The first problem that arises from this power plant is the determination of the generator to be used, generator simultaneously (synchronous generator) or no-simultaneous generator (asynchronous generator), both for the rotor cage and the rotor turns. The generator with permanent magnet is also being developed as a solution to power generation turbines at low rotation without having to use the gear box.
The use of synchronous generator at the same time we make it easy to adjust the output voltage and frequency generator by regulating the field current of the generator. Unfortunately, the use of synchronous generator at the same time rarely applied due to the expensive cost, requires current amplifier and requires complex control systems.
Asynchronous generator is often used for wind turbine systems and micro hydro systems, both for fixed-speed systems and variable speed systems.
The advantage of fixed-speed system using asynchronous generators are cheap, simple and robust system. This system operates at a constant speed, so that the turbine only obtain at maximum power . This system is suitable for application in micro hydro that water flow rate can be regulated mechanically. The weakness of this system is the generator requires reactive power to generate electricity so that the capacitor banks should be installed. The system is vulnerable to the pulsating power and are prone to mechanical changes.
