switching from IF control to sliding control, and switching from sliding control to IF control.

[0014] Preferably, the step of adjusting the motor's actual operating frequency f e With switching frequency point f1 and switching frequency bandwidth f B The relationship between the two factors is used to calculate the smooth switching transition coefficient σ. Methods include:

[0015]

[0016] Preferably, the method for switching from IF control to slewing control includes:

[0017] When the actual operating frequency of the motor is f e When the value is increased to f1, calculate the difference Δθ between the angle controlled by IF and the angle estimated by the sliding diaphragm at the switching point. L-H ;

[0018] Assign the angle controlled by IF to the angle estimated by the diaphragm, and assign the current controlled by IF to the integral output of the speed loop in the diaphragm control system;

[0019] When the actual operating frequency of the motor is f e Increase to f1 to f1+f B During this period, the angle of the sliding diaphragm control is compensated, and the current is given by the speed loop output.

[0020] In the process of compensating for the angle of the sliding diaphragm control, the speed loop can synchronously adjust the output torque current setpoint.

[0021] Preferably, the angle difference Δθ between the IF control angle and the slicker membrane estimated at the calculation switching point is... L-H The methods specifically include:

[0022] Δθ L-H =θ1-θ2

[0023] Where θ1 is the angle controlled by IF during switching, and θ2 is the angle estimated by the sliding diaphragm.

[0024] Preferably, the method of assigning the angle controlled by IF to the angle estimated by the diaphragm and assigning the current controlled by IF to the integral output of the speed loop in the diaphragm control system specifically includes:

[0025] θ SMO =θ1

[0026] SpeedPI.Integral_out = I base

[0027] Where, θ SMO The angle estimated by the diaphragm; SpeedPI.Integral_out is the integral output of the diaphragm control speed loop during switching; I base This is the current controlled by IF.

[0028] Preferably, the compensation for the sliding diaphragm control angle is given by the current output from the speed loop, and the method specifically includes:

[0029] θ HFd =θ SMO +σ*Δθ L-H

[0030] I HFq =SpeedPI.out

[0031] Where, θ HFd To control the rotor position angle using a sliding diaphragm, I HFq The torque current is given by the sliding diaphragm control, and SpeedPI.out is the output of the sliding diaphragm control speed loop.

[0032] Preferably, the method for switching from synovial control to IF control includes:

[0033] When the actual operating frequency of the motor is f e Reduce to f1+f B At that time, calculate the current difference ΔI between the speed loop output and the IF control in the sliding diaphragm control system. H-L and angle difference Δθ H-L ;

[0034] Assign the angle controlled by the diaphragm to the angle estimated by the IF, and assign the speed loop output in the diaphragm control system to the current controlled by the IF.

[0035] When the actual operating frequency of the motor is f e Reduce to f1+f BWhen the current and angle controlled by IF are between f1 and f2, a compensation transition is performed.

[0036] Preferably, the current difference ΔI between the speed loop output and the IF control in the calculation of the sliding diaphragm control system is... H-L and angle difference Δθ H-L The methods specifically include:

[0037] ΔI H-L =I base -SpeedPI.out

[0038]

[0039] Among them, I base This is the current controlled by IF.

[0040] Preferably, the method of assigning the angle controlled by the diaphragm to the angle estimated by the IF, and assigning the speed loop output of the diaphragm control system to the current controlled by the IF, specifically includes:

[0041] θ IF =θ4

[0042] I3 = SpeedPI.out

[0043] Where, θ IF θ4 is the angle controlled by IF during switching, θ3 is the angle estimated by the sliding diaphragm during switching, and I3 is the current controlled by IF during switching.

[0044] Preferably, the method for compensating the current and angle controlled by IF specifically includes:

[0045] I LFq =I3+σ*ΔI H-L

[0046] θ LFd =θ IF +σ*Δθ H-L +Δθ e

[0047] Among them, I LFq For the current controlled by IF, θ LFd For IF to control the rotor position angle, Δθ e This is the step angle corresponding to the IF control speed.

[0048] In a second aspect, the present invention provides an electronic device, the electronic device comprising:

[0049] At least one processor; and,

[0050] A memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the processor for performing the high-speed switching method in a sensorless control system for a permanent magnet synchronous motor as described in the first aspect.

[0051] Thirdly, the present invention provides a computer storage medium on which a computer program is stored, wherein when the computer program is executed by a processor, the computer program implements the steps of the high-speed switching method in a sensorless control system for a permanent magnet synchronous motor as described in the first aspect.

[0052] In view of the shortcomings of the prior art, the beneficial effects that the present invention can achieve are as follows:

[0053] This invention provides a high-speed switching method in a sensorless control system for a permanent magnet synchronous motor. By calculating the difference in current and angle between IF control and sliding diaphragm control before switching, the method first switches to the control method to be used during switching. Then, within the switching frequency band, the angle and current of the control are compensated for and transitioned, so that there are no sudden changes in the current amplitude and angle throughout the process, ensuring the smoothness of the speed during the switching process.

[0054] Furthermore, the present invention provides a high-speed switching method in a sensorless control system for permanent magnet synchronous motors. When the IF switches to sliding diaphragm control, the speed loop in the sliding diaphragm control system can adjust in real time according to load changes, effectively coping with various working conditions.

[0055] Overall, the high-speed switching method in a sensorless control system for a permanent magnet synchronous motor provided by this invention not only considers the smooth switching from low-speed to medium-high-speed stages, but also the smooth switching from medium-high-speed stages to low-speed stages. During the switching process, the speed fluctuation is small, and it can also adapt to load changes, effectively coping with various complex working conditions. Attached Figure Description

[0056] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0057] Figure 1 This is a flowchart illustrating a high-speed switching method in a sensorless control system for a permanent magnet synchronous motor provided in an embodiment of the present invention.

[0058] Figure 2This is a flowchart illustrating a high-speed switching method in a sensorless control system for a permanent magnet synchronous motor provided in an embodiment of the present invention.

[0059] Figure 3 This is a flowchart illustrating a high-speed switching method in a sensorless control system for a permanent magnet synchronous motor provided in an embodiment of the present invention.

[0060] Figure 4 This is a schematic diagram of the structure of a high-speed switching electronic device in a sensorless control system for a permanent magnet synchronous motor provided in an embodiment of the present invention;

[0061] Figure 5 This is a schematic diagram of the structure of a high-speed switching computer storage medium in a sensorless control system for a permanent magnet synchronous motor provided in an embodiment of the present invention. Detailed Implementation

[0062] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. In addition, the technical features of the various embodiments or individual embodiments provided by the present invention can be arbitrarily combined with each other to form feasible technical solutions. Such combinations are not constrained by the order of steps and / or structural composition patterns, but must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0063] To address the technical problem of fluctuations during switching in existing sensorless switching methods, and to solve the problem that the current variation patterns in existing sensorless switching methods cannot adapt to complex actual operating conditions during switching, this embodiment provides a high-speed switching method in a sensorless control system for a permanent magnet synchronous motor, such as... Figure 1 The diagram shown is a flowchart illustrating a high-speed switching method in a sensorless control system for a permanent magnet synchronous motor according to an embodiment of the present invention. The method includes:

[0064] S100, set the switching frequency point f1 and switching frequency bandwidth f between IF control and sliding control. B .

[0065] In this step, the switching frequency point f1 and the switching frequency bandwidth f between the IF control and the sliding diaphragm control are... BFor pre-setting, in actual setting, as a preferred implementation method, it can be optimally determined by combining the results of detection or experimentation. Here, the switching frequency point f1 between IF control and sliding diaphragm control serves as one of the switching thresholds, and the switching frequency bandwidth f between IF control and sliding diaphragm control is... B It is a frequency band point above the switching frequency point f1 between the IF control and the sliding control, that is, from f1 to f B There is a transitional interval in the middle.

[0066] S200, based on the actual operating frequency f of the motor e With switching frequency point f1 and switching frequency bandwidth f B Based on the relationship, calculate the smooth switching transition coefficient σ.

[0067] In this step, the actual operating frequency f of the motor e The frequency f is the real-time operating frequency of the permanent magnet synchronous motor. The frequency range specified for different manufacturers and models of permanent magnet synchronous motors varies slightly. Typically, the actual operating frequency f of the motor is... e The range is between 0-200Hz.

[0068] In specific implementation, the step of determining the actual operating frequency f of the motor is... e With switching frequency point f1 and switching frequency bandwidth f B Based on the relationship, the smooth switching transition coefficient σ is calculated. As a preferred implementation method, the method includes:

[0069]

[0070] Using the above methods, the smooth switching transition coefficient σ was established with respect to the actual operating frequency f of the motor. e With switching frequency point f1 and switching frequency bandwidth f B The relationship is a piecewise function, where the switching frequency point f1 is the switching threshold of the permanent magnet synchronous motor during the switching process from low speed to medium and high speed. Simultaneously, the switching frequency point f1+f B This refers to the switching threshold for a permanent magnet synchronous motor when switching from medium-high speed to low speed.

[0071] S300, based on the smooth switching transition coefficient σ, determines the switching strategy to ensure a smooth switching process without abrupt changes; wherein, the switching process includes switching from IF control to sliding control, and switching from sliding control to IF control.

[0072] In this step, to ensure a smooth and abrupt transition of the permanent magnet synchronous motor from low speed to medium-high speed, the switch from IF control to sliding diaphragm control is as follows: Figure 2 As shown, the method includes:

[0073] S311, when the actual operating frequency of the motor is f e When the value is increased to f1, calculate the difference Δθ between the angle controlled by IF and the angle estimated by the sliding diaphragm at the switching point. L-H .

[0074] When the actual operating frequency f of the motor e When increased to f1, that is, during the switching process, the actual operating frequency f e This is equal to the moment when the frequency is switched, f1.

[0075] In practice, the difference Δθ between the angle controlled by the IF at the calculation switching point and the angle estimated by the sliding diaphragm is... L-H The methods specifically include:

[0076] Δθ L-H =θ1-θ2

[0077] Where θ1 is the angle controlled by IF during switching, and θ2 is the angle estimated by the sliding diaphragm.

[0078] S312 assigns the angle controlled by IF to the angle estimated by the diaphragm, and assigns the current controlled by IF to the integral output of the speed loop in the diaphragm control system.

[0079] In the above assignment process, the main purpose of assigning the angle controlled by IF to the angle estimated by the diaphragm is to reduce the angle difference caused by the switching process in advance. The main purpose of assigning the current controlled by IF to the integral output of the speed loop in the diaphragm control system is to reduce the current difference caused by the switching process in advance.

[0080] In specific implementation, the method of assigning the angle controlled by IF to the angle estimated by the sliding diaphragm and assigning the current controlled by IF to the integral output of the speed loop in the sliding diaphragm control system includes:

[0081] θ SMO =θ1

[0082] SpeedPI.Integral_out = I base

[0083] Where, θ SMO The angle estimated by the diaphragm; SpeedPI.Integral_out is the integral output of the diaphragm control speed loop during switching; I base This is the current controlled by IF.

[0084] S313, when the actual operating frequency of the motor is f e Increase to f1 to f1+f BDuring this process, the angle of the sliding diaphragm control is compensated, and the current is given by the speed loop output. In particular, during the compensation of the sliding diaphragm control angle, the speed loop can synchronously adjust the output torque current.

[0085] In this step, based on the application of the PI adaptive controller method, the speed information of the permanent magnet synchronous motor is obtained through the PI adaptive controller, and then the output torque current is adjusted synchronously through the speed loop. Regardless of whether the permanent magnet synchronous motor is under no-load or full-load conditions, it can achieve self-adaptation.

[0086] In specific implementation, the compensation for the sliding diaphragm control angle is given by the current output from the speed loop, and the method specifically includes:

[0087] θ HFd =θ SMO +σ*Δθ L-H

[0088] I HFq =SpeedPI.out

[0089] Where, θ HFd To control the rotor position angle using a sliding diaphragm, I HFq The torque current is given by the sliding diaphragm control, and SpeedPI.out is the output of the sliding diaphragm control speed loop.

[0090] The above steps S311-S313 constitute the entire process of switching from IF control to sliding diaphragm control, which corresponds to the process of a permanent magnet synchronous motor switching from low speed to medium-high speed. The underlying principle for this switch is as follows:

[0091] First, the virtual angle controlled by IF is given to the sliding diaphragm control angle. At the same time, the current controlled by IF is given to the integral output of the sliding diaphragm control speed loop. This ensures that there is no current or angle difference at the moment when IF control switches to sliding diaphragm control. Then, the angle is gradually compensated to the real angle of the sliding diaphragm within the switching frequency bandwidth, thereby achieving a smooth and abrupt transition from low speed to medium and high speed.

[0092] Furthermore, during the angle adjustment process, the current is adjusted in real time by the speed loop PI, and the adjustment process can cope with load changes, thus effectively dealing with various complex actual working conditions.

[0093] In this step, to ensure a smooth and abrupt transition from medium-high speed to low speed in the permanent magnet synchronous motor, the switch from sliding diaphragm control to IF control is as follows: Figure 3 As shown, the method includes:

[0094] S321, when the actual operating frequency of the motor is f e Reduce to f1+f BAt that time, calculate the current difference ΔI between the speed loop output and the IF control in the sliding diaphragm control system. H-L and angle difference Δθ H-L .

[0095] When the actual operating frequency f of the motor e Reduce to f1+f B At that time, that is, during the switching process, the actual operating frequency f e Equal to the frequency switching point f1+f B This moment in time.

[0096] In specific implementation, the calculation of the current difference ΔI between the speed loop output and the IF control in the sliding diaphragm control system is described. H-L and angle difference Δθ H-L The methods specifically include:

[0097] ΔI H-L =I base -SpeedPI.out

[0098]

[0099] Among them, I base This is the current controlled by IF.

[0100] S322 assigns the angle controlled by the diaphragm to the angle estimated by the IF, and assigns the speed loop output of the diaphragm control system to the current controlled by the IF.

[0101] Similarly, the purpose of assigning the angle controlled by the diaphragm to the angle estimated by the IF is to reduce the angle difference caused by the switching process in advance, and the purpose of assigning the speed loop output of the diaphragm control system to the current controlled by the IF is to reduce the current difference caused by the switching process in advance.

[0102] In specific implementation, the method of assigning the angle controlled by the sliding diaphragm to the angle estimated by the IF, and assigning the speed loop output of the sliding diaphragm control system to the current controlled by the IF, specifically includes:

[0103] θ IF =θ4

[0104] I3 = SpeedPI.out

[0105] Where, θ IF θ4 is the angle controlled by IF during switching, θ3 is the angle estimated by the sliding diaphragm during switching, and I3 is the current controlled by IF during switching.

[0106] S323, when the actual operating frequency of the motor is f e Reduce to f1+f B When the current and angle controlled by IF are between f1 and f2, a compensation transition is performed.

[0107] In specific implementation, the method for compensating the current and angle controlled by IF includes:

[0108] I LFq =I3+σ*ΔI H-L

[0109] θ LFd =θ IF +σ*Δθ H-L +Δθ e

[0110] Among them, I LFq For the current controlled by IF, θ LFd For IF to control the rotor position angle, Δθ e This is the step angle corresponding to the IF control speed.

[0111] Steps S321-S323 above describe the entire process of switching from sliding diaphragm control to IF control, which corresponds to the process of a permanent magnet synchronous motor switching from medium-high speed to low speed. The underlying principle for this switch is as follows:

[0112] First, the actual angle of the sliding diaphragm control is given to the angle of the IF control. At the same time, the speed loop output current of the sliding diaphragm control is given to the current of the IF control. This ensures that there is no current or angle difference at the moment of switching from the sliding diaphragm control to the IF control. Then, within the switching frequency bandwidth, the current is gradually transitioned to the set current of the IF control. As the current increases, the angle is adjusted in advance to ensure a smooth transition of current and angle during the switching process, thereby achieving a smooth and abrupt transition from medium-high speed to low speed.

[0113] Correspondingly, under the same overall technical concept, such as Figure 4 The diagram shown is a structural schematic of a high-speed switching electronic device in a sensorless control system for a permanent magnet synchronous motor provided in an embodiment of the present invention. The electronic device includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the processor to perform a high-speed switching method in a sensorless control system for a permanent magnet synchronous motor in the above embodiment.

[0114] Correspondingly, under the same overall technical concept, such as Figure 5The diagram shown is a structural schematic of a high-speed switching computer storage medium in a sensorless control system for a permanent magnet synchronous motor provided by an embodiment of the present invention. The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of a high-speed switching method in a sensorless control system for a permanent magnet synchronous motor as described above.

[0115] In summary, the high-speed switching method in a sensorless control system for a permanent magnet synchronous motor provided by this invention not only considers the smooth switching from low-speed to medium-high-speed stages, but also the smooth switching from medium-high-speed stages to low-speed stages. During the switching process, the speed fluctuation is small, and it can also adapt to load changes, effectively coping with various complex working conditions.

[0116] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0117] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, electronic devices, or computer software program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0118] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, systems, electronic devices, or computer software program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A system that specifies functions in one or more boxes.

[0119] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including an instruction set implemented in a process. Figure 1 One or more processes and / or boxes Figure 1The function specified in one or more boxes.

[0120] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0121] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

Claims

1. A high-speed switching method in a sensorless control system for a permanent magnet synchronous motor, characterized in that the method... include: Set the switching frequency point between IF control and sliding control. and switching frequency bandwidth ; Based on the actual operating frequency of the motor With switching frequency points and switching frequency bandwidth The relationship between the two is used to calculate the smooth switching transition coefficient. ; The above is based on the actual operating frequency of the motor With switching frequency points and switching frequency bandwidth The relationship between the two is used to calculate the smooth switching transition coefficient. The methods include: Based on the smooth switching transition coefficient Determine the switching strategy and ensure a smooth, abrupt switching process; The switching process includes switching from IF control to sliding control, and switching from sliding control to IF control. The method for switching from synovial control to IF control includes: When the actual operating frequency of the motor Reduce to At that time, calculate the current difference between the speed loop output and the IF control in the sliding diaphragm control system. and angle difference ; Assign the angle controlled by the diaphragm to the angle estimated by the IF, and assign the speed loop output in the diaphragm control system to the current controlled by the IF. When the actual operating frequency of the motor Reduce to arrive During this period, the current and angle controlled by IF are compensated for during transition. The difference between the speed loop output and the current controlled by IF in the calculated sliding diaphragm control system and angle difference The methods specifically include: in, For the current controlled by IF; The method of assigning the angle controlled by the diaphragm to the angle estimated by the IF, and assigning the output of the speed loop in the diaphragm control system to the current controlled by the IF, specifically includes: in, The angle controlled by IF during switching. The angle estimated by the synovium during switching. This refers to the current controlled by IF during switching. The current output by the sliding diaphragm control speed ring; The method for compensating for the current and angle controlled by IF specifically includes: in, For the current controlled by IF, For IF to control the rotor position angle, This is the step angle corresponding to the IF control speed.

2. The high-speed switching method in the sensorless control system for permanent magnet synchronous motors according to claim 1, characterized in that, The method for switching from IF control to sliding control includes: When the actual operating frequency of the motor Increase to At that time, calculate the difference between the angle controlled by the IF at the switching point and the angle estimated by the sliding diaphragm. ; Assign the angle controlled by IF to the angle estimated by the diaphragm, and assign the current controlled by IF to the integral output of the speed loop in the diaphragm control system; When the actual operating frequency of the motor Increase to arrive During this period, the angle of the sliding diaphragm control is compensated, and the current is given by the speed loop output. In the process of compensating for the angle of the sliding diaphragm control, the torque current given by the speed loop is synchronously adjusted.

3. The high-speed switching method in the sensorless control system for permanent magnet synchronous motors according to claim 2, characterized in that, The difference between the angle controlled by IF at the calculation switching point and the angle estimated by the sliding film. The methods specifically include: in, The angle controlled by IF during switching. The angle estimated for the synovium.

4. The high-speed switching method in the sensorless control system for permanent magnet synchronous motors according to claim 3, characterized in that, The method of assigning the angle controlled by IF to the angle estimated by the diaphragm and assigning the current controlled by IF to the integral output of the speed loop in the diaphragm control system specifically includes: in, Angle estimated for the synovial membrane. This is the integral output of the sliding diaphragm control speed loop during switching. This is the current controlled by IF.

5. The high-speed switching method in the sensorless control system for permanent magnet synchronous motors according to claim 4, characterized in that, The method for compensating the angle of the sliding diaphragm control, with the current provided by the speed loop output, specifically includes: in, To control the rotor position angle using a sliding diaphragm, For the torque current of the sliding diaphragm control, The current output by the sliding diaphragm control speed ring.

Images