Power System Stability

Power system stability can be classified into static stability, transient stability, and dynamic stability.

(1) Static Stability of the power system refers to the ability to automatically restore to the initial running state without any non-periodic loss after the power system is subject to small interference.

(2) transient stability of the power system refers to the ability of each generator to maintain synchronous operation and transition to a new or restored State after the power system is greatly affected, usually the first or second step.

(3) the dynamic stability of the power system means that, after the system is disturbed, the system does not fail due to the constant increase of amplitude.

The transmission capacity of long-distance transmission lines is limited by the stability of these three types. It cannot be equal to or exceed the static stability limit, nor exceed the transient stability limit or dynamic stability limit. In China, due to the weak Grid Structure and outstanding transient stability problems, the transmission capacity of the line is smaller than that of other countries.