Improved sliding mode control for permanent magnet synchronous motor servo system

In the direct drive motion system, there are obvious feedback harmonics caused by the various disturbances, which have important influence on the thrust characteristics of the permanent magnet synchronous linear motor (PMSLM). This paper presents the influence of the feedback harmonics on the detent force for the direct drive motion system. Firstly, the Maxwell's equation and the Schwarz–Christoffel (SC) mapping‐based method are used to accurately establish the magnetic field model in the air‐gap considering the slotting effect and end effect. Then, based on the control model of the motion system, the drive current caused by the feedback harmonics are calculated considering the non‐linearity of the drive circuit. The detent force of PMSLM is analytically represented and analyzed. Finally, the validity of the theoretical analysis is verified by the finite‐element method (FEM) and experiments. The results shown that the feedback harmonics will be coupled with the detent force and intensify the couplings among different sources of the thrust harmonics, which will lead to new coupled thrust harmonics, deteriorating the dynamic precision of the direct drive motion system.

Section: Analytical Prediction and Analysis Of The Detent Forcementioning

confidence: 99%

“…The detent force produced by the end effect can be improved by auxiliary poles [12,13]. In addition, lots of compensation method are produced to improve the influence of the detent force [14][15][16][17][18].…”

Section: Introductionmentioning

confidence: 99%

Analytical prediction and analysis of the detent force with the feedback harmonics for the direct drive motion system

Yang

Shi

Xuan

et al. 2023

“…A fuzzy control method was introduced to adjust the gain of SMC in real-time in ref. [16]. Besides, an adaptive sliding mode controller (ASMC) was designed to estimate the switching gain using an adaptive law to reduce system chattering caused by a fixed switching gain in ref.…”

Section: Introductionmentioning

confidence: 99%

ASMADO‐based refined anti‐disturbance low‐speed control of PMSM

Wang

Tong

Wang

et al. 2023

Permanent magnet synchronous motors (PMSMs) have expectant low‐speed servo performance. However, complex nonlinear disturbances restrict the performance and lead to speed fluctuations, especially for small inertia PMSMs where the current‐loop cannot be used in special operating conditions. This paper divides complex disturbances into periodic determinable disturbances and other indeterminate disturbances according to their characteristics. A refined anti‐disturbance control (RADC) method is proposed to enable the inner loop to compensate for disturbances in targeted manners. Then ideal low‐speed servo can be achieved using a simple outer loop controller. The proposed RADC consists of two parts. One is a backpropagation neural network based periodic disturbances compensator that is trained using the data from an iterative learning controller. The other is an adaptive sliding‐mode‐assisted disturbance observer that rapidly observes and compensates the residual disturbances. The convergence of the overall algorithm is analyzed. The effectiveness of the proposal is also verified by experiments.

“…In [15], a wavelet-neural-network-based H ∞ position tracking controller is proposed to overcome the system uncertainties. In [16], a new SMC method is introduced combined with a linear active disturbance rejection control strategy. Besides, a number of model-based control schemes are proposed to improve control accuracy and dynamic response of servo systems [17][18][19].…”

Section: Introductionmentioning

confidence: 99%

Adaptive control schemes based on characteristic model for servo motor drives

Wang

Wei

Fang

et al. 2023

In the paper, two adaptive control schemes based on characteristic model (CM) method are proposed to achieve great dynamic performance for servo motor drive applications. Two second‐order CMs of permanent magnet synchronous motors (PMSMs) are established based on the difference equation method. An adaptive controller consisting of four control laws is designed based on CMs. The proposed controller implements an improved maintaining/tracking control law that considers load torque ripple, plus a golden‐section adaptive control law, a logic differential control law, and a logic integral control law. In addition, two different servo systems using adaptive controllers are established, both of which are simple to implement and can achieve accurate position‐tracking or speed‐tracking in a servo drive system. The feasibility and effectiveness of the proposed adaptive control schemes are experimentally tested and verified on a servo motor drive platform.