| 摘要 |
PURPOSE:To maximize the contribution of the generator to the voltage recovery characteristic in the system by removing the overexcitation controller within a certain time out of the system. CONSTITUTION:The setting circuit 15 outputs the allowable field current signal according to the deviation between the set signal of the temperature setting device 14 and the internal cooling water temperature of the generator 1. The deviation detector 8 outputs the deviation signal between the allowable field current signal and the field current value. The comparator 16 outputs the detection signal as the field current exceeds the allowable field current. With continuation of the detection signal beyond a specified time, the timer 17 is actuated to excite the relay 18, which causes the contact 18a to close whereby the overexcitation control signal is fed to AVR4. Said action enables the field current to be fully used to the allowable capacity limit while contributing to the improved stability of the voltage control in the system as to the period permissible to the generator with a short overexcitation. |
