Transient Vector Estimator Based High Dynamic Performance Control and Kalman Filter based Self Commissioning of Induction Motor Drives for Electric Vehicle Applications

Abstract

Induction machine, the work horse of the industry, has been widely used in industrial drives. The most common and efficient way to control the speed of induction machine is with variable frequency drives. The variable frequency drive schemes can be classiffied as scalar and vector control methods. Scalar control, which is based on the steady state ma- chine model, is a simpler and cost-effective way to control the speed of induction machine. Using scalar control, the amplitude and frequency of stator voltage are controlled with- out phase control, resulting in its poor dynamic response. This limits the usage of scalar control to the applications that do not require faster response. The advantage of scalar control is that it is not sensitive to the variation in machine parameters. In contrast to this, vector control that is based on the dynamic machine model, allows the independent control of torque and ux. The amplitude, frequency and phase of the stator voltage are controlled in vector control. The torque response in vector control is much faster when compared to that of scalar control techniques. However, vector control techniques are sensitive to the variation in machine parameters. Slip estimated in vector control scheme depends on the rotor resistance, rotor leakage and mutual inductances. Thus, either inaccurate estimation or variation in these parameters can lead to the incorrect estimation of slip, that results in the incorrect value of synchronous speed. This can lead to the degradation in the performance of vector control. A novel speed control scheme, that includes the advantageous features of both scalar and vector control schemes, is proposed. The proposed scheme provides good transient performance, while retaining the robustness aspects of scalar control. Scalar control acts as steady state platform in the proposed method. The transient response is improved by employing phase control of stator voltage as well...