In this paper various technique are describe for sensorless speed control of permanent magnet synchronous motor (PMSM). For low and medium power range PMSM play important role in motion control application in industry. Such application needs position and speed controllers with high accuracy, fast dynamical response and efficiency in the design process and implementation. In this paper various sensorless control techniques are reviewed and recent developments in this area are introduced with their inherent advantage and drawbacks.

Various techniques of sensorless speed control of PMSM: A review

The sliding mode observer is a very promising approach for position sensorless control of Permanent Magnet Synchronous Motors due to its robustness and parameter insensitivity. However it was observed that estimation of rotor flux position was affected due to measurement noise and phase shift introduced due to low pass filtering. In this paper, the authors discuss key issues related to implementation of sliding mode observer based sensorless field oriented control of Permanent Magnet Synchronous Motor and propose different approaches to improve rotor flux estimation. An experimental lab setup is designed and implemented on a 400W PMSM motor. Texas Instrument's TMS320F2812 DSP is used in the drive as the central controller to fulfill the demands of exhaustive real time computations by vector control and sliding mode observer.

Implementation issues of sliding mode observer for sensorless field oriented control of PMSM using TMS320F2812

In the recent years many researchers have focused on the sensor-less PMSM drive technology, wherein, estimators are used to estimate rotor position and speed using line current measurement. EKF is a powerful tool for such an application. However, implementation of EKF based sensor-less control needs measurement of torque for faithful mathematical model [1], which hinders practical application of the scheme. In this paper, a scheme with load torque estimation using Non Linear Disturbance Observer (NLDO) [2] in cascade with EKF to eliminate load torque sensor is proposed. With this, the proposed sensor-less scheme eliminates position sensor as well as a torque sensor.

Disturbance observer based sensor-less vector control drive for PMSM using EKF

In the recent past, the use of permanent magnet synchronous motors (PMSM) has increased due to the numerous advantages they offer. The accurate performance and precise speed and/or position control of a PMS motor requires precise information about the rotor shaft position and angular speed in order to synchronize the phase excitation pulses to the rotor position. In order to achieve the speed control various sensored methods are employed. Due to number of advantages, recent trend is to implement the sensorless drive for a PMSM. This paper presents the survey conducted in studying and understanding various methodologies of EKF based sensorless algorithms for the vector control drive of a PMSM.

Survey of EKF based sensorless vector control methodologies for a permanent magnet synchronous motor

Fuel cell is a promising electric vehicle power supply, but has disadvantages of poor dynamic performance and short service life. To solve the disadvantage, a method of hybrid power supply of fuel cell and super capacitor is adopted in the dynamic process, the super capacitor helps fuel cell enter the steady state. In this paper, the topology of the whole system is introduced, which use two DC/DC converters, one inverter and other subordinate devices. A ZVS-PWM-Unidirectional-DC/DC converter is used to realize the boost process of fuel cell. Interleaved-half-bridge-bidirectional DC/DC converter is used to realize power supply compensation of super capacitor and to realize recycle process of motor braking energy. DC bus is necessary because the inverter requires pulse current with SVPWM modulation method. The permanent magnet synchronous motor vector control strategy is adopted. In the strategy the inverter and the motor are integrated and controlled as a whole. The performance of the motor is satisfying for applications in the field of electric vehicles. Traditional cars lose a lot of energy in the process of braking. In order to increase energy utilization, regenerative braking energy is recycled by super capacitor. In this paper, a new energy control strategy for dual closed-loop dual power supply with filters is proposed. The feasibility of the system and the control strategy are verified by MATLAB simulation preliminarily.

Research on energy management system of hybrid electric vehicle based on permanent magnet synchronous motor

In the recent past, the use of permanent magnet synchronous motors (PMSM) has increased considerably owing to their inherent advantages. The high performance speed and/or position control of a PMS motor requires an accurate knowledge of rotor shaft position and angular speed in order to synchronize the phase excitation pulses to the rotor position. The rotor position and speed information is specifically required for implementation of vector control scheme in a PMSM. In order to achieve the speed control various sensored methods are employed. Due to number of advantages recent trend is to implement the sensorless control drive for a PMSM. This paper presents and compares two main sensorless control algorithms viz, Sliding Mode observer(SMO) and Extended Kalman Filter (EKF) for sensorless estimation of rotor position and speed in a PMSM. The simulation results for both these methods on an identical PMSM are presented. The analysis of these results give some insights into the accuracy of estimations and subsequent working of the PMSM with them.

Jayawant P. Kolhe

Papers

Study of sensorless control algorithms for a permanent magnet synchronous motor vector control drive