Integration of the premium power supply on electric power system

This paper describes an inverter-interfaced distributed generation (DG) system that is interconnected with the electric power system (EPS). This system has two main goals such as to serve the customer with reliable electric power and to improve power quality like harmonics and voltage event. This system is interfaced through the series and the shunt inverters because inverters are effective to control the output voltage and current. The shunt inverter can serve electric power to the customer and keep the harmonic current from flowing into the power system whereas the series inverter can compensate the voltage events such as voltage sag, swell, and interruption. Because DGs are interconnected with the electric power system, DGs should have countermeasures against disturbances from in the electric power system. This paper proposes the operating strategy of DGs including parallel operation mode, transition mode, and independent operation mode in consideration for the protection, islanding, and power quality. Using this operating strategy, the site load can be served high quality power.