The effectiveness of a combination of fault current limiter and thyristor controlled braking resistor on power system stability enhancement and damping turbine shaft torsional oscillations has been studied. If both de...The effectiveness of a combination of fault current limiter and thyristor controlled braking resistor on power system stability enhancement and damping turbine shaft torsional oscillations has been studied. If both devices operate at the same bus, the stabilization control scheme can be carried out continuously and with flexibility. As a result, the fault currents are limited, and the generator disturbances and the turbine shaft torsional oscillations are converged quickly. In this paper, the effectiveness of the combination of both devices has been demonstrated by considering 3LG (three-lines-to-ground) fault in a two-machine infinite bus system. Also, temperature rise effect of both devices with various resistance values and weights has been demonstrated. Simulation results indicate a significant power system stability enhancement and damping turbine shaft torsional oscillations as well as with allowable temperature rise.展开更多
This paper presents a sliding mode observer for sensorless operation of SRM (switched reluctance motor) drive. Design of such an observer depends mainly on the nonlinear model of SRM. In this technique, neither extr...This paper presents a sliding mode observer for sensorless operation of SRM (switched reluctance motor) drive. Design of such an observer depends mainly on the nonlinear model of SRM. In this technique, neither extra hardware nor huge memory space are not required but it only requires active phase measurements. Furthermore, PI (proportional integral) and adaptive FLPI (fuzzy logic PI) controllers are suggested to operate individually along with the SMO (sliding mode observer) to cover a full speed range of sensorless controller. Both controller schemes operate in PWM (pulse width modulation) control mode. The proposed observer is implemented and tested using a digital signal processor. All results obtained with both simulation and experimental investigations corroborate the superior performance of the adaptive fuzzy logic controller (FLPI) when compared with those of PI controller.展开更多
文摘The effectiveness of a combination of fault current limiter and thyristor controlled braking resistor on power system stability enhancement and damping turbine shaft torsional oscillations has been studied. If both devices operate at the same bus, the stabilization control scheme can be carried out continuously and with flexibility. As a result, the fault currents are limited, and the generator disturbances and the turbine shaft torsional oscillations are converged quickly. In this paper, the effectiveness of the combination of both devices has been demonstrated by considering 3LG (three-lines-to-ground) fault in a two-machine infinite bus system. Also, temperature rise effect of both devices with various resistance values and weights has been demonstrated. Simulation results indicate a significant power system stability enhancement and damping turbine shaft torsional oscillations as well as with allowable temperature rise.
文摘This paper presents a sliding mode observer for sensorless operation of SRM (switched reluctance motor) drive. Design of such an observer depends mainly on the nonlinear model of SRM. In this technique, neither extra hardware nor huge memory space are not required but it only requires active phase measurements. Furthermore, PI (proportional integral) and adaptive FLPI (fuzzy logic PI) controllers are suggested to operate individually along with the SMO (sliding mode observer) to cover a full speed range of sensorless controller. Both controller schemes operate in PWM (pulse width modulation) control mode. The proposed observer is implemented and tested using a digital signal processor. All results obtained with both simulation and experimental investigations corroborate the superior performance of the adaptive fuzzy logic controller (FLPI) when compared with those of PI controller.