Abstracto

Compensation of Long Term Voltage Fluctuations Using DVR with SMES

Jyothi Zachariah, Jo Joy

Now a days power grid has been experiencing several disturbances in electric power generation, transmission, and distribution. Changing electric load and higher power transfer in a wide interconnected network leads to serious, security lack in power system operation. As energy storage appears to be beneficial to utilities since it can coordinate the instantaneous balance between demand and supply. Today, there is a demand for short term energy storage devices like flywheel energy storage, photovoltaic modules, battery energy storage and super capacitors. Since they are having less power and energy rating, they cannot be used for high power applications. So in order to minimize this problem, SMES has been used to improve power system performance as well as power quality as it has having high power rating with maximum efficiency. Super conducting magnetic energy storage (SMES) based dynamic voltage restorer (DVR) is introduced to protect consumers from the grid voltage fluctuations. Due to its high energy density and quick response, its is selected as the energy storage unit to improve the compensation capability of DVR. The operation principle of the SMES based DVR, and design of the DVR control method are explained here. In normal DVR based compensation, downstream fault current was not considered or the DVR was bypassed during that fault. But here along with voltage sag compensation, downstream fault current mitigation was also considered.Using MATLAB, the SMES based DVR is modelled, and the simulation tests are carried out to evaluate the system performance.