A New Approach for Reactive Power Economic Dispatch by Jacobian Based Distribution Factor

• Main Author: 陳天益
• Other Authors: 陳宣泰
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/05120848793000802663

碩士 === 建國科技大學 === 電機工程系暨研究所 === 97 === Reactive power optimal dispatch is more difficult than real power dispatch. In general, reactive powers are always supplied by the local distribution centers and can seriously affect the bus voltages. But in complex interconnected power systems, the sudden and unusual requirements of reactive power are still supplied by the generators. As a result, the reactive power flows on transmission lines can not be ignored and will cause some losses in transmission. Based on this reason, most system researchers treat the reactive power dispatch as an optimal problem by taking the transmission losses as objective function. In this thesis, the transmission losses are expressed in terms of line flows which are formulated by Jacobian based distribution factor (JBDF). The conventional JBDF sensitivity factors can only reflect the changes of reactive loads, but not reactive generating powers, to the line flows. They should be revised by taking some adjustments and involved in the loss models. Based on these models, three solution methods for the reactive power economic dispatch problem have been proposed and tested by IEEE 14-Bus and IEEE 30-Bus sample systems. As demonstrated by the simulation results, the proposed revised JBDF sensitivity factors can precisely compute line flows during dispatch computations. They make the computations of transmission losses and line flows to be very easy without the need of executing power flow program. This good feature also makes the reactive power dispatch problem become easy to approach and results in excellent results. The proposed methods are very suitable for real time applications due to their fast computations.