Measures, such as the floating of threshold, braking by positivesequence current, driving up the threshold during power swing, etc are suggested to prevent th.
采用浮动门槛、正序电流制动和静稳破坏后提高动作门槛值的方法，来防止系统振荡时误启动。
2
These disadvantages could be eliminated in three-phase systems if the energy account based on the integral of the active power of the positivesequence component with the fundamental harmonic.