Sliding mode observer for sensorless control of surface permanent magnet synchronous motor equipped with LC filter

Self Cite

In some cases, LC filters are installed between the inverters and motors to suppress the adverse effects of pulse width modulation. However, some techniques should be modified, because the mathematical model of the drive system is changed by the LC filter and the sensors on the inverter output cannot measure some necessary variables. In this study, a multipurpose proportional-integral (PI) observer is proposed at first. The type of observer depends on whether the position sensor is equipped. A sliding mode controller for the LC filter based on the observer is presented, therefore improving the dynamic performance. Furthermore, if the position sensor of the rotor is equipped, an open-switch fault diagnostic method is realised by means of the PI observer; if the position sensor is not equipped, the sensorless estimation is realized. The proposed strategies were realised without any additional current/voltage sensors. Experimental results verified the effectiveness of the proposed strategies.

Section: Introductionmentioning

confidence: 99%

Sliding mode control with open‐switch fault diagnosis and sensorless estimation based on PI observer for PMSM drive connected with an LC filter

Wang

Zou

2020

Self Cite

“…Permanent-magnet synchronous motors (PMSMs) can be used in the applications with high requirements to energy saving and performance due to its high power density, high efficiency, high reliability, and easily implemented field-weakening operations [1][2][3][4][5][6][7][8][9]. The high-performance control of PMSM requires accurate rotor position information.…”

Section: Introductionmentioning

confidence: 99%

“…Nevertheless, the deficiencies of conventional encoder or resolver in signal reliability, environmental adaptability, installation, maintenance, and cost debase the robustness, reliability, and product competitiveness of the drive system [2][3][4][5][6][7]. For these reasons, sensorless control technology was proposed and developed into a hot spot in the field of electric drive.…”

Section: Introductionmentioning

confidence: 99%

Comparative study of sensorless control of Permanent magnet synchronous motor realised by sliding‐mode observer

Chen

et al. 2020

In this study, the permanent-magnet synchronous motor sensorless control systems realised by sliding-mode observers in stationary αβ and estimated γδ coordinates are systematically studied and compared. First, based on the sufficient condition of sliding-mode stability, a more reasonable selection method of boundary layer width and sliding-mode gain is derived, effectively reducing the system chattering. Furthermore, in extracting estimated extended electromotive force, the advantages and disadvantages of the backforward method in the αβ-axis and the influence of filter cutoff frequency on estimation error in the γδ-axis are analysed. Finally, the estimation error, speed range, stability, and the effect of speed error of these two sensorless control systems are analysed and compared. The results indicate that these two systems have equivalent position error above a certain speed, and the γδ-axis estimation system has a larger position error in low-speed range, but still operating well. Moreover, the γδ-axis estimation algorithm has better stability and wider-speed range. Owing to the fast track of phase-locked loop, the effect of speed error on estimation accuracy of the γδ-axis system can be neglected. Simulation and experiment verified the theoretical analysis and comparison.

“…Position sensors' applications can enhance the cost of the system as well as decrease motors' robustness and reliability. Hence, sensorless control, which enables the system to avoid using position sensors, has become one hot research direction in the area of motor control [4][5][6].…”

Section: Introductionmentioning

confidence: 99%

Second‐order lead compensator‐based quadrature PLL for sensorless interior permanent magnet synchronous motor control

Chen

et al. 2020

To eliminate harmonic components in estimated speed and position information generated by inverter non-linearities for the interior permanent-magnet synchronous motor (IPMSM) sensorless control, a second-order lead compensator-based quadrature phase-locked loop (SOLC-Q-PLL) is proposed for the sliding mode observer. An adaptive super-twisting sliding mode observer is taken to estimate back electromotive forces (EMFs) for IPMSM. Harmonic components in estimated position information generated by inverter non-linearities are analysed. Being dependent on the corresponding analysis, the SOLC-Q-PLL is proposed to eliminate sixth position estimation errors only by introducing a second-order lead compensator without causing phase delay for the phase-locked loop system. The introduction of the second-order lead compensator does not influence the bandwidth of the phase-locked loop system so that a fast transient response can be achieved, and this algorithm is easy to implement digitally due to its simple structure. Eventually, a series of experiments are conducted to validate the capability of the proposed algorithm.