Transcript 下載/瀏覽

Robot and Servo Drive Lab.
Sensorless Control Method for PMSM Based on
Frequency-Adaptive Disturbance Observer
IEEE JOURNAL OF EMERGING AND SELECTED TOPICS IN POWER
ELECTRONICS, VOL. 2, NO. 2, JUNE 2014
Yongsoon Park, Student Member, IEEE, and Seung-Ki Sul, Fellow, IEEE
學
生:林信佑
指導教授:王明賢
Department of Electrical Engineering
Southern Taiwan University of Science and Technology
2016/7/12
outline







Abstract
Introduction
DISTURBANCE OBSERVER FOR FLUX ESTIMATION
Gain Settings of the Disturbance Observer
Experiments
Conclusion
References
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
2
Abstract


In this paper, a frequency-adaptive disturbance observer has
been proposed to remove the disturbances in estimating the
stator flux and to enhance the accuracy of the rotor angle
estimation.
The performance of the proposed sensorless method has been
mainly assessed through experiments at low speed operations,
where the sensorless drive of PMSM is regarded as being
extremely difficult without the signal injection.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
3
Introduction



FOR HIGH performance servo drive, the rotor angle of
permanent magnet synchronous motor (PMSM) should be
detected without time delay.
The rotor angle indicates the direction of rotor flux originated
from the permanent magnet, and the position sensor is
normally used to detect it.
However, the position sensor may cause some problems
related to extended axial length, extra cost, reliability concern,
and electromagnetic interference of signal.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
4



In general, the estimation of stator flux is based on (1)
which is derived from the stator voltage equation in (2)
Rs is the stator resistance, λ f refers to the flux linkage of
permanent magnet, and θr to the rotor angle.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
5

The stator flux can be calculated through integration according
to (1), which is based on (2). When considering the current
model in (1) with (3), the stator flux in the stationary reference
frame can be described as
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
6
T2S for the estimation of angle and speed

If λem is always positive under operation, (6) can be used to
calculate the rotor angle.For the most cases of PMSM, λem
may have positive value even with the maximum id .
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
7
State Equation to Design the Disturbance
Observer


When λm refers to the magnitude of stator flux in the α−β
frame, the stator flux estimated by the integration in a practical
system can be modeled as
Disturbances are mainly low-frequency phenomenon, which
can be modeled by step signal model [22]. In addition, if λm is
also assumed to be step varying, the derivative of (7) can be
derived as
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
8

where ω f means the rotating speed of stator flux. Based on
(8), the state equation on the estimated stator flux can be
derived as
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
9
Luenberger observe can be designed as

The hat “∧” indicates estimated value hereafter, and the
variables in Lm are the observer gains.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
10
Gain Settings of the Disturbance Observer

For the gain settings, the internal transfer functions of the
observer can be discussed. These transfer functions are derived
as (11), as explained in [16]
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
11
Gain Settings of the Disturbance Observer
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
12
Gain Settings of the Disturbance Observer
Pt=det[SIm-Am+LmCm]

2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
13

By the setting of (14), ω f only appears as the form of its
square in the coefficients of the internal transfer functions.
That is, the poles and zeros at a certain speed are the same
with those at the reversed speed. Then, the observer poles can
be placed by considering the positive case only. In addition,
the condition of (15) can be adopted to make the observer
structure symmetric in the α − β frame
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
14
The observer gains are finally determined as

When the gains in (16) are used, the transfer functions
pertaining to the disturbances are derived as
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
15
Disturbance Observer for Stator Flux
Estimation
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
16
Frequency response of proposed observer when
ω f is 2π10 rad/s.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
17
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
18
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
19
EXPERIMENTS

Initially, the rotor angle is directly calculated from the stator
flux by using (6) and (20) that is indicated by θˆr in Fig. 6.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
20
Equation (25) can be derived from (24)

2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
21
EXPERIMENTS

where the ratings of the eight-pole SMPMSM are 11.5 N-m
and 1500 r/min. The induction machine (IM) in Fig. 8(a) was
employed to apply load torque to the SMPMSM during
driving.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
22
EXPERIMENTS
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
23
EXPERIMENTS

The angle error θd was <0.25 rad near zero speed as shown in
Fig. 13.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
24
EXPERIMENTS

As explained earlier, the SMPMSM cannot be stopped
indefinitely at standstill under heavy loads with the proposed
method. However, as shown in Fig. 14, it has been confirmed
that the test motor can be repeatedly stayed at standstill for 300
ms under 7.5-N-m load, which corresponds to 65.2% of the
rated torque.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
25
Conclusion


The frequency-adaptive disturbance observer has been
proposedin this paper to enhance the performance of the
sensorless control method based on the stator flux model of
PMSM.
Although the proposed method could not ensure its
performance over all operating conditions, the speed of the test
motor could be repeatedly reversed by the proposed method
less than ±10% of its rated speed under 65.2% load. And,the
test motor can stay at zero speed with partial load without
instability issues for several hundred milliseconds.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
26
References





[1] Y.-D. Yoon, S.-K. Sul, S. Morimoto, and K. Ide, “High-bandwidth sensorless
algorithm for AC machines based on square-wave-type voltage injection,” IEEE
Trans. Ind. Appl., vol. 47, no. 3, pp. 1361–1370,May/Jun. 2011.
[2] J. Holtz, “Sensorless control of induction machines—With or without signal
injection,” IEEE Trans. Ind. Electron., vol. 53, no. 1, pp. 7–30,Feb. 2006.
[3] M. Schroedl, “Sensorless control of AC machines at low speed and standstill
based on the ‘INFORM’ method,” in Proc. Ind. Appl. Conf.31st IAS Annu. Meeting,
vol. 1. Oct. 1996, pp. 270–277.
[4] P. L. Jansen and R. D. Lorenz, “Transducer less position and velocity estimation
in introduction and salient AC machines,” IEEE Trans. Ind.Appl., vol. 31, no. 2, pp.
240–247, Mar./Apr. 1995.
[5] M. Linke, R. Kennel, and J. Holtz, “Sensorless position control of permanent
magnet synchronous machines without limitation at zero speed,” in Proc. 28th
Annu. Conf. Ind. Electron. Soc., Nov. 2002,pp. 674–679.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
27
References




[6] Z. Q. Zhu and L. M. Gong, “Investigation of effectiveness of sensorless
operation in carrier-signal-injection-based sensorless-control methods,” IEEE
Trans. Ind. Electron., vol. 58, no. 8, pp. 3431–3439, Aug. 2011.
[7] R. Mizutani, T. Takeshita, and N. Matsui, “Current model-based sensorless
drives of salient-pole PMSM at low speed and standstill,” IEEE Trans. Ind. Appl.,
vol. 34, no. 4, pp. 841–846, Jul./Aug. 1998.
[8] S. Morimoto, K. Kawamoto, M. Sanada, and Y. Takeda, “Sensorless control
strategy for salient-pole PMSM based on extended EMF in rotating reference
frame,” IEEE Trans. Ind. Appl., vol. 38, no. 4, pp. 1054–1061, Jul./Aug. 2002.
[9] P. Kshirsagar, R. P. Burgos, J. Jang, A. Lidozzi, F. Wang, D. Boroyevich, et al.,
“Implementation and sensorless vector-control design and tuning strategy for
SMPM machines in fan-type applications,” IEEE Trans. Ind. Appl., vol. 48, no. 6,
pp. 2402–2413, Nov./Dec. 2012.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
28
References





[10] K.-W. Lee and J.-I. Ha, “Evaluation of back-EMF estimators for sensorless
control of permanent magnet synchronous motors,” J. Power Electron., vol. 12, no.
4, pp. 604–614, Jul. 2012.
[11] A. Khlaief, M. Bendjedia, M. Boussak, and M. Gossa, “A nonlinear observer
for high-performance sensorless speed control of IPMSM drive,” IEEE Trans.
Power Electron., vol. 27, no. 6, pp. 3028–3040,Jun. 2012.
[12] I. Boldea, M. C. Paicu, and G.-D. Andreescu, “Active flux concept for motionsensorless unified AC drives,” IEEE Trans. Power Electron., vol. 23, no. 5, pp.
2612–2618, Sep. 2008.
[13] G. Foo and M. F. Rahman, “Sensorless direct torque and flux-controlled IPM
synchronous motor drive at very low speed without signal injection,” IEEE Trans.
Ind. Electron., vol. 57, no. 1, pp. 395–403, Jan. 2010.
[14] Y. Park, S.-K. Sul, J.-K. Ji, and Y.-J. Park, “Analysis of estimation errors in
rotor position for a sensorless control system using a PMSM,” J. Power Electron.,
vol. 12, no. 5, pp. 748–757, Sep. 2012.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
29
References





[15] D. G. Luenberger, “An introduction to observers,” IEEE Trans. Autom.
Control, vol. 16, no. 6, pp. 596–602, Dec. 1971.
[16] Y. Park, S.-K. Sul, W.-C. Kim, and H.-Y. Lee, “Phase locked loop based on an
observer for grid synchronization,” in Proc. IEEE 28th APEC, Mar. 2013, pp. 308–
315.
[17] Y.-C. Son, B.-H. Bae, and S.-K. Sul, “Sensorless operation of permanent
magnet motor using direct voltage sensing circuit,” in Proc. Conf. Rec. IEEE IAS
Annu. Meeting, Oct. 2002, pp. 1674–1678.
18] B.-H. Bae and S.-K. Sul, “A compensation method for time delay of full-digital
synchronous frame current regulator of PWM AC drives,” IEEE Trans. Ind. Appl.,
vol. 39, no. 3, pp. 802–810, May/Jun. 2003.
[19] Y. Park and S.-K. Sul, “A novel method utilizing trapezoidal voltage to
compensate for inverter nonlinearity,” IEEE Trans. Power Electron., vol. 27, no.
12, pp. 4837–4846, Dec. 2012.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
30
References





[20] Y. Park and S.-K. Sul, “Compensation of inverter nonlinearity based on
trapezoidal voltage,” in Proc. IEEE ECCE, Sep. 2012, pp. 2292–2299.
[21] D.-W. Chung, J.-S. Kim, and S.-K. Sul, “Unified voltage modulation technique
for real-time three-phase power conversion,” IEEE Trans. Ind. Appl., vol. 34, no. 2,
pp. 374–380, Mar./Apr. 1998.
[22] M. A. Johnson and M. H. Moradi, “Some PID control fundamentals,” in PID
Control: New Identification and Design Methods. New York, NY, USA: SpringerVerlag, 2005, ch. 2.
[23] Y. Peng, D. Vrancic, and R. Hanus, “Anti-windup, bumpless, and conditioned
transfer techniques for PID controllers,” IEEE Control Syst., vol. 16, no. 4, pp. 48–
57, Aug. 1996.
[24] J.-P. Lee, B.-D. Min, T.-J. Kim, D.-W. Yoo, and J.-Y. Yoo, “Active frequency
with a positive feedback anti-islanding method based on a robust PLL algorithm for
grid-connected PV PCS,” J. Power Electron., vol. 11, no. 3, pp. 360–368, May
2011.
2016/7/12
Department of Electrical Engineering
Robot and Servo Drive Lab.
Southern Taiwan University of Science and Technology
31