| 摘要 |
A control system 32 for controlling operation of a hydroelectric turbine 16 comprises a converter system 20 to convert AC from the generator 18 having a voltage and frequency that is proportional to a rotational speed of the turbine 16, to AC power having a voltage and frequency of a transmission system. The control system 32 controls the converter system 20 in response to water flow speed through the turbine 10 to control rotation of the turbine. Below rated speed, the rectifier 2 is operated as an uncontrolled rectifier, and the firing angle of the inverter thyristors 8 is controlled to provide an optimum value of dc link voltage to maximise power output from the turbine. Above rated speed, both inverter and rectifier thyristors are controlled to limit output power to a desired maximum value. Turbine speed is thus allowed to rise to limit torque by reducing turbine efficiency. An inductor 30 is provided to smooth the DC current. |
