CN203219239U - Position sensorless motor control device for SDFT rotor position identification - Google Patents

Abstract

The utility model relates to a position sensor-less motor control device employing SDFT rotor position identification and belongs to the field of sensorless permanent magnet synchronous motor control technology. The position sensor-less motor control device comprises a position sensor-less control unit, a PC, an isolating circuit, a busbar voltage sampling unit, a stator winding current sampling unit, a three-phase uncontrolled rectifier bridge, a busbar energy storage capacitor bank, an IPM three-phase voltage source inverter, and a permanent magnet synchronous motor. On the basis of saliency of motors, through injection of high-frequency voltage drive, a high-frequency current response signal containing rotor position information is sensed in a stator winding and a position signal is extracted for vector control through SDFT algorithm, so that the effect of motor control without mechanical position sensors is achieved. The position sensor-less motor control device is suitable for both built-in permanent magnet synchronous motors and inset permanent magnet synchronous motors.

Description

Position sensorless motor control device for SDFT rotor position identification

technical field

The utility model relates to a position sensorless permanent magnet synchronous motor control device, which belongs to the technical field of sensorless permanent magnet synchronous motor vector control. the

Background technique

Permanent magnet synchronous motors have the advantages of high power density, simple structure, high efficiency, and superior control performance, and are widely used in CNC machine tools, medical equipment, and aerospace fields. The AC speed control system of high-performance permanent magnet synchronous motor needs to obtain the instantaneous position information of the rotor to realize the field orientation. In actual systems, sensors are usually used to detect the rotor position in real time. Commonly used sensors include: photoelectric encoders, resolvers, Hall position sensors, etc. The use of these independent sensors not only increases the cost of the control system, but also brings corresponding signal detection processing complexity and reliability problems. The use of mechanical sensors has great limitations in practical applications, which are manifested in the following aspects:

(1) For some devices with small capacity and low cost, position sensors with high precision and fast response are expensive, which significantly increases system costs and reduces market competitiveness. the

(2) The accuracy of the sensor is easily disturbed by external environmental conditions such as temperature, humidity, and vibration, and cannot be used in some harsh environments and special occasions such as high temperature, sealing, and dust. the

(3) The mechanical sensor installed on the shaft not only increases the moment of inertia of the motor rotor shaft, but also increases the axial space size of the motor, and improper installation will cause concentricity problems and reduce accuracy. the

Since the rotor position information is an indispensable and important physical quantity in the high-performance motor drive system, and the installation and use of the mechanical position sensor have the above-mentioned various defects, it is important to study the control method and device of the position sensorless permanent magnet synchronous motor. practical meaning. the

Contents of the invention

The utility model aims to solve the problems of high cost, complicated installation and maintenance, and poor reliability of the existing mechanical position sensor detection signal, and provides a position sensorless motor control device for SDFT rotor position identification. the

The technical scheme adopted in the utility model is:

The utility model SDFT rotor position recognition non-position sensor permanent magnet synchronous motor control device, which includes a non-position sensor control unit, a PC, an isolation circuit, a bus voltage sampling unit, a stator winding current sampling unit, a three-phase uncontrolled rectifier bridge, Bus energy storage capacitor bank, IPM three-phase voltage source inverter, permanent magnet synchronous motor. The three-phase uncontrolled rectifier bridge rectifies the three-phase alternating current into direct current to charge the bus energy storage capacitor bank, and the output of the bus energy storage capacitor bank is converted by the IPM three-phase voltage source inverter to provide variable frequency power for the stator winding; The output signal of the winding current sampling unit provides sampling current for the position sensorless control unit, and the driving signal output by the isolation circuit is used as the driving input signal of the IPM three-phase voltage source inverter. The output end of the sensorless control unit is connected to the input end of the isolation circuit, the drive signal output by the isolation circuit is connected to the drive input end of the IPM three-phase voltage source inverter, and the communication end of the sensorless control unit is connected to the PC; It is characterized in that the output end of the position sensorless control unit is connected with the input end of the isolation circuit, the input end of the position sensorless control unit is respectively connected with the output end of the bus voltage sampling unit and the output end of the stator winding current sampling unit, and the communication of the position sensorless control unit The end is connected with the communication end of the PC. the

The position sensorless control unit includes a rotational speed PI regulator, a q-axis current PI regulator, a d-axis current PI regulator, a high-frequency voltage generator, an inverse Park transformation unit, an SVPWM pulse modulator, a decoupling controller, and a Clark A transform unit, a first Park transform unit, a low-pass filter 1LPF, a low-pass filter 2LPF, a second Park transform unit, an SDFT unit, a PI regulator, and an integrator. In the position sensorless control unit, the rotor position angle and speed are identified by the SDFT unit and the PI regulator instead of the sensor detection. The high-frequency current signal output by the second Park transformation unit is used as the input of the SDFT unit and extracted by the SDFT unit. The rotor position information is then modulated by the PI regulator to obtain the rotational speed, and the rotational speed is obtained by the integrator to obtain the rotor position angle. The bus voltage sampling unit uses a Hall-type voltage sensor, and the stator winding current sampling unit uses a Hall-type current sensor. The isolation circuit is optocoupler isolation. The core microprocessor model of the position sensorless control unit is 32-bit DSP-TMS320F28335 of TI Company. the

The utility model has the advantages that no mechanical position sensor is needed, the salient polarity of the motor is used to inject high-frequency voltage excitation, and the high-frequency current response signal containing rotor position information is induced in the stator winding, which is extracted by SDFT (Slide Discrete Fourier Transform) The rotor position angle can be obtained by obtaining the amplitude of the high-frequency current components of the d and q axes and performing simple algebraic operations. Compared with the existing heterodyne method, there is no need for synchronous axis coordinate transformation and the use of band-pass filters and high-pass filters. , the structure is simple, and it is not affected by the initial phase of the injection signal, the precision is high, the response is fast, the cost is low, the maintenance is convenient, and it has wide practicability. the

Description of drawings

Fig. 1 is a schematic block diagram of the structure principle of the utility model. the

Fig. 2 is a structural schematic diagram of the SDFT rotor position identification sensorless control unit in the present invention. the

Detailed ways

Specific embodiment one: the present embodiment is described below in conjunction with Fig. 1, the position sensorless motor control device of the SDFT rotor position identification described in the present embodiment, it comprises a position sensorless control unit 1, PC machine 2, isolation circuit 3, busbar Voltage sampling unit 4, stator winding current sampling unit 5, three-phase uncontrolled rectifier bridge 6, bus energy storage capacitor bank 7, IPM three-phase voltage source inverter 8, permanent magnet synchronous motor 9. This device disconnects the switch K1 in the pre-charging circuit of the bus energy storage capacitor group 7 before connecting the three-phase AC power supply, and the three-phase AC power supply charges the bus energy storage capacitor group 7 through the three-phase uncontrolled rectifier bridge 6 after power-on , close the switch K1 after pre-charging to provide DC power for the IPM three-phase voltage source inverter 8, the bus voltage sampling unit 4 uses the LV28-P Hall-type voltage sensor of LEM Company, and its input terminal is connected to the bus energy storage capacitor The group 7 is connected, the output terminal is sent to the sensorless control unit 1, the IPM three-phase voltage source inverter 8 is connected to the permanent magnet synchronous motor 9, and the stator winding current sampling unit 5 is connected in series on the connection line, and the stator winding current sampling Unit 5 uses the LA28-NP Hall-type current sensor, its output terminal is connected to the input terminal of the Clark transformation unit 108 in the sensorless control unit 1, and the output terminal of the sensorless control unit 1 passes through the isolation circuit 3 to modulate the pulse The signal is input to the drive input terminal of the IPM three-phase voltage source inverter 8 to provide switching signals for the power device, and the communication terminal of the sensorless control unit 1 is connected to the PC 2 . the

最后经SVPWM脉冲调制器106输出开关信号，从定子绕组电流采样单元得到的电流i_a、i_b，经Clark变换单元108、第二Park变换单元109得到包含位置信息的高频电流经SDFT单元113提取幅值后进行简单的代数运算得到包含位置信息的误差信号

最后经PI调节器114得到转子位置角

再经过积分器115输出转速信号ω。  Specific embodiment 2: The present embodiment is described below in conjunction with FIG. 2 . This embodiment is a position sensorless control unit of a permanent magnet synchronous motor position sensorless control device based on the SDFT rotor position identification described in Embodiment 1, which includes a rotational speed PI adjustment 101, q-axis current PI regulator 102, d-axis current PI regulator 103, high-frequency voltage generator 104, inverse Park transformation unit 105, SVPWM pulse modulator 106, decoupling controller 107, Clark transformation unit 108, the first A Park transformation unit 109 , a low-pass filter 1LPF110 , a low-pass filter 2LPF111 , a second Park transformation unit 112 , an SDFT unit 113 , a PI regulator 114 , and an integrator 115 . The set ω ^ref is compared with the ω obtained by SDFT identification, and the q-axis current value i _qref is output through the rotational speed PI regulator 101, _{where idref} is the set value of the d-axis current, and the permanent magnet detected by the stator winding current sampling unit 5 The current ia _and i _b in the stator winding of the synchronous motor 9 are obtained by the Clark transformation unit 108, the first Park transformation unit 109, the low-pass filter 1LPF110, and the low-pass filter 2LPF111 to obtain the current _id and _iq , respectively, which are compared with After i _qref and _idref are compared, the current PI regulators 101, 102 output u _d , u _q , and then combine with the output of the decoupling controller 107 and the output of the high-frequency voltage generator 104 to obtain a voltage command value, and then The voltage command value in the two-phase stationary coordinate system is obtained through the inverse Park transformation unit 105

Finally, the switching signal is output by the SVPWM pulse modulator 106, and the current _ia , _ib obtained from the stator winding current sampling unit is passed through the Clark transformation unit 108 and the second Park transformation unit 109 to obtain the high-frequency current containing position information After the amplitude is extracted by the SDFT unit 113, a simple algebraic operation is performed to obtain an error signal containing position information

Finally, the rotor position angle is obtained by the PI regulator 114

Then the speed signal ω is output through the integrator 115 .

The method for identifying the position of the SDFT rotor in Embodiment 2 is described in detail below. The high-frequency voltage excitation injected in FIG. 2 is shown in Formula 1:

$\left[\begin{array}{c}{u}_{i\hat{d}}\\ u_{i\hat{q}}\end{array}\right]=\left|u_i\right|\left[\begin{array}{c}\sin {\mathrm{\ω}}_{i}t\\ \cos {\mathrm{\ω}}_{i}t\end{array}\right]$ (Formula 1)

为注入的高频电压，u_i为注入信号的幅值，ω_i为注入信号的频率。  In the formula

is the injected high-frequency voltage, u _i is the amplitude of the injected signal, and ω _i is the frequency of the injected signal.

其按照

旋转，其中θ为转子实际位置角，

为辨识得到的转子位置角，则在该坐标系下感应产生的高频电流响应如公式2所示：  In order to illustrate the theoretical basis of this method, a new coordinate system is introduced on the basis of the dq coordinate system

its according to

Rotation, where θ is the actual position angle of the rotor,

In order to identify the obtained rotor position angle, the high-frequency current response induced in this coordinate system is shown in Equation 2:

$\left\{\begin{array}{c}{i}_{\hat{d}}=-(I_{i0}+I_{i1}\cos \left(2\mathrm{\Δ\θ}\right))\cos {\mathrm{\ω}}_{i}t+I_{i1}\sin \left(2\mathrm{\Δ\θ}\right)\sin {\mathrm{\ω}}_{i}t\\ i_{\hat{q}}=-I_{i1}\sin \left(2\mathrm{\Δ\θ}\right)\cos {\mathrm{\ω}}_{i}t+(I_{i0}-I_{i1}\cos \left(2\mathrm{\Δ\θ}\right))\sin {\mathrm{\ω}}_{i}t\end{array}\right.$ (Formula 2)

则经SDFT单元113提取出的d、q轴高频电流幅值可以表示成公式3形式：  In the formula, L _d and L _q represent the inductance of the orthogonal and direct axes respectively, L _Σ =(L _d +L _q )/2, L _△ =(L _q -L _d )/2,

Then the d and q axis high-frequency current amplitudes extracted by the SDFT unit 113 can be expressed in the form of formula 3:

$\left\{\begin{array}{c}<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; i</span>}}_{\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; d</span>}}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; =</span>\sqrt{{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}\\ <span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; i</span>}}_{\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; q</span>}}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; =</span>\sqrt{{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}\end{array}\right.$

...

$<span\; class="notranslate">\; \&DoubleRightArrow;</span><span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; i</span>}}_{\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; d</span>}}}{<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; i</span>}}_{\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; q</span>}}}{<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 4</span>}{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; 0</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}<span\; class="notranslate">\; )</span>$

转化成

坐标系，变换矩阵为公式4所示：  According to Equation 3, if the PI regulator 114 is used to adjust the closed-loop error signal to 0 for extracting the rotor position angle, the error term needs to be simplified into a sin(2θ) form. Therefore, the

Converted to

coordinate system, the transformation matrix is shown in Formula 4:

$T_{{\hat{d}}^{\&prime;}{\hat{q}}^{\&prime;}\&Right\; Arrow;\hat{d}\hat{q}}=\left[\begin{array}{cc}\cos (\mathrm{\&Delta;\&theta;}-\frac{\mathrm{\&pi;}}{4})& \sin (\mathrm{\&Delta;\&theta;}-\frac{\mathrm{\&pi;}}{4})\\ -\sin (\mathrm{\&Delta;\&theta;}-\frac{\mathrm{\&pi;}}{4})& \cos (\mathrm{\&Delta;\&theta;}-\frac{\mathrm{\&pi;}}{4})\end{array}\right]$ (Formula 4)

The transformation of the above-mentioned coordinate system can be realized only by subtracting π/4 from the input angle of the second Park transformation unit 112, then in coordinate system

${\left|i_{\hat{d}}\right|}^2-{\left|i_{\hat{q}}\right|}^2=4I_{i1}\cos \left(2\mathrm{\&Delta;}{\mathrm{\&theta;}}^{\&prime;}\right)=4I_{i1}\cos \left(2(\mathrm{\&Delta;\&theta;}-\frac{\mathrm{\&pi;}}{4})\right)=4I_{i1}\sin \left(2\mathrm{\&Delta;\&theta;}\right)$ (Formula 5)

再经过积分器115得到转速 信号ω。  After being regulated by PI regulator 114 The output is the rotor position angle

Then the speed signal ω is obtained through the integrator 115.

Note: the angles mentioned in this utility model are all electrical angles. the

Claims (7)

1. A position sensorless motor control device for SDFT rotor position identification, characterized in that it includes a position sensorless control unit (1), a PC (2), an isolation circuit (3), a bus voltage sampling unit (4), a stator Winding current sampling unit (5), three-phase uncontrolled rectifier bridge (6), bus energy storage capacitor bank (7), IPM three-phase voltage source inverter (8), permanent magnet synchronous motor (9), three-phase The uncontrolled rectifier bridge (6) rectifies the three-phase alternating current to direct current to charge the bus energy storage capacitor bank (7), and the output of the bus energy storage capacitor bank (7) is frequency-converted by the IPM three-phase voltage source inverter (8) Finally, the variable frequency power supply is provided for the stator winding; the output signal of the stator winding current sampling unit (5) provides sampling current for the position sensorless control unit (1), and the driving signal output by the isolation circuit (3) is used as an IPM three-phase voltage source type Drive input signal for inverter (8). the 2. The position sensorless control unit (1) of the position sensorless motor control device for SDFT rotor position identification according to claim 1, characterized in that: the input terminals of the position sensorless control unit (1) are respectively sampled with the bus voltage The output terminal of the unit (4) is connected with the output terminal of the stator winding current sampling unit (5), the output signal of the sensorless control unit (1) is connected with the input signal terminal of the isolation circuit (3), and the sensorless control unit (1) The communication end is connected with the communication end of the PC (2). the 3. The position sensorless motor control device for SDFT rotor position identification according to claim 1, characterized in that: the position sensorless control unit (1) includes a rotational speed PI regulator (101), a q-axis current PI regulator device (102), d-axis current PI regulator (103), high-frequency voltage generator (104), inverse Park transformation unit (105), SVPWM pulse modulator (106), decoupling controller (107), Clark transformation Unit (108), first Park transform unit (109), low-pass filter 1LPF (110), low-pass filter 2LPF (111), second Park transform unit (112), SDFT unit (113), PI regulator (114), integrator (115). the 4. The position sensorless motor control device for SDFT rotor position identification according to claim 1, characterized in that: the rotor position angle and rotational speed in the position sensorless control unit (1) are passed through the SDFT unit (113) and The PI regulator (114) is identified rather than detected by the sensor. The high-frequency current signal output by the second Park transformation unit (112) is used as the input of the SDFT unit (113), and the rotor position information is extracted through the SDFT unit, and then passed through the PI The regulator (114) performs modulation to obtain the rotational speed, and the rotational speed obtains the rotor position angle through the integrator (115). the 5. The position sensorless motor control device for SDFT rotor position identification according to claim 1, characterized in that: the bus voltage sampling unit (4) uses a Hall-type voltage sensor, a stator winding current sampling unit ( 5) The Hall-type current sensor is used. the 6. The sensorless motor control device for SDFT rotor position identification according to claim 1, characterized in that: the isolation circuit (3) is optocoupler isolation. the 7. The position sensorless motor control device for SDFT rotor position identification according to claim 1 and claim 2, characterized in that: the core microprocessor model of the position sensorless control unit (1) is TI company 32-bit DSP-TMS320F28335. the

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