Applying Of UPFC In Modern Distribution Network

ABSTRACT

The fault in the distribution network will cause voltage sags, three-phase imbalance and frequency fluctuations, seriously, forced to exit the system, increasing the instability of power and voltage in the distribution system. To solve many problems caused by the access of large-scale distributed wind power, to improve the penetration of wind power  , to promote the development of wind power, to ease the environmental and economic issues that aroused by traditionally centralized power generation, and to increase the quality and reliability of power supply. UPFC (Unified power flow controller, UPFC) is the most powerful FACTS controllers, it is well known to change the system parameters quickly and regulate the system voltage magnitude and phase angle so that it can control the system voltage and power flow. Taking the unified power flow controller as an example, this paper states the applying foreground of flexibility AC transmission system technology in distribution system. It proposes the idea that integrating the energy storage system into the DC bus of the unified power flow controller, The voltage regulation feature of UPFC to compensate for voltage asymmetry and fluctuations of distribution system voltage; the use of power flow regulation of UPFC can ensure DG working normally, even if the system is in failure to enhance the power system transmission capacity, when there exists the active shortage in the system, it need to provide active support to the static regulation of the system voltage and power flow for UPFC.

EXCITED SYSTEM

— The fault in the distribution network will cause voltage sags, three-phase imbalance and frequency fluctuations seriously, will be forced to exit the system

increasing the instability of power and voltage in the distribution system

PROPOSED SYSTEM

— The voltage regulation feature of UPFC to compensate for voltage asymmetry and fluctuations of distribution system voltage; the use of power flow regulation of UPFC can ensure DG working normally, even if the system is in failure. 

— UPFC (Unified power flow controller, UPFC) is the most powerful FACTS controllers, it is well known to change the system parameters quickly and regulate the system voltage magnitude and phase angle so that it can control the system voltage and power flow.

ADVANTAGES:

This paper takes UPFC as an example; explain the effect of FACTS technology on the improvement of power quality in the modern distribution network with renewable energy represented by wind power. 

In this paper, the proposed topology model in which the ESS compatible with wind power will be access to the traditional UPFC DC bus is expected to be able to damp the oscillation of wind power and improve the capacity wind power through, under the premise of guaranteeing the power quality of distribution network.