CN104320036A - Low-speed sensorless vector control system and method based on PMSM - Google Patents

Abstract

The invention discloses a low-speed sensorless vector control system and method based on a PMSM. A phase delay angle caused in the process of injecting high-frequency voltage sinusoidal signals to stator end current is detected in real time, real-time compensation is conducted on a conditioning signal phase angle, and therefore the steady-state error and the system stability of an existing PMSM sensorless vector control system realized through the high frequency injection method can be improved.

Description

Based on PMSM low speed vector control without position sensor system and method

Technical field

The present invention relates to a kind of controller based on improving high frequency pulsating voltage injection method, for the vector control of permagnetic synchronous motor position-sensor-free, more traditional high frequency pulsating voltage injection method permagnetic synchronous motor vector control without position sensor control system is compared, and substantially increases the precision of system, reliability.

Background technology

The vector control system of conventional highfrequency pulsating injection method permagnetic synchronous motor position-sensor-free mostly adopts and carries out demodulation by current detecting conditioned signal in the ideal case, the compensation of delay angle real-time tracking maybe can not be carried out in the time delay angle not having test system to cause, by compensating the delay angle real-time tracking that system causes the improvement of high frequency pulsating voltage injection method, improve steady-state error and the stability of New method for sensorless control technique of PMSM.

Summary of the invention

Goal of the invention

The present invention relates to a kind of based on PMSM low speed vector control without position sensor system and method, its object is exactly that steady-state error in conventional highfrequency pulsating voltage injection method control system is low, the problem of poor stability in order to solve.

Technical scheme

The present invention is achieved through the following technical solutions:

Based on PMSM low speed vector control without position sensor system, it is characterized in that: this system includes speed preset through vector control module and high frequency signal injection model calling to permagnetic synchronous motor, by being connected to vector control module to the current detecting filtering processing modules implement electric current loop closed loop of permanent-magnetic synchronous motor stator electric current, and then be connected to delay angle tracing compensation control module and speed by current detecting filtering processing module, corner estimation module, the compensation of delay angle tracing compensation control module is connected to speed, corner estimation module, Negotiation speed, corner estimation module realizes speed closed loop.

A kind of as mentioned above based on the control method of PMSM low speed vector control without position sensor system, it is characterized in that: the delay angle of the high-frequency voltage signal injected to the high-frequency current signal detected is carried out to real-time tracking and then realize real-Time Compensation, reach the operation of the minimum steady-state error of whole system, step is as follows:

(1) system is by the injection of high frequency pulsating voltage signal, by the i detecting permanent-magnetic synchronous motor stator side electric current _q1transform component, obtains motor speed, position by filter, phase-locked loop process; In signal condition process, need to detect the delay angle produced by system device correct the conditioned signal in speed corner estimation block as tracking input;

(2) by detecting current component i _d1obtain delay angle by phase-locked loop, be input in conditioned signal; To high-frequency current signal i _qhcarry out nursing one's health, rotating speed that the process such as filtering, PI estimation obtain permagnetic synchronous motor, position and d, q shaft current and then realize vector control, repeat step (1).

In conditioned signal, real-time tracking compensation is carried out to the delay angle that system produces.

Advantage and effect

Tool of the present invention has the following advantages and beneficial effect:

The present invention breaches in conventional highfrequency pulsating voltage injection method permagnetic synchronous motor vector control without position sensor system can accurately tracing motor rotation speed and position, the problem of control system instability, the present invention is in the vector control system of traditional pulsating high frequency signal injection method permagnetic synchronous motor position-sensor-free, consider filter time delay, and real-time tracking compensation is carried out to time delay angle, empirical tests adopts the vector control control technology of the pulsating high frequency signal injection method permagnetic synchronous motor position-sensor-free improved compared with traditional high frequency pulsating voltage injection method control technology, systematic steady state error improves greatly, stability is improved.

Accompanying drawing explanation

Fig. 1 improves high frequency pulsating voltage injection method permagnetic synchronous motor vector control without position sensor system construction drawing for adopting;

Fig. 2 is the structure and the flow chart that improve high frequency pulsating voltage injection method permagnetic synchronous motor vector control without position sensor.

Embodiment

Below in conjunction with accompanying drawing, the present invention is described further:

The present invention can be used in the vector control system of permagnetic synchronous motor position-sensor-free, the instability in permagnetic synchronous motor vector control without position sensor system can be solved well, the problem that steady-state error is large, invent delay angle real-Time Tracking Control device, be made up of original high-frequency current signal processing controller and additional delay angle tracing compensation controller, the conditioned signal that wherein conditioned signal adds by original ideal conditions the time delay angle that real-time tracking compensates is revised, reduce the velocity location evaluated error of permagnetic synchronous motor, the stability of whole system is improved.

The present invention is this based on PMSM low speed vector control without position sensor system, this system includes speed preset through vector control module and high frequency signal injection model calling to permagnetic synchronous motor, by being connected to vector control module to the current detecting filtering processing modules implement electric current loop closed loop of permanent-magnetic synchronous motor stator electric current, and then have current detecting filtering processing module to be connected to delay angle tracing compensation control module and speed, corner estimation module, the compensation of delay angle tracing compensation control module is connected to speed, corner estimation module, Negotiation speed, corner estimation module realizes speed closed loop.

The above-mentioned control method based on PMSM low speed vector control without position sensor system, have employed a kind of tracking compensation technique of novel tracking filter delay angle.

Based on improvement high frequency pulsating voltage permagnetic synchronous motor vector control without position sensor system as shown in Figure 1: inject high frequency sinusoidal voltage signal at d axle, the restituted signal cosw of the high-frequency current signal of electric current q axle and the pulsating high frequency voltage same frequency of injection detected in the stator terminal of permagnetic synchronous motor _hafter t is multiplied, obtain and comprise rotor position estimate control information, then device, PI estimate that the process of device obtains spinner velocity and positional information after filtering, our improvements are exactly consider the delay angle of system device to high-frequency current signal, measure at electric current d axle the delay angle caused, namely in figure, the tracking of delay angle is compensated in real time adjustment again and corrects restituted signal and be , achieve the rotating speed to better effect and location estimation.Its structure and control flow chart are as shown in Figure 2.Below in conjunction with Fig. 2 and formula, set forth process and the step based on improving pulsating high frequency signal injection method filter time delay angle tracking compensation:

The electric current be subject to from motor stator termination carries out coordinate transform, obtains high-frequency current signal in electric current q reference axis through high pass filter BSF, in consideration phase delay angle prerequisite under

In formula phase delay angle between the high-frequency current signal that the high-frequency voltage signal injected for voltage d reference axis and electric current q reference axis receive.As can be seen from formula (1), as position estimation error Δ θ _rwhen equaling constant, namely position estimation procedure terminates, and the amplitude of the high-frequency current signal on electric current reference axis q is also constant.Can be expressed as:

Formula (2) σ is constant amplitude.In the demodulating process of carrier signal, require restituted signal cos (w _ht) in phase place, keep synchronous with (2), namely we want accurate real-time tracking phase delay angle size.Simultaneously by the known rotor position estimate error delta θ of above formula _rhigh-frequency current component when being zero in q reference axis, also with regard to zero, does not obtain phase delay angle by the high-frequency current component in q reference axis thus.Can the high-frequency current component in q reference axis and the high-frequency current component phase place in d reference axis be synchronous, separate by emulation experiment.As evaluated error Δ θ _rwhen being zero, the high-frequency current component in d reference axis is non-vanishing, so we select the high-frequency current component i on reference axis d _dhfollow the tracks of delay angle, by the method for phase-locked loop by i _dhas input signal, come estimated delays angle size so that realize demodulation accurately.

$i_{\mathrm{dh}}=-\frac{j\·v_h\sin w_{h}t}{w_h{L}_{\mathrm{dh}}{L}_{\mathrm{qh}}}(L_{\mathrm{avg}}-L_{\mathrm{diff}}\cos 2\mathrm{\Δ}{\mathrm{\θ}}_r)---\left(3\right);$

As rotor position estimate error delta θ _rwhen being zero, (3) formula can change into:

$\begin{array}{c}{i}_{\mathrm{dh}}=-\frac{v_h\cos w_{h}t}{w_h{L}_{\mathrm{dh}}{L}_{\mathrm{qh}}}(L_{\mathrm{avg}}-L_{\mathrm{diff}})\\ =-\frac{v_h\cos w_{h}t}{w_h{L}_{\mathrm{dh}}}\end{array}---\left(4\right);$

Consider phase delay angle , the high-frequency current signal of d axle is:

Can proper site error Δ θ by (5) formula _rwhen being zero, the high-frequency current component of d reference axis is non-vanishing, can select i thus _dhestimate phase delay angle.

Phase-locked loop delay angle estimates strategy as shown in Figure 2, high-frequency current signal component i from reference axis d _dhbe multiplied with the sinusoidal signal of the same frequency injected and be shown below:

Can obtain ε by (6) formula result of calculation and comprise two components, one containing phase error low frequency component, another is two harmonics.In formula be phase meter error and phase estimation error respectively, we select low pass filter LPF to arrange appropriate frequency just can two harmonics in filtering ε, so can obtain:

In formula (7), δ is system constants, phase error _lPFinput signal and feedback signal phase difference function, follow the tracks of phase delay angle exactly just exporting through pi regulator, make equal.Modulation signal is compensated

High-frequency current component in q reference axis is multiplied with modulation signal and obtains rotor position estimation information

σ in (8) formula ₁for fixed constant, when rotor position estimate error is enough little, the input signal of PI estimator linearly can be changed, i.e. σ ₁sin2 Δ θ _r=σ ₂Δ θ _r, regulate suitable P, I parameter just can obtain the estimation of spinner velocity and position.The parameter of electric machine is selected to be as following table.

Parameter of electric machine table

Moment of inertia kgm 2	0.0008	Stator resistance Ω	2.8758
				D axle inductance mH	8.5	Q axle inductance mH	8.5
Permanent magnet flux linkage Wb	0.175	Number of pole-pairs	2

Carry out in empty load of motor given rotating speed 50rad/s situation through MATLAB emulation experiment.

The high frequency sinusoidal voltage signal magnitude injected is 3, and frequency is 800HZ.Through repeatedly debugging, with current i _dwith i _d2, i _qwith i _q2do difference and be respectively I:40, P:72.8 and I:11.5, P:2.2 as the PI parameter after input.The electric current low pass filter LPF upper cut-off frequency doing poor loop arranges 150HZ, and the cut-off frequency that rolls off the production line is 100HZ.Two band pass filter BSF upper cut-off frequency cut-off frequency 700HZ passbands, lower-cut-off frequency 900HZ.What rotating speed and rotor-position PI estimated device arranges P:500000I:1500, and PI estimates band stop filter BSF stopband upper cut off frequency 1700HZ, stopband lower-cut-off frequency 1500HZ before device input.The PI optimum configurations P:0.00005I:900 of delay angle Phase Tracking, the low pass filter upper cut-off frequency 800HZ lower-cut-off frequency 750HZ before its input, obtain through operating analysis and system can be made more accurate, stable.

Empirical tests records tracing compensation phase delay systematic steady state error brings up to 0.25% by 1.5%, and initial dynamic low cruise there will not be system wild effect, so use the high frequency voltage pulsating injection method improved to make the steady-state error of system cloud gray model and stability improve.

Claims (3)

1. one kind based on PMSM low speed vector control without position sensor system, it is characterized in that: this system includes speed preset through vector control module and high frequency signal injection model calling to permagnetic synchronous motor, by being connected to vector control module to the current detecting filtering processing modules implement electric current loop closed loop of permanent-magnetic synchronous motor stator electric current, and then be connected to delay angle tracing compensation control module and speed by current detecting filtering processing module, corner estimation module, the compensation of delay angle tracing compensation control module is connected to speed, corner estimation module, Negotiation speed, corner estimation module realizes speed closed loop.

2. one kind as claimed in claim 1 based on the control method of PMSM low speed vector control without position sensor system, it is characterized in that: the delay angle of the high-frequency voltage signal injected to the high-frequency current signal detected is carried out to real-time tracking and then realize real-Time Compensation, reach the operation of the minimum steady-state error of whole system, step is as follows:

(1) system is by the injection of high frequency pulsating voltage signal, by the i detecting permanent-magnetic synchronous motor stator side electric current _q1transform component, obtains motor speed, position by filter, phase-locked loop process; In signal condition process, need to detect the delay angle produced by system device correct the conditioned signal in speed corner estimation block as tracking input;

(2) by detecting current component i _d1obtain delay angle by phase-locked loop, be input in conditioned signal; To high-frequency current signal i _qhcarry out nursing one's health, rotating speed that the process such as filtering, PI estimation obtain permagnetic synchronous motor, position and d, q shaft current and then realize vector control, repeat step (1).

3. according to claim 2 based on PMSM low speed non-position sensor vector control method, it is characterized in that: in conditioned signal, real-time tracking compensation has been carried out to the delay angle that system produces.