Dynamic Voltage Restorer and Hybrid Active Power Filter for Power Quality Improvement: Comparative Study

Power quality means maintaining the voltage, current and power within the rating as per the IEC
standards and supplying it back to the consumers without any delay and interruption. But this has
become a difficult task for the power industry. To improve power quality many Custom Power Device’s
(CPD) are used. Dynamic Voltage Restorer (DVR) is a CPD which is used to improve the voltage
quality. Hybrid Active Power Filter (HAPF) is used to reduce current harmonics. In this chapter DVR
and HAPF are simulated for various conditions. A controller is proposed which gives voltage signals to
trigger the switches of an inverter using a Pulse Width Modulation (PWM) scheme. As a result, there
is drastic improvement in voltage profile and also reduction in harmonics.