| 摘要 |
A multi-mode electronic wind turbine control system establishes a reference blade angle BR for a two-bladed, horizontal axis, variable pitch wind turbine rotor, the blade angle being regulated by a hydraulic pitch change mechanism (38). The rotor (10), via appropriate shafts and a gearbox (20), is coupled to a synchronous generator (24) to produce electrical energy which is fed to a power utility grid. The control system (36) provides closed loop pitch control for rotor acceleration rate during start-up, for rotor deceleration rate during shut-down, for speed control when the synchronous generator is off-line, and for power control when the synchronous generator is on-line. A single control integrator is used for all closed loop operating modes, with a rate limiter circuit in front of the control integrator to prevent integrator overtravel. The integrator has maximum and minimum blade angle stops, the minimum stop being variable as a function of rotor speed and wind speed. When on-line, power control is provided by a unique shaft torque control using proportional plus integral plus derivative controls in combination. |
