Research On Operation Control Method Of Connecting Small Hydropower Station To The Grid In Enshi

The abundant and widespread small hydro power is a kind of renewable energy sourcewhich is clean and green, it is better in mature technology, commercialization and economycompared with other renewable energy sources because of its competitive advantages ininstalled cost and electric price. The reliability of power supply is increased in the area ofthe small hydro power, because it is able to flatten the voltage sag effectively, eliminate theoverload and transmission congestion, reduce the power peak load and increase thetransmission margin, however, the small hydro power will affect the quality of electricenergy, transmission loss, relay protection, reactive power, voltage and so on.The power flow, voltage and system security after the integrating of the small hydropower are analyzed based on the power grid of Enshi, fundamental and theoretical researchof voltage regulating measures under the operation mode of low load in wet seasons isproposed, the model of Enshi power grid in Power System Analysis Software Package(PSASP) is established, and the phenomenon of overvoltage and high load factor of somelines because of the transmission of the small hydro power under operation mode of lowload in wet seasons is pointed out in this paper. The area of Xianfeng is selected as theresearch object because of the outstanding voltage problem in Enshi power grid based onthe power flow analysis, several voltage regulating strategies are proposed, and the best oneamong them is obtained by the comparison of simulation analysis, the static and transientstability of Enshi power grid is analyzed through the check of N-1single contingency andN-2severe contingencies of some typical lines based on the model of PSASP.