A vector control circuit and method for a permanent magnet synchronous shaft motor based on AC phase shift

Abstract

The application is a kind of vector control circuit and method of permanent magnet synchronous shaft motor based on AC phase shift. The application relates to the technical field of permanent magnet synchronous shaft motor vector control, and can perform vector control on the permanent magnet synchronous shaft motor. The three-phase AC power passes through the above controllable phase shifter, and through the conduction and shutdown of the corresponding thyristor switch, six different phase shifts can be generated. According to the average value equivalent principle, the appropriate phase shift is selected, the most ideal stator voltage synthesis vector is obtained, and the vector control of the permanent magnet synchronous shaft motor is completed. The application can make the shaft motor directly use three-phase AC power, without the need of AC-DC-AC power change, and simplify the ship power grid. At the same time, the application is the control of the stator voltage synthesis vector, can improve the dynamic response of the permanent magnet synchronous motor, and is more suitable for digital control system.

Description

Technical Field

[0001] This invention relates to the field of vector control technology for permanent magnet synchronous shaft motors, and is a vector control circuit and method for permanent magnet synchronous shaft motors based on AC phase shifting. Background Technology

[0002] As a new type of ship propulsion, hybrid power combines mechanical (propulsion main engine) propulsion with electric (generator set) propulsion. Depending on different operating conditions, it can switch between the propulsion main engine and shaft motor to drive the propeller, or both to drive the propeller. This can effectively solve the problems of ships operating under varying conditions in a short period of time and the requirement for large thrust output, reduce the ship's total fuel consumption and emissions, and improve the reliability of ship operation.

[0003] In this system, the shaft-driven motor serves as the link between mechanical and electrical energy, and it is also responsible for energy distribution throughout the hybrid power system. Therefore, the control system of the shaft-driven motor is particularly important. Currently, permanent magnet synchronous motors are generally used for shaft-driven motors, and their control systems typically employ SVPWM vector control technology. However, this control technology requires AC-DC-AC energy conversion or a DC bus, complicating the ship's electrical grid.

[0004] The purpose of this invention is to provide a vector control technology for permanent magnet synchronous shaft motors based on AC phase shifting. This technology allows the shaft motor to directly use three-phase AC power, eliminating the need for AC-DC-AC power conversion and simplifying the ship's electrical grid. Furthermore, this invention controls the stator voltage synthesis vector, improving the dynamic response of the permanent magnet synchronous motor and making it well-suited for digital control systems. Summary of the Invention

[0005] This invention provides a vector control scheme for a permanent magnet synchronous shaft motor that directly uses alternating current. Compared to the AC-DC-AC control method, this invention has better energy conversion efficiency. Therefore, this invention provides a vector control circuit and method for a permanent magnet synchronous shaft motor based on AC phase shifting.

[0006] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0007] This invention provides a vector control circuit and method for a permanent magnet synchronous shaft motor based on AC phase shifting. The invention provides the following technical solutions:

[0008] A vector control circuit for a permanent magnet synchronous shaft motor based on AC phase shifting, the circuit includes: three-phase AC power (A, B, C), and corresponding three-phase controllable resistor-capacitor-inductor phase shifting circuit bridge, variable phase sequence circuit, and PMSM;

[0009] The controllable RC inductor phase-shifting circuit bridge of phase A includes: thyristor switch S4, thyristor switch S5, thyristor switch S6, thyristor switch S7, thyristor switch S8, inductor L1, inductor L2, capacitor C1, capacitor C2 and load resistor R1; the variable phase sequence circuit of phase A includes: thyristor switch S1, thyristor switch S2 and thyristor switch S3;

[0010] The controllable RC inductor phase-shifting circuit bridge of phase B includes: thyristor switch S4', thyristor switch S5', thyristor switch S6', thyristor switch S7', thyristor switch S8', inductor L1', inductor L2', capacitor C1', capacitor C2', and load resistor R1'; the variable phase sequence circuit of phase B includes: thyristor switch S1', thyristor switch S2', and thyristor switch S3';

[0011] The controllable RC inductor phase-shifting circuit bridge of phase C includes: thyristor switch S4”, thyristor switch S5”, thyristor switch S6”, thyristor switch S7V’, thyristor switch S8”, inductor L1”, inductor L2”, capacitor C1”, capacitor C2”, and load resistor R1”; the variable phase sequence circuit of phase C includes: thyristor switch S1”, thyristor switch S2”, and thyristor switch S3”;

[0012] The A-phase AC voltage source is connected to thyristor switches S1, S2, and S3. Thyristor switch S1 is connected to inductor L1, and inductor L1 is connected to capacitor C2. Thyristor switches S4 and S5 are connected in parallel to inductor L1 and capacitor C2, respectively. Capacitor C2 is connected to PMSM and thyristor switch S8. Thyristor switch S8 is connected to inductor L2 and load resistor R1. Inductor L2 is connected to capacitor C1. Thyristor switches S6 and S7 are connected in parallel to capacitor C1 and inductor L2, respectively. Load resistor R1 and capacitor C1 are both grounded.

[0013] Preferably, the B-phase AC voltage source is connected to thyristor switches S3, S1', and S2'. Thyristor switch S1' is connected to thyristor switch S2, inductor L1', and S3'. Inductor L1' is connected to capacitor C2'. Thyristor switches S4' and S5' are connected in parallel with inductor L1' and capacitor C2', respectively. Capacitor C2' is connected to PMSM and thyristor switch S8'. Thyristor switch S8' is connected to inductor L2' and load resistor R1'. Inductor L2' is connected to capacitor C1'. Thyristor switches S6' and S7' are connected in parallel with capacitor C1' and inductor L2', respectively. Load resistor R1' and capacitor C1' are both grounded.

[0014] Preferably, the C-phase AC voltage source is connected to thyristor switch S1” and thyristor switch S2”, thyristor switch S2” is connected to inductor L1, thyristor switch S1” is connected to thyristor switch S3”, thyristor switch S2” and inductor L1”, inductor L1” is connected to capacitor C2, thyristor switches S4” and S5” are connected in parallel to inductor L1” and capacitor C2” respectively, capacitor C2” is connected to PMSM and thyristor switch S8, thyristor switch S8” is connected to inductor L2” and load resistor R1, inductor L2” is connected to capacitor C1, thyristor switches S6” and S7” are connected in parallel to capacitor C1” and inductor L2” respectively, and load resistor R1” and capacitor C1” are both grounded.

[0015] Preferably, by using thyristor switches to turn on and off on each phase of the three-phase AC power, the phase of the composite vector of the three-phase AC power can be changed selectively. The selectable phase changes are 60°, 0°, and -60°.

[0016] Preferably, an inductor is connected in parallel with the resistor in the controllable RC inductor phase-shifting circuit bridge. By adjusting appropriate parameters, U can be made... a Voltage phase ratio U A It lags by 60°, but the amplitude remains unchanged;

[0017] By connecting a capacitor in parallel with the resistor and adjusting the appropriate parameters, U can be made... a Voltage phase ratio U A It is 60° ahead, but the amplitude remains the same.

[0018] A method for synthesizing vector phase in three-phase alternating current, the method comprising:

[0019] When thyristor switch S1 is on and thyristor switches S2 and S3 are off, with the phase sequence Aa, Bb, Cc, the output three-phase AC composite vector is in phase with the three-phase AC power composite vector. When thyristor switch S2 is on and thyristor switches S1 and S3 are off, with the phase sequence Ab, Bc, Ca, the output three-phase AC composite vector is 120° ahead of the three-phase AC power composite vector. When thyristor switch S3 is on and thyristor switches S1 and S2 are off, with the phase sequence Ac, Ba, Cb, the output three-phase AC composite vector is 120° behind the three-phase AC power composite vector.

[0020] Preferably, the controllable phase shifter can perform six changes to the phase of the three-phase AC composite vector. The selectable phase changes are ±180°, ±120°, ±60°, and 0°, dividing the complex plane containing the voltage space vector into six regions.

[0021] Preferably, based on the stator position, the ideal stator voltage composite vector is calculated, and then the phase difference between the ideal stator voltage composite vector and the current three-phase AC power supply composite vector is calculated. Based on this phase difference, the region where the ideal stator voltage composite vector is located is determined. Two adjacent voltage composite vectors in this region are combined so that their average value over time is equal to the ideal stator voltage composite vector, thus completing the vector control of the permanent magnet synchronous shaft motor based on AC phase shift.

[0022] A computer-readable storage medium having a computer program stored thereon, which is executed by a processor to implement a method for synthesizing vector phases of three-phase alternating current.

[0023] A computer device includes a memory and a processor, the memory storing a computer program, the processor executing the computer program to implement a method for synthesizing vector phases of three-phase alternating current.

[0024] The present invention has the following beneficial effects:

[0025] This invention enables vector control of a permanent magnet synchronous shaft motor. Three-phase AC power, passing through the aforementioned controllable phase shifter, generates six different phase shifts through the switching on and off of corresponding thyristor switches. Based on the principle of average value equivalence, a suitable phase shift is selected to obtain the ideal stator voltage composite vector, thus completing the vector control of the permanent magnet synchronous shaft motor.

[0026] This invention allows shaft-driven motors to directly use three-phase AC power, eliminating the need for AC-DC-AC power conversion and simplifying the ship's electrical grid. Furthermore, this invention controls the stator voltage synthesis vector, improving the dynamic response of permanent magnet synchronous motors and making it well-suited for digital control systems. Attached Figure Description

[0027] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0028] Figure 1 This is a circuit diagram of a resistor-capacitor phase-shifting bridge, characterized by an inductor connected in parallel with the resistor.

[0029] Figure 2 This is a circuit diagram of a resistive-inductive phase-shifting bridge, characterized by a capacitor connected in parallel with the resistor.

[0030] Figure 3 It is a three-phase controllable RC (inductive) phase-shifting bridge circuit diagram that integrates phase lead and lag functions;

[0031] Figure 4 This is a three-phase alternating current variable phase sequence circuit diagram;

[0032] Figure 5 This is the circuit diagram of a controllable phase shifter;

[0033] Figure 6 It is a voltage space vector diagram;

[0034] Figure 7 This is a control flowchart for vector control of a permanent magnet synchronous shaft motor based on AC phase shifting. Detailed Implementation

[0035] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.

[0036] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0037] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0038] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0039] The present invention will be described in detail below with reference to specific embodiments. Specific Implementation Example 1:

[0041] according to Figures 1 to 7 As shown, the specific optimized technical solution adopted by the present invention to solve the above-mentioned technical problems is: The present invention relates to a vector control circuit and method for a permanent magnet synchronous shaft motor based on AC phase shifting.

[0042] A vector control circuit for a permanent magnet synchronous shaft motor based on AC phase shifting, the circuit includes: three-phase AC power (A, B, C), and corresponding three-phase controllable resistor-capacitor-inductor phase shifting circuit bridge, variable phase sequence circuit, and PMSM;

[0043] The controllable RC inductor phase-shifting circuit bridge of phase A includes: thyristor switch S4, thyristor switch S5, thyristor switch S6, thyristor switch S7, thyristor switch S8, inductor L1, inductor L2, capacitor C1, capacitor C2 and load resistor R1; the variable phase sequence circuit of phase A includes: thyristor switch S1, thyristor switch S2 and thyristor switch S3;

[0044] The controllable RC inductor phase-shifting circuit bridge of phase B includes: thyristor switch S4', thyristor switch S5', thyristor switch S6', thyristor switch S7', thyristor switch S8', inductor L1', inductor L2', capacitor C1', capacitor C2', and load resistor R1'; the variable phase sequence circuit of phase B includes: thyristor switch S1', thyristor switch S2', and thyristor switch S3';

[0045] The controllable RC inductor phase-shifting circuit bridge of phase C includes: thyristor switch S4”, thyristor switch S5”, thyristor switch S6”, thyristor switch S7V’, thyristor switch S8”, inductor L1”, inductor L2”, capacitor C1”, capacitor C2”, and load resistor R1”; the variable phase sequence circuit of phase C includes: thyristor switch S1”, thyristor switch S2”, and thyristor switch S3”;

[0046] The A-phase AC voltage source is connected to thyristor switches S1, S2, and S3. Thyristor switch S1 is connected to inductor L1, and inductor L1 is connected to capacitor C2. Thyristor switches S4 and S5 are connected in parallel to inductor L1 and capacitor C2, respectively. Capacitor C2 is connected to PMSM and thyristor switch S8. Thyristor switch S8 is connected to inductor L2 and load resistor R1. Inductor L2 is connected to capacitor C1. Thyristor switches S6 and S7 are connected in parallel to capacitor C1 and inductor L2, respectively. Load resistor R1 and capacitor C1 are both grounded.

[0047] Phase B AC voltage source is connected to thyristor switches S3, S1', and S2'. Thyristor switch S1' is connected to thyristor switch S2, inductor L1', and S3'. Inductor L1' is connected to capacitor C2'. Thyristor switches S4' and S5' are connected in parallel to inductor L1' and capacitor C2', respectively. Capacitor C2' is connected to PMSM and thyristor switch S8'. Thyristor switch S8' is connected to inductor L2' and load resistor R1'. Inductor L2' is connected to capacitor C1'. Thyristor switches S6' and S7' are connected in parallel to capacitor C1' and inductor L2', respectively. Load resistor R1' and capacitor C1' are both grounded.

[0048] The C-phase AC voltage source is connected to thyristor switch S1” and thyristor switch S2”. Thyristor switch S2” is connected to inductor L1. Thyristor switch S1” is connected to thyristor switch S3”, thyristor switch S2” and inductor L1”. Inductor L1” is connected to capacitor C2. Thyristor switches S4” and S5” are connected in parallel to inductor L1” and capacitor C2” respectively. Capacitor C2” is connected to PMSM and thyristor switch S8. Thyristor switch S8” is connected to inductor L2” and load resistor R1. Inductor L2” is connected to capacitor C1. Thyristor switches S6” and S7” are connected in parallel to capacitor C1” and inductor L2” respectively. Load resistor R1” and capacitor C1” are both grounded.

[0049] By using thyristor switches to turn on and off on each phase of the three-phase alternating current, the phase of the composite vector of the three-phase alternating current can be selectively changed. The selectable phase changes are 60°, 0°, and -60°.

[0050] By connecting an inductor in parallel with the resistor in a controllable RC inductor phase-shifting bridge circuit and adjusting appropriate parameters, U can be made... a Voltage phase ratio U A It lags by 60°, but the amplitude remains unchanged;

[0051] By connecting a capacitor in parallel with the resistor and adjusting the appropriate parameters, U can be made... a Voltage phase ratio U A It is 60° ahead, but the amplitude remains the same. Specific Implementation Example 2:

[0053] The only difference between Embodiment 2 and Embodiment 1 of this application is that:

[0054] The controllable phase shifter in this invention can be connected between a three-phase AC power supply and a permanent magnet synchronous shaft motor. Terminals ABC are connected to the three-phase AC power supply, and terminals abc are connected to the stator windings of the permanent magnet synchronous shaft motor. The thyristor switches of the controllable phase shifter are controlled by a pre-compiled digital circuit (1 indicates conduction, 0 indicates deactivation). The corresponding thyristor switches for each phase are simultaneously turned on or off. Specific phase shifting methods are shown in Table 1.

[0055] Table 1 Relationship between thyristor switching combinations and phase shift

[0056] 1 1 0 0 1 1 0 0° 2 1 0 0 1 0 1 -60° 3 1 0 0 0 1 1 60° 4 0 1 0 1 1 0 120° 5 0 1 0 1 0 1 60° 6 0 1 0 0 1 1 180° 7 0 0 1 1 1 0 -120° 8 0 0 1 1 0 1 -180° 9 0 0 1 0 1 1 -60°

[0057] Table 1 shows six possible phases that can alter the three-phase AC voltage composite vector. These six basic voltage composite vectors are mapped as shown in the attached table. Figure 6 In the complex plane shown, the voltage space vector diagram can be obtained, which divides the complex plane into 6 regions. When the ideal stator voltage composite vector is in a certain region, based on the principle of average value equivalence, it can be obtained by different combinations of two adjacent basic voltage vectors that make up that region in time.

[0058] like Figure 7 The diagram shows the control flowchart for vector control of a permanent magnet synchronous shaft motor based on AC phase shifting. First, the rotor position needs to be acquired to obtain the rotor voltage vector. Then, the phase difference between the calculated vector and the synthesized vector of the power supply voltage is calculated. If the phase difference is between -60° and 60°, thyristor switch S1 is turned on, and thyristor switches S2 and S3 are turned off; if the phase difference is between 60° and 180°, thyristor switch S2 is turned on, and thyristor switches S1 and S3 are turned off; if the phase difference is between -60° and -180°, thyristor switch S3 is turned on, and thyristor switches S1 and S2 are turned off. Next, the phase difference between the rotor voltage vector and the newly adjusted power supply voltage composite vector is calculated. If the phase difference is between 0 and 60°, the combination of thyristor switches S4, S5, S6, and S7 being on and thyristor switch S8 being off, and the combination of thyristor switches S5, S7, and S8 being on and thyristor switches S4 and S6 being off, will cause the average value of the stator voltage composite vector over time to coincide with the rotor voltage composite vector. If the phase difference is between 0 and -60°, the combination of thyristor switches S4, S5, S6, and S7 being on and thyristor switch S8 being off, and the combination of thyristor switches S4, S6, and S8 being on and thyristor switches S5 and S7 being off, will cause the average value of the stator voltage composite vector over time to coincide with the rotor voltage composite vector.

[0059] In summary, this invention discloses a vector control circuit and method for a permanent magnet synchronous shaft motor based on AC phase shifting. This circuit, called a controllable phase shifter, specifically includes a controllable RC (inductive) phase shifting circuit bridge and a variable phase sequence circuit. Using the controllable phase shifter of this invention, three-phase AC power can be directly used to perform voltage vector control on the permanent magnet synchronous shaft motor, resulting in higher energy utilization compared to AC-DC-AC control systems. Specific Implementation Example 3:

[0061] The only difference between Embodiment 3 and Embodiment 2 of this application is that:

[0062] As attached Figure 1 The diagram shows a circuit bridge that can change the phase of an alternating current (AC) circuit. In a resistor-capacitor (RC) phase-shifting bridge, an inductor is connected in parallel with a resistor. By adjusting appropriate parameters, U can be changed. a Voltage phase ratio U A It lags by 60°, but the amplitude remains unchanged. When the thyristor switch is turned off, U a with U A In phase, when the thyristor switch is turned on, U a Voltage phase ratio U A Lag by 60°.

[0063] As attached Figure 2 The diagram shows a circuit bridge that can change the phase of an alternating current (AC) circuit. In a resistive-inductive phase-shifting bridge, a capacitor is connected in parallel with the resistor. By adjusting appropriate parameters, U can be changed. a Voltage phase ratio U A Leads by 60°, but the amplitude remains unchanged. When the thyristor switch is turned off, U a with U A In phase, when the thyristor switch is turned on, U a Voltage phase ratio U A 60° ahead.

[0064] A vector control circuit for a permanent magnet synchronous shaft motor based on AC phase shifting, the circuit includes: three-phase AC power (A, B, C), and corresponding three-phase controllable resistor-capacitor-inductor phase shifting circuit bridge, variable phase sequence circuit, and PMSM;

[0065] The controllable RC inductor phase-shifting circuit bridge of phase A includes: thyristor switch S4, thyristor switch S5, thyristor switch S6, thyristor switch S7, thyristor switch S8, inductor L1, inductor L2, capacitor C1, capacitor C2 and load resistor R1; the variable phase sequence circuit of phase A includes: thyristor switch S1, thyristor switch S2 and thyristor switch S3;

[0066] The controllable RC inductor phase-shifting circuit bridge of phase B includes: thyristor switch S4', thyristor switch S5', thyristor switch S6', thyristor switch S7', thyristor switch S8', inductor L1', inductor L2', capacitor C1', capacitor C2', and load resistor R1'; the variable phase sequence circuit of phase B includes: thyristor switch S1', thyristor switch S2', and thyristor switch S3';

[0067] The controllable RC inductor phase-shifting circuit bridge of phase C includes: thyristor switch S4”, thyristor switch S5”, thyristor switch S6”, thyristor switch S7V’, thyristor switch S8”, inductor L1”, inductor L2”, capacitor C1”, capacitor C2”, and load resistor R1”; the variable phase sequence circuit of phase C includes: thyristor switch S1”, thyristor switch S2”, and thyristor switch S3”;

[0068] The A-phase AC voltage source is connected to thyristor switches S1, S2, and S3. Thyristor switch S1 is connected to inductor L1, and inductor L1 is connected to capacitor C2. Thyristor switches S4 and S5 are connected in parallel to inductor L1 and capacitor C2, respectively. Capacitor C2 is connected to PMSM and thyristor switch S8. Thyristor switch S8 is connected to inductor L2 and load resistor R1. Inductor L2 is connected to capacitor C1. Thyristor switches S6 and S7 are connected in parallel to capacitor C1 and inductor L2, respectively. Load resistor R1 and capacitor C1 are both grounded.

[0069] The B-phase AC voltage source is connected to thyristor switches S3, S1', and S2'.

[0070] Thyristor switch S1' is connected to thyristor switch S2, inductor L1' and thyristor switch S3'. Inductor L1' is connected to capacitor C2'. Thyristor switches S4' and S5' are connected in parallel to inductor L1' and capacitor C2' respectively. Capacitor C2' is connected to PMSM and thyristor switch S8'. Thyristor switch S8' is connected to inductor L2' and load resistor R1'. Inductor L2' is connected to capacitor C1'. Thyristor switches S6' and S7' are connected in parallel to capacitor C1' and inductor L2' respectively. Load resistor R1' and capacitor C1' are both grounded.

[0071] The C-phase AC voltage source is connected to thyristor switch S1” and thyristor switch S2”. Thyristor switch S2” is connected to inductor L1. Thyristor switch S1” is connected to thyristor switch S3”, thyristor switch S2” and inductor L1”. Inductor L1” is connected to capacitor C2. Thyristor switches S4” and S5” are connected in parallel to inductor L1” and capacitor C2” respectively. Capacitor C2” is connected to PMSM and thyristor switch S8. Thyristor switch S8” is connected to inductor L2” and load resistor R1. Inductor L2” is connected to capacitor C1. Thyristor switches S6” and S7” are connected in parallel to capacitor C1” and inductor L2” respectively. Load resistor R1” and capacitor C1” are both grounded.

[0072] As attached Figure 3 The diagram shows the integration of the above circuit diagram onto each phase of a three-phase AC power supply, where the parameters of the components in each phase should be identical. By controlling the on and off states of the thyristor switches (the thyristor switches of the same name in each phase are simultaneously turned on or off), U can be controlled. abc Phase ratio U of the voltage composite vector ABC It is either 60° ahead, 60° behind, or in phase.

[0073] As attached Figure 4 The diagram illustrates a method for changing the phase of a three-phase AC power composite vector by switching the phase sequence of the three-phase AC power supply. The corresponding thyristor switches for each phase are simultaneously turned on or off. When thyristor switch S1 is on and thyristor switches S2 and S3 are off, with a phase sequence of Aa, Bb, Cc, the output three-phase AC power composite vector is in phase with the three-phase AC power supply composite vector. When thyristor switch S2 is on and thyristor switches S1 and S3 are off, with a phase sequence of Ab, Bc, Ca, the output three-phase AC power composite vector leads the three-phase AC power supply composite vector by 120°. When thyristor switch S3 is on and thyristor switches S1 and S2 are off, with a phase sequence of Ac, Ba, Cb, the output three-phase AC power composite vector lags the three-phase AC power supply composite vector by 120°.

[0074] As attached Figure 5 The diagram shows a combination of the two control circuits mentioned above for changing the composite vector phase of a three-phase AC voltage, called a controllable phase shifter. By controlling the on and off states of the corresponding thyristor switches, the phase of U can be changed. abc The phase of the voltage composite vector (selectable phase changes are ±180°, ±120°, ±60°, and 0°).

[0075] Using the aforementioned controllable phase shifter, vector control of a permanent magnet synchronous shaft motor can be achieved. Three-phase AC power, passing through the controllable phase shifter, can generate six different phase shifts by controlling the on and off states of the corresponding thyristor switches. Based on the principle of average value equivalence, a suitable phase shift is selected to obtain the ideal stator voltage composite vector, thus completing the vector control of the permanent magnet synchronous shaft motor. Specific Implementation Example 4:

[0077] The only difference between Embodiment 4 and Embodiment 3 of this application is that:

[0078] This invention provides a method for synthesizing vector phase in three-phase alternating current, the method comprising:

[0079] When thyristor switch S1 is turned on, thyristor switches S2 and S3 are turned off, and the phase sequence is connected as Aa, Bb, ...

[0080] Cc, the output three-phase AC power vector is in phase with the output three-phase AC power vector; when thyristor switch S2 is on and thyristor switches S1 and S3 are off, and the phase sequence is Ab, Bc, Ca, the output three-phase AC power vector is 120° ahead of the output three-phase AC power vector; when thyristor switch S3 is on and thyristor switches S1 and S2 are off, and the phase sequence is Ac, Ba, Cb, the output three-phase AC power vector is 120° behind the output three-phase AC power vector.

[0081] Preferably, the controllable phase shifter can perform six changes to the phase of the three-phase AC composite vector. The selectable phase changes are ±180°, ±120°, ±60°, and 0°, dividing the complex plane containing the voltage space vector into six regions.

[0082] Based on the stator position, the ideal stator voltage composite vector is calculated, and then the phase difference between the ideal stator voltage composite vector and the current three-phase AC power composite vector is calculated. Based on this phase difference, the region where the ideal stator voltage composite vector is located is determined. Two adjacent voltage composite vectors in this region are combined so that their average value over time is equal to the ideal stator voltage composite vector, thus completing the vector control of the permanent magnet synchronous shaft motor based on AC phase shift. Specific Implementation Example 5:

[0084] The only difference between Embodiment 5 and Embodiment 4 of this application is that:

[0085] The present invention provides a computer-readable storage medium having a computer program stored thereon, which is executed by a processor to implement a method for synthesizing vector phases of three-phase alternating current. Specific Implementation Example Six:

[0087] The only difference between Embodiment Six and Embodiment Five of this application is that:

[0088] The present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement a method for synthesizing vector phase of three-phase alternating current.

[0089] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or N embodiments or examples. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of the present invention, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified. Any process or method described in the flowcharts or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more N executable instructions for implementing custom logical functions or processes, and the scope of preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order according to the functions involved, as will be understood by those skilled in the art to which embodiments of the invention pertain. The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection having one or N wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic device, and portable optical disc read-only memory (CDROM).Furthermore, the computer-readable medium can even be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory. It should be understood that various parts of the invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0090] The above description is merely a preferred embodiment of a vector control circuit and method for a permanent magnet synchronous shaft motor based on AC phase shifting. The scope of protection for such a circuit and method is not limited to the above embodiments; all technical solutions falling within this conceptual framework are within the protection scope of this invention. It should be noted that for those skilled in the art, any improvements and variations made without departing from the principles of this invention should also be considered within the protection scope of this invention.

Claims

1. A vector control circuit for a permanent magnet synchronous shaft motor based on AC phase shifting, characterized in that: The circuit includes: three-phase AC power supply (A, B, C), and corresponding three-phase controllable resistor-capacitor-inductor phase-shifting circuit bridge, variable phase sequence circuit, and PMSM; Phase A AC voltage source is connected to thyristor switches S1, S2, and S3. ，， Thyristor switch S1 is connected to inductor L1, inductor L1 is connected to capacitor C2, thyristor switches S4 and S5 are connected in parallel to inductor L1 and capacitor C2 respectively, capacitor C2 is connected to PMSM and thyristor switch S8, thyristor switch S8 is connected to inductor L2 and load resistor R1, inductor L2 is connected to capacitor C1, thyristor switches S6 and S7 are connected in parallel to capacitor C1 and inductor L2 respectively, and load resistor R1 and capacitor C1 are both grounded; Phase B AC voltage source connected to thyristor switch S3 and thyristor switch S1 ， and thyristor switch S2 ， thyristor switch S1 ， Connect thyristor switch S2 and inductor L1 ， and thyristor switch S3 ， Inductor L1 ， Connect capacitor C2 ， thyristor switch S4 ， thyristor switch S5 ， They are connected in parallel to inductor L1 ， and capacitor C2 ， Above, capacitor C2 ， Connect PMSM and thyristor switch S8 ， thyristor switch S8 ， Connecting inductor L2 ， and load resistor R1 ， Inductor L2 ， Connecting capacitor C1 ， thyristor switch S6 ， thyristor switch S7 ， Connected in parallel to capacitor C1 ， and inductor L2 ， Above, load resistor R1 ， and capacitor C1 ， All grounded; C-phase AC voltage source connected to thyristor switch S1 ，， and thyristor switch S2 ，， thyristor switch S2 ，， Connect inductor L1 and thyristor switch S1 ，， Connect thyristor switch S3 ，， thyristor switch S2 ， and inductor L1 ，， Inductor L1 ，， Connect capacitor C2 ，， thyristor switch S4 ，， thyristor switch S5 ，， They are connected in parallel to inductor L1 ，， and capacitor C2 ，， Above, capacitor C2 ，， Connect PMSM and thyristor switch S8 ，， thyristor switch S8 ，， Connecting inductor L2 ，， and load resistor R1 ，， Inductor L2 ，， Connecting capacitor C1 ，， thyristor switch S6 ，， thyristor switch S7 ，， Connected in parallel to capacitor C1 ，， and inductor L2 ，， Above, load resistor R1 ，， and capacitor C1 ，， All grounded; When thyristor switch S1 is on and thyristor switches S2 and S3 are off, with the phase sequence Aa, Bb, Cc, the output three-phase AC composite vector is in phase with the three-phase AC power composite vector. When thyristor switch S2 is on and thyristor switches S1 and S3 are off, with the phase sequence Ab, Bc, Ca, the output three-phase AC composite vector is 120° ahead of the three-phase AC power composite vector. When thyristor switch S3 is on and thyristor switches S1 and S2 are off, with the phase sequence Ac, Ba, Cb, the output three-phase AC composite vector is 120° behind the three-phase AC power composite vector.

2. The circuit according to claim 1, characterized in that: By using thyristor switches to turn on and off on each phase of the three-phase alternating current, the phase of the composite vector of the three-phase alternating current can be selectively changed. The selectable phase changes are 60°, 0°, and -60°.

3. The circuit according to claim 2, characterized in that: By connecting an inductor in parallel with the resistor in a controllable RC inductor phase-shifting circuit bridge and adjusting appropriate parameters, it is possible to... Voltage phase ratio It lags by 60°, but the amplitude remains unchanged; By connecting a capacitor in parallel with the resistor and adjusting the appropriate parameters, it can be made... Voltage phase ratio It is 60° ahead, but the amplitude remains the same.

4. The circuit according to claim 3, characterized in that: The controllable phase shifter can perform six phase changes on the three-phase AC composite vector. The selectable phase changes are ±180°, ±120°, ±60°, and 0°, dividing the complex plane containing the voltage space vector into six regions.

5. The circuit according to claim 4, characterized in that: Based on the stator position, the ideal stator voltage composite vector is calculated, and then the phase difference between the ideal stator voltage composite vector and the current three-phase AC power composite vector is calculated. Based on this phase difference, the region where the ideal stator voltage composite vector is located is determined. Two adjacent voltage composite vectors in this region are combined so that their average value over time is equal to the ideal stator voltage composite vector, thus completing the vector control of the permanent magnet synchronous shaft motor based on AC phase shift.

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