Research On The Delamination And Subarea In Urumqi Power Grid Planning

In recent years, the rapid development of power grid in Urumqi, the structure power grid has formed 750kV backbone ring network and 220kV ring network to complete the power transmission. However, with the rapid development of the scope of power grid, the voltage of power grid is getting higher and higher, the scale of the power is becoming bigger and bigger, so that the operation mode of power is becoming more and more complex. A large number of ring network operation mode, especially the operation mode of the high and low voltage electromagnetic loop network has brought lots of unfavorable factors to the power grid. Firstly, the some negative effects such as the short circuit capacity beyond the capacity of switching equipment, the load flow is hard to control, the setting production becomes more complex and so on, in the other hand; what is more, when the weak part of the loop line with high voltage fault and exit, the a large number of power flows from the high voltage power grid to the low voltage power grid, so that the transformer or line overload, protection malfunction and even destroy the system stability.Focus on the rapid growing demand for the electric load, how to reasonably use the existing resources to obtain the maximum power supply capacity and ensure the safe and stable operation of the power grid is the crux. Make a reasonable hierarchical partition planning for the Urumqi power grid, it will strong guarantee the load demand and the Power external demand, what is more, it can also effectively prevent the short circuit capacity which is caused by high and low voltage electromagnetic loop network over proof and prevent problem that the load flow is hard to control.This paper according to the development planning of Xinjiang 750kV power, takes Urumqi 750 kV/220 kV power grid as the research object, combines with the actual situation of Urumqi power grid analysis the existing problems in Urumqi power grid, predicts the demand of electricity, proposes the hierarchical partition plan of Urumqi power grid and depth analysis the loop-opening project for the power grid. Based on the operation mode of Urumqi in the summer of 2020, builds and analysis the evaluation indexes of power flow distribution and short circuit current.This paper recommends the best program through the study of different electromagnetic loop-opening projects and combines with the verification for electrical calculation. The calculation result shows that the recommended scheme is in line with the actual situation of Urumqi power grid; the sort-circuit current can be controlled in a reasonable range, so the recommended scheme satisfies the operation requirements of power grid.