Contents I. Introduction
Renewable energy is developing rapidly in China. It is the country with the largest and fastest growing renewable energy in the world. The capacity scale is the first ranks At present, the proportion of wind power grid-connected capacity in North China, Northeast China and Northwest China accounts for an increasing proportion of total installed capacity in the grid. There are 5 provinces (regions) with wind power grid-connected capacity accounting for more than 20% of total installed capacity. Wind power in Northeast China and North China have become the second largest installed power. With the continuous expansion of the scale of renewable energy grid connection, its influence on the power grid has gradually expanded from the local, which poses new challenges for the planning, development and stable operation of the power grid. Renewable energy generation has different static and transient characteristics than traditional synchronous power plants. The connection of renewable energy to the grid will have varying degrees of impact on the voltage stability of the local power grid. In a power grid with large renewable energy penetration, in addition to the voltage stability problem, renewable energy integration changes the original power flow distribution, line transmission power and inertia of the entire system, the power system transient stability has undergone tremendous changes. Renewable energy power generation technology and grid-connected scale are developing rapidly. The technical requirements for renewable energy and the research on grid-connected technology need to be continuously deepened and improved.
