Distribution networks generally use closed loop design, open-loop operation, its structure radially

In the urban grid system, the primary network is 110KV and above voltage level of the grid, the main connection mcb circuit breaker the high pressure (220KV and above) the role of the grid
Distribution refers to the voltage level of 35KV and below the grid, the role is to give the city all kinds of electricity load distribution stations and power supply
Distribution networks generally use closed loop design, open-loop operation, its structure radially. mcb circuit breaker line diameter Electric energy meter the power lines, resulting in the distribution network R / X bigger. Because distribution line R / X is large, so that the transmission grid in these algorithms commonly used in the distribution network power flow calculation is difficult to guarantee the convergence.