Generalized Proportional Integral Observer Based Sliding Mode
Control Method for PMSM Speed Regulation System
Huiming Wang
1
, Shihua Li
1
, Hairong Zhu
2
, Shuoyan He
1
1. School of Automation, Southeast University, Nanjing 210096, P.R. China,
Key Laboratory of Measurement and Control of CSE, Ministry of Education
E-mail: whm613@163.com; lsh@seu.edu.cn; yanyanho@126.com
2. School of Electrical Engineering, Nantong University, Nantong 226019, P.R. China
E-mail: zhu.hr@ntu.edu.cn
Abstract: In this paper, we discuss the speed regulation problem of permanent magnet synchronous motor (PMSM)
system under unknown time-varying disturbances. Firstly, considering system disturbances, which generally include
model uncertainties and external disturbances, as lumped time-varying disturbances, it is estimated by a generalized
proportional integral (GPI) observer. Secondly, combining disturbances estimation and continuous sliding mode control
(SMC) method, a composite sliding mode control method, called the SMC+GPI method, is obtained for the speed
loop of PMSM system. Compared with conventional sliding mode control technique, the proposed method completely
eliminates chattering phenomenon caused by switching function in control law. Also, by feed-forward compensating
the estimated value of system disturbances, the disturbance rejection capability of continuous SMC method is enhanced
largely. simulation results are provided to demonstrate the superior properties of the proposed control method.
Key Words: Chattering free, Speed regulation, Permanent magnet synchronous motor (PMSM), Generalized propor-
tional integral (GPI) observer
1 INTRODUCTION
With the advantages of simple and easy to implement,
proportional-integral-derivative (PID) control scheme has
been widely used in permanent magnet synchronous motor
systems [1]. However, it is well known that PMSM, exist
unknown time-varying disturbances and parametric uncer-
tainties, is a nonlinear system, it is difficult to achieve a
high performance for PMSM system only by the tradition-
al linear control methods. Hence, nonlinear control algo-
rithms become a popular solution and have been success-
fully applied to PMSM system. such as robust control [4],
disturbance observer-based (DOB) control [5], finite time
control [6], sliding mode control [7] and adaptive control
[2], [3]. These nonlinear control methods have improved
the control performance of the PMSM system from differ-
ent aspects.
Due to the advantage of strong robustness against unknown
system disturbances and parameter uncertainties and sim-
plicity of both tuning and implementation, sliding mod-
e control (SMC) has received attention increasingly [8].
However, chattering phenomenon, which is caused by dis-
continuous control action that is adopted in sliding mode
This work is supported by National Natural Science Foundation of
China (61473080, 51307089), Science Foundation for Distinguished Y-
oung Scholars of Jiangsu Province (BK20130018), High-level Talents
Program in Six Industries of Jiangsu Province (DZXX-30), Fundamental
Research Funds for the Central Universities and Graduate Innovation Pro-
gram in Jiangsu Province (SJLX-0083), Open Project for Key Laboratory
of Complex Measurement in Ministry of Education (MCCSE2014A02), A
Project Funded by the Priority Academic Program Development of Jiang-
su Higher Education Institutions.
control law, is the main limitation of conventional SMC in
application. To this end, many elegant methods have been
proposed to reduce or eliminate the effect of chattering.
One effective method is to select a suitable switching gain
for the sliding mode control law because unsuitably large
switching gain leads to large chattering. A disturbance
observer-based technique is proposed in [9] to estimate sys-
tem disturbances and simultaneously deliver disturbances
estimation to the controller for on-line compensation. More
literature about this approach can be found in [10], [11].
Based on this method, the switching gain of sliding mode
controller can be selected a smaller value to reduce chat-
tering. These observer based control methods can estimate
the constant disturbance effectively, but is not professional
to handle time-varying disturbances. Moreover, the control
law is still discontinuous. Another effective method to re-
duce the chattering phenomenon is to design a continuous
control law. The boundary layer approach [12] is to elim-
inate the chattering phenomenon completely by means of
replacing the discontinuous control law with a continuous
one, but the performance of disturbance rejection is sacri-
ficed to some extent. In [13], a continuous SMC method is
proposed by designing the high frequency switching con-
trol into the higher derivative of the sliding variable, this
control technique can eliminate the chattering. According
to the above analysis, it is of great importance to develop
a continuous anti-disturbances control method for PMSM
system in the presence of time-varying disturbances.
In this paper, we first consider the disturbances of PMSM
system as unknown bounded time-varying disturbances
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2015 IEEE