The Energy efficiency diagnosis research of regional power grid loss reduction

Power loss is an important operation indicator of power grid enterprises. Lower power loss rate is not only the guarantee to ensure that the power grid is safe and stable, but also the base to certificate that power grid is operating in more economical, reasonable conditions. According to the notice of “The target responsibility assessment program of power grid enterprises to implement demand side management (Trial)” by the National Development and Reform Commission and other departments and the energy saving files of Twelfth Five-Year Plan, the comprehensive line loss rate of regional power grid should be less than 6.3%. Energy efficiency diagnosis is the effective method in which the regional power grid is studied as a whole and targeted loss reduction conclusions are deduced by comprehensive analyzing various aspects of the grid. The core of it is the comprehensive understanding of energy management level and energy status of regional grid, check out aspects the investigation with the existing problems and weaknesses of energy, find out energy-saving point and excavate potential of loss reduction. The work of Energy efficiency diagnosis should include two parts: middle-high voltage section (35kV and higher level voltage grid part) and low voltage section (10kV and lower level voltage part). The professional software for reactive power optimization is used to process the middle-high voltage section. The power flow and power loss in different operation modes is analyzed first. Then power flow is adjusted by changing the distribution of power supply equipment in the distribution network and it attained to loss-reduction and energy saving. For low voltage section, 10kV line and 400V distribution area are mainly study objects in which the aspects of reactive power flow, transformer economic operations and losses, line losses, load distribution should be analyzed. In the end the weak point of the system, a reasonable economic analysis and solutions sho- ld be detailed. Through the energy efficiency diagnosis of a regional power grid, the conclusions obtained match the actual condition very well. It is proved to be a valid and effective method.