T.S. Electrical
Works
Works
The dynamic voltage restorer (DVR) recognises and compensates for distortions in the voltage of the AC power source so that the loads are protected from these power safety issues. The operating policy for the DVR is illustrated in Fig. 17.3 [3]. The DVR consists of DC energy sources, an IGBT converter, and an injection transformer which is attached in series with the power line and the sensitive part. The DC power sources that can be applied are batteries, supercapacitors, superconducting fascinating storage systems, and flywheels. A fall in the input AC power line voltage may develop through the power system due to a fault in one of the distribution feeder lines. The DVR recognises the sag and generates AC power from the DC power source by using the IGBT converter. The produced power is fed to the line by the transformer to adjust the sag so that the fine load takes a very good AC input power.
Generators will have automated voltage regulators to support the voltage as the pressure on the generator changes. The DVR-2000 is an electronic, solid-state, microprocessor-based controller device it controls the output voltage of a brushless ac generator by regulating the current into the generator exciter area. The solid-state system is the functional equivalent of the old electromechanical system which was the first AVR for generators. This is a feedback control system that regulates the output voltage of the generator, associates it with a set point and generates a signal that is used to improve the excitation of the generator. As the excitation flow in the winding of the generator builds its terminal voltage will also improve.
