A. K. Panda

High performance direct torque and flux control of induction motor drive using fuzzy logic based speed controller

In this research study, direct torque and flux control of induction motor drive (IMD) using fuzzy logic control (FLC) based speed control loop (SCL) is proposed to minimize the ripple contents of stator current, flux and torque and also improve the speed response under transient and steady state operating conditions. It is quite difficult to optimize the high performance of an IMD using conventional PI-controller, because of the nonlinear model of induction motor drive. The PI-controller are requires accurate and continuous tuning of gain values. Therefore, the FLC technique is proposed to improve the system performance. The detailed simulation results are presented in forward and reversal motoring under 1200rpm with no-load, load and sudden change in speed operating conditions using MATLAB/Simulink software to support the feasibility of the proposed control strategy.

Sliding-mode and fuzzy logic control based MRAS speed estimators for sensorless direct torque and flux control of an induction motor drive

In this paper, a rotor-flux model reference adaptive system (MRAS) based speed sensorless direct torque and flux control (DTFC) of induction motor drive (IMD) using sliding-mode control (SMC) and fuzzy logic control (FLC) based adaptation mechanism schemes are implemented to replace the conventional constant gain PI-controller (PIC). The SMC is considered to minimize the error dynamics under different loading conditions, which is derived based on Lyapunov theorem. Furthermore, the FLC adaptation scheme is proposed to minimize the chattering phenomenon as well as achieve high performance speed sensorless drive with less error signal. The performance of each adaptation control schemes has been tested for its robustness to sudden change in speed and load disturbance. A detailed comparison of different control schemes are carried out in a MATALB/Simulink environment in both sensor and sensorless modes of operation, when a IMD is operating in forward and reversal motoring under no-load, load, sudden change in speed and sudden zero speed conditions.

Performance enhancement of the vector control based Permanent Magnet Synchronous Motor drive using hybrid PI-Fuzzy logic controller

Vector control principle makes the analysis and control of Permanent Magnet Synchronous Motor (PMSM) drives system simpler and provides better dynamic response. This paper manifest a simulation for speed control and improvement in the performance of a closed loop vector controlled Interior permanent magnet Synchronous Motor (IPMSM) drive which employ two loops for better speed tracking along with provides reduced torque ripple and fast dynamic response during dynamic as well as steady state conditions by controlling the torque component of current. The outer loop employing hybrid PI- Fuzzy logic controller (PI-FLC) with their superior functions designed for effective speed control under dynamic condition, while inner loop as adaptive hysteresis current controller designed to reduce the torque ripple. The complete proposed model is implemented and tested in the Matlab/Simulink environment and a performance of proposed method is compared with conventional PI and fuzzy logic controller. Comparing with the PI and FLC, the FLC-PI method has superior performance.

Type-1 and Type-2 fuzzy logic speed controller based high performance direct torque and flux controlled induction motor drive

In this research study, a new speed control scheme is proposed for direct torque and flux control (DTFC) of induction motor drive (IMD) to replace the conventional constant gain PI-speed controller (PISC). The conventional PISC offers poor dynamic response of stator current, torque and motor speed under sudden change in speed or load torque disturbances. In order to improve the dynamic as well as the steady state performance and minimize the ripple contents and also motor speed drops under load torque conditions, a new Mamdani type, triangular membership function (M.F) based Type-2 fuzzy logic speed controller (T2FLSC) is proposed, which is replaced in place of PISC. The proposed Type-2 FLSC is extension of Type-1 FLSC, which is very effectively control under sudden load torque disturbances and sudden change in speed conditions. A detailed simulation results are carried out when an IMD is operating in forward and reversal motoring under no-load, load, sudden change in speed and zero speed conditions.

DTFC-SVM for three-level diode clamped inverter fed IM drive

This paper presents a direct torque and flux control with space vector modulation (DTFC-SVM) for a three-level diode clamped inverter (3LDCI) fed induction motor drive (IMD) using proportional-Integral controller (PIC). Diode-clamped inverters are the most widely used topology of multilevel inverters in high-power applications. The DTFC-SVM of an IMD using two-level inverter (2LI) provides large ripple contents in torque, flux and stator currents. In order to reduce the ripple contents in torque, flux and stator currents, a 3LDCI based DTFC-SVM method is proposed. In order to show the effectiveness of the proposed method, it is simulated in a MATLAB/SIMULINK environment. The performance of the IMD is simulated under various operating conditions.

A ZVT-PWM multiphase synchronous buck converter with an active auxiliary circuit for portable applications

In this paper, a Zero-Voltage-Transition (ZVT) Pulse-width Modulated (PWM) multiphase synchronous buck converter (SBC), with an active auxiliary circuit is proposed, that reduces the stresses and enhances the efficiency abating the switching and conduction losses of the converter. The important design feature of ZVT-PWM multiphase SBC converters is placement of resonant components that pacifies the switching and conduction losses. Due to the ZVT, the resonant components with low values are used that results in the increase of switching frequency. High current multiphase buck converters found applications in advanced data control, portable applications and other applications like computer processors. The zero-voltage-transition operation of the proposed converter is presented through theoretical analysis. The characteristics of the proposed converter are verified with the simulation in the PSIM cosimulated with MATLAB/SIMULINK environment.

Artificial intelligence based high performance direct torque and flux control of induction motor drive

In this research study, direct torque and flux control of induction motor drive (IMD) using artificial intelligence based speed control loop (SCL) to minimize the ripple contents of the stator current, flux and electromagnetic torque, and also improving the speed response under transient and steady state conditions. It is quite difficult to optimize the high performance of DTC of IMD with conventional (PI-controller) scheme, because of the nonlinear model of induction motor. This system requires accurate and continuous tuning of gain values. Therefore, the fuzzy logic controller (FLC) and PI-FLC techniques are proposed to improve the system performance. The detailed simulation results are presented in forward motoring under no-load, load and sudden change in speed conditions using MATLAB/Simulink software to support the feasibility of the proposed control strategy.

A simple passive auxiliary circuit for reduction of losses and efficiency enhancement of synchronous buck converter

In this paper, a Zero-Voltage-Transition (ZVT) Pulsewidth Modulated (PWM) synchronous buck converter (SBC), with a simple passive auxiliary circuit is proposed, which reduces the stresses and improves the efficiency by pacifying the conduction losses compared to a traditional PWM converter, typically suitable for photovoltaic applications. The important design feature of ZVT-PWM SBC converters is placement of resonant components that mollifies the conduction losses. Due to the ZVT, the resonant components with low values are used thereby resulting in the increase of switching frequency. The zero-voltage-transition operation of the proposed converter is presented through theoretical analysis. The characteristics of the proposed converter are verified with the simulation in the PSIM cosimulated with MATLAB/SIMULINK environment.