Phase voltage reconstruction method and device of permanent magnet synchronous motor, computer program product and rotor position observation method and device

Abstract

The invention discloses a phase voltage reconstruction method and device of a permanent magnet synchronous motor, a computer program product and a rotor position observation method and device.The phase voltage reconstruction method comprises the steps that three-phase PWM duty ratio signals and direct-current bus voltage of an inverter are collected, and ideal phase voltage is calculated through the duty ratio signals and the direct-current bus voltage; and dynamically correcting the error of the ideal phase voltage based on nonlinear characteristic compensation of IGBT / SiC. And on the basis of voltage reconstruction, a back electromotive force adaptive controller and a permanent magnet synchronous motor rotor position observer of an orthogonal phase-locked loop, full-speed-domain high-precision position estimation is realized by fusing a phase voltage reconstruction algorithm and expanding dynamic tracking capability of an EMF model and a QPLL, performance defects of a traditional method under low-speed and dynamic working conditions are overcome, and high-precision position estimation is realized. And the CPU resource consumption is high.

Description

Technical Field

[0001] The present invention relates to the technical field of sensorless control of permanent magnet synchronous motors, and in particular to a method and device for reconstructing the phase voltage of a permanent magnet synchronous motor, a computer program product, and a method and device for observing the rotor position. Background Art

[0002] Permanent magnet synchronous motors (PMSMs) are widely used in various high-performance drive systems, especially in the fields of industrial automation, new energy vehicles, and power tools. Their advantages lie in high efficiency, low loss, high power density, and excellent dynamic response characteristics, which make them play an important role in applications requiring high precision, high stability, and high reliability. In the control system of PMSMs, accurate estimation of the rotor position is crucial for achieving sensorless control efficiently and stably. Although the traditional position sensor-based control method can provide relatively accurate rotor position feedback, due to its disadvantages such as high cost, high assembly accuracy requirements, occupying space, easy signal interference, and high maintenance cost, many application scenarios choose to adopt sensorless control technology. Sensorless control technology replaces physical sensors by accurately estimating the rotor speed and position, thereby reducing the system cost and improving the system reliability to a certain extent, while avoiding performance degradation and maintenance costs caused by sensor failures.

[0003] In sensorless control technology, accurate estimation of the rotor position is the key to achieving high-performance control. As one of the important inputs of the rotor position observer in sensorless control, phase voltage reconstruction directly affects the accuracy of rotor position estimation. However, the noise, interference, and non-ideal factors during motor operation often make the phase voltage signal reconstruction process complex and difficult to achieve high-precision reconstruction. Some existing algorithms rely on fixed models and assumption conditions and are difficult to adapt to complex motor dynamic environments, so they cannot meet the requirements of high-precision control. Summary of the Invention

[0004] Aiming at the deficiencies of the above-mentioned existing technologies, the technical problem to be solved by the present invention is: how to provide a phase voltage reconstruction method for a permanent magnet synchronous motor that can provide a highly reliable reconstructed phase voltage input for sensorless control of a permanent magnet synchronous motor by dynamically compensating the nonlinear characteristics of IGBT / SiC and online parameter correction, and reducing the algorithm complexity.

[0005] To solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A phase voltage reconstruction method for a permanent magnet synchronous motor, which collects the three-phase PWM duty ratio signals and the DC bus voltage of an inverter, calculates the ideal phase voltage through the duty ratio signals and the DC bus voltage, and dynamically corrects the error of the ideal phase voltage based on the nonlinear characteristic compensation of IGBT / SiC.

[0007] As an optimization, the non-linear characteristic compensation of the IGBT / SiC includes:

[0008] Dead-time compensation: Inject a compensation time according to the switching current direction to correct the effective duty cycle;

[0009] Conduction voltage drop compensation: Calculate the voltage drop through the real-time current and the IGBT / SiC conduction characteristic curve:

[0010] ΔV x = sign(I x )·(V ce (|I x |)+V d ) (1)

[0011] where I x is the real-time current, V ce (|I x |) is the IGBT / SiC conduction characteristic curve, and V d is the freewheeling diode voltage drop;

[0012] Temperature compensation: Adjust the conduction voltage drop model parameters according to the IGBT / SiC junction temperature.

[0013] A computer program product includes a computer program, and when the computer program is executed by a computer, the method as described above is implemented.

[0014] A computer-readable storage medium stores a computer program, and when the computer program is executed by a computer, the method as described above is implemented.

[0015] A rotor position observation method based on an extended EMF and a QPLL. The reconstructed phase voltage obtained by the phase voltage reconstruction method as described above is subjected to a PARK coordinate transformation to obtain u α and u β , the measured phase current is subjected to a PARK coordinate transformation to obtain i α and i β , and u α and u β , i α and i β are input into an adaptive controller to obtain extended back electromotive force components and The extended back electromotive force components and are input into a quadrature phase-locked loop for quadrature signal demodulation, integration, and angle compensation to generate estimated values of the rotor position and speed.

[0016] As an optimization, the quadrature phase-locked loop dynamically adjusts its own bandwidth based on the motor speed error.

[0017] A rotor position observation device based on extended EMF and QPLL, comprising:

[0018] Phase voltage reconstruction module: used to execute the phase voltage reconstruction method as described above to generate the reconstructed phase voltage, and output u through PARK coordinate transformation α and u β ;

[0019] Adaptive controller: used to obtain i obtained by Clark coordinate based on the measured phase current α and i β , and synchronously input u α and u β to estimate and output the extended back electromotive force components and

[0020] Quadrature phase-locked loop: used to perform quadrature signal demodulation, integration and angle compensation on the extended back electromotive force components and and output the estimated values of the rotor angular velocity and position.

[0021] As an optimization, the quadrature phase-locked loop dynamically adjusts its own bandwidth based on the motor speed error.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) A phase voltage reconstruction method for dynamically compensating the non-linear characteristics of IGBT / SiC is proposed, which combines the SVPWM duty ratio, bus voltage and real-time IGBT / SiC parameters (dead time, conduction voltage drop, temperature characteristics) to achieve high-precision voltage estimation.

[0024] (2) Construct a voltage prediction model based on the switching state and duty ratio, and dynamically correct the compensation amount through online parameter identification.

[0025] (3) Hybrid observation architecture: The extended EMF model compensates for motor parameter changes, and the QPLL improves the dynamic performance through orthogonal phase discrimination and adaptive bandwidth adjustment.

[0026] (4) Parameter adaptive mechanism: The loop bandwidth of the QPLL is dynamically adjusted according to the speed error, reducing the bandwidth at low speed to suppress noise and increasing the bandwidth at high speed to speed up the response, ensuring high-speed dynamic tracking.

[0027] (5) Without complex filter algorithms and offline parameter identification, it is suitable for implementation in engineering embedded systems. Description of the Drawings

[0028] Figure 1 It is the structural block diagram of the phase voltage reconstruction module in the present invention;

[0029] Figure 2 This is the overall structural block diagram of the rotor position observation device in the present invention;

[0030] Figure 3 This is the structural block diagram of the EMF adaptive controller in the present invention;

[0031] Figure 4 This is the structural block diagram of the phase tracking loop of QPLL in the present invention. Detailed implementation manners

[0032] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. Components of the embodiments of the present invention generally described and illustrated in the figures herein can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the protection scope of the present invention.

[0033] As Figure 1 shown, the phase voltage reconstruction module adopts the phase voltage reconstruction method of a permanent magnet synchronous motor, and uses the Vce acquisition function of a general gate drive chip to collect the three-phase PWM duty ratio signals (D a 、D b 、D c ) of the inverter and the DC bus voltage (V dc ) in real time, and calculates the ideal phase voltages (V a0 、V b0 、V c0 ) through the duty ratio signals and the DC bus voltage:

[0034]

[0035] Based on the non-linear characteristic compensation of IGBT / SiC, dynamically correct the error of the ideal phase voltage.

[0036] The non-linear characteristic compensation of the IGBT / SiC includes:

[0037] Dead-time compensation: Inject compensation time according to the switching current direction to correct the effective duty ratio;

[0038] Conduction voltage drop compensation: Calculate the voltage drop through the real-time current and the IGBT / SiC conduction characteristic curve:

[0039] ΔV x = sign(I x )·(V ce (|I x |)+V d ) (1)

[0040] wherein, I x is the real-time current, V ce (|I x |) is the IGBT / SiC conduction characteristic curve, and V d is the freewheeling diode voltage drop;

[0041] Temperature compensation: Adjust the conduction voltage drop model parameters according to the IGBT / SiC junction temperature (Tj);

[0042] Finally, output the compensated phase voltage:

[0043] V x = V x0 -ΔV x (x = a, b, c) (3)

[0044] A computer program product includes a computer program which, when executed by a computer, implements the method as described above.

[0045] A computer-readable storage medium stores a computer program which, when executed by a computer, implements the method as described above.

[0046] A rotor position observation method based on extended EMF and QPLL, wherein the reconstructed phase voltage obtained by the phase voltage reconstruction method as described above is subjected to PARK coordinate transformation to obtain u α and u β , and the measured phase current is subjected to PARK coordinate transformation to obtain i α and i β , and u α and u β , i α and i β are input into an adaptive controller to obtain the extended back electromotive force components and The extended back electromotive force components and are input into a quadrature phase-locked loop for quadrature signal demodulation to generate an angular velocity signal, and after integration and angle compensation, a current operating condition angle signal is obtained:

[0047]

[0048] Generate the estimated values of the rotor position and the rotational speed .

[0049] Construct the back electromotive force model in the α-β coordinate system. R s and L s are the phase resistance and synchronous inductance of the motor, which can be measured in advance. and are the back electromotive forces in the α-β coordinate system and are also variables to be solved. Thus, the back electromotive forces and in the α-β coordinate system are u α and u β (terminal voltage in the α-β coordinate system), as well as the motor resistance R s and synchronous inductance L s , as well as i α and i β to form a system of binary linear equations:

[0050]

[0051] and are obtained through an adaptive regulator. The adaptive controller calculates the α and β axis voltages α and i β based on the measured phase currents of i and calculated inside the adaptive controller. and The difference between the reconstructed u α and u β of the phase voltage and the axis voltage and is applied to the resistive-inductive load (Rs and Ls), and the corresponding α and β axis currents (i.e., and ) will be generated. In practical applications, the differential terms of the above currents (i.e., and ) cannot be directly calculated because some sampling noises will inevitably be generated during the sampling process. Furthermore, directly differentiating the sampled current will amplify the sampling noise violently, and the error will increase further with the increase of the switching frequency. Therefore, an adaptive controller is adopted. To ensure the tracking performance of the observer in the low-speed and high-speed ranges, a sliding-mode control type back electromotive force observer is combined with a proportional control type back electromotive force observer. When the current error is small, proportional control is adopted, and when the error is large, sliding-mode control is adopted.

[0052] The orthogonal phase-locked loop dynamically adjusts its own bandwidth based on the motor speed error:

[0053]

[0054] Ensure noise suppression at low speeds and fast tracking at high speeds.

[0055] As Figure 2 and Figure 4 shown, a rotor position observation device based on extended EMF and QPLL includes:

[0056] Phase voltage reconstruction module: used to execute the phase voltage reconstruction method as described above to generate the reconstructed phase voltage, and output u α and u β through PARK coordinate transformation;

[0057] Adaptive controller: used to obtain i α and i β based on the measured phase current through PARK coordinates, and together with the synchronously input u α and u β to estimate and output the extended back electromotive force components and

[0058] Orthogonal phase-locked loop: used to demodulate the extended back electromotive force components and into orthogonal signals to generate an angular velocity signal, and after integration and angle compensation, output the estimated values of the rotor angular velocity and position.

[0059] The orthogonal phase-locked loop dynamically adjusts its own bandwidth based on the motor speed error:

[0060] K p = K p0 + k·|Δω| (6)

[0061] Ensure noise suppression at low speeds and fast tracking at high speeds.

[0062] Through simulation experiments, the present invention has a position error <1° at a low speed of 0.5 Hz, a tracking delay <2 ms when the rotational speed suddenly changes by 200% of the rated speed, and the accuracy is improved by more than 40% compared with the traditional PLL. Without increasing the hardware cost, the present invention proposes a rotor position observer based on extended back electromotive force (EMF) and orthogonal phase-locked loop (QPLL). By fusing the phase voltage reconstruction and the fast tracking ability of QPLL, high-precision position estimation in the low, medium, and high speed ranges is achieved, and the dynamic response and anti-interference ability are enhanced, solving the performance defects of traditional methods in low-speed and dynamic working conditions, as well as the problem of high CPU resource consumption.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the technical solutions. Those of ordinary skill in the art should understand that any modifications or equivalent replacements made to the technical solutions of the present invention without departing from the purpose and scope of the present technical solution shall be covered by the scope of the claims of the present invention.

Claims

1. A method for reconstructing the phase voltage of a permanent magnet synchronous motor, characterized in that: Collect the three-phase PWM duty ratio signals and the DC bus voltage of the inverter, calculate the ideal phase voltage through the duty ratio signals and the DC bus voltage, and dynamically correct the error of the ideal phase voltage based on the nonlinear characteristic compensation of IGBT / SiC.

2. The method for reconstructing the phase voltage of a permanent magnet synchronous motor according to claim 1, wherein: The nonlinear characteristic compensation of IGBT / SiC includes: Dead-time compensation: Inject compensation time according to the switching current direction to correct the effective duty ratio; Conduction voltage drop compensation: Calculate the voltage drop through the real-time current and the IGBT / SiC conduction characteristic curve; ΔV x = sign(I x )·(V ce (|I x |)+V d ) (1) Among them, I x is the real-time current, V ce (|I x |) is the IGBT / SiC conduction characteristic curve, V d is the freewheeling diode voltage drop; Temperature compensation: Adjust the parameters of the conduction voltage drop model according to the IGBT / SiC junction temperature.

3. A computer program product, characterized in that: It includes a computer program, and when the computer program is executed by a computer, it implements the method described in any one of claims 1 or 2.

4. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a computer, it implements the method described in any one of claims 1 or 2.

5. A rotor position observation method based on extended EMF and QPLL, characterized in that: The reconstructed phase voltage obtained by the method according to any one of claims 1 or 2 is transformed through PARK coordinates to obtain u α and u β The measured phase current is transformed through PARK coordinates to obtain i α and i β u α and u β i α and i β are input into an adaptive controller to obtain extended back electromotive force components and The extended back electromotive force components and are input into a quadrature phase-locked loop for quadrature signal demodulation, integration, and angle compensation to generate estimated values of the rotor angular velocity and position.

6. The rotor position observation method based on extended EMF and QPLL according to claim 5, characterized in that: The orthogonal phase-locked loop dynamically adjusts its own bandwidth based on the motor speed error.

7. A rotor position observation device based on extended EMF and QPLL, characterized in that: It includes: Phase voltage reconstruction module: used to execute the method described in any one of claims 1 or 2 to generate the reconstructed phase voltage, and output u through PARK coordinate transformation α and u β ; Adaptive controller: used to obtain \(i_{d}\) and \(i_{q}\) through PARK coordinate transformation based on the measured phase current, and estimate and output the extended back electromotive force components together with the synchronously input \(u_{d}\) and \(u_{q}\). α and \(i_{q}\) β , together with the synchronously input \(u_{d}\) α and \(u_{q}\) β to estimate and output the extended back electromotive force components and Orthogonal Phase-Locked Loop: used to perform orthogonal signal demodulation, integration, and angle compensation on the extended back electromotive force component and and output the estimated values of the rotor angular velocity and position.

8. The rotor position observation device based on extended EMF and QPLL according to claim 7, characterized in that: The orthogonal phase-locked loop dynamically adjusts its own bandwidth based on the motor speed error.

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