Digital signal processor based implementation of custom power device controllers

Custom power can be explained as the power supplied to the customers who do not tolerate any power quality problems that may occur in supplied power using custom power devices. Dynamic Voltage Restorer (DVR) is one of the custom power devices that is connected in series to the system. DVR detects the voltage sags and injects missing portion of voltage to the load. By this way, the load is not affected by voltage sags on the supply. Another custom power device is the Static Transfer Switch (STS) that transfers the supply of the voltage sensitive loads of customers who have two different feeders. When a sag or interruption occurs on one of the feeders, the loads are transferred to the healthy feeder in the shortest time possible. Shunt Active Power Filter (SAPF) is used to eliminate the current harmonics. The purpose of SAPF is to minimize the harmonic level of the source current by generating the harmonics required by the non-linear loads.Power electronics switching devices are widely used in the realization of custom power devices such as DVR, STS and SAPF. To control the power electronic equipments, controller design and development are needed. In this study, the controllers of DVR, STS and SAPF are designed, developed and implemented using Digital Signal Processors (DSP). A new sag detection and voltage compensation method is proposed for the DVR. The sag detection algorithms are also applied to the control of STS. In the implementation of SAPF, the problems caused by the voltage unbalance in instantenous reactive power method are solved. The design of custom power devices are explained in detail. Control algorithms and codes developed are presented.