IGBT based Static Voltage Stabilizer

Abstract

In electrical power system, due to continuous variation in load, it is not possible always to maintain the supply voltage at a nominal value. If the change in voltage is minor, it may not create problems to the connected load, but if variation of the voltage is beyond the permissible limit, it creates power quality issues. Generally for household (low and medium power) application, voltage stabilizer is the viable solution of this problem. The voltage stabilizer can be servo voltage stabilizer, relay based stabilizer and constant voltage transformer etc. Due to various limitations in the above mentioned stabilizers, static voltage stabilizers (using power semiconductor switches) have become more popular than the conventional stabilizers. The static voltage stabilizer is simple in design, less expensive, maximum range of voltage control and compact in size due to elimination of auto transformer. In this thesis a novel technique has been proposed to design and implement single phase static voltage stabilizer using controller. PIC 16F1936 controller has been used to generate the necessary control signal for IGBT modules. An IGBT based voltage stabilizer, which adopts high frequency PWM switching techniques and also regulates the voltage in wide range of supply fluctuation. The attractiveness of this configuration is that sinusoidal pulse width modulation (SPWM) pulses can be generated using this controller. Hence the pulses are used to produce pure sinusoidal wave of output voltage and current. The simulation validation has been done in simulate software and hardware based validation of the proposed scheme has been implemented.