I dont think its really as complicated as it seems. The Alternator is run via a gearbox to step up the speed. Because Power is a direct function of speed in a synchronised system, the only control required to regulate avtive power is speed control. This is simply achieved by altering the pitch of the turbine blades. Obviously there are a few warning areas that are protected against. 1. Overpower - where the alternator is run too fast and too much current flows from its windings. 2. Reverse Power - where the speed of the turbine is too slow and teh grid pumps into the alternator. Both of these conditions will cause the Circuit Breaker to open - protecting the turbine and alternator - but not before its reached the limits of its control region. Always remember that once an alternator is synchronised to the grid - its frequency and voltage match the grid. Changing voltage controls reactive power, and controller speed controls active power. Regards John ----- Original Message ----- From: "Debbie" To: "Microcontroller discussion list - Public." Sent: Monday, September 25, 2006 7:59 PM Subject: RE: [EE] Wind Power Question .. was Energy - Solar Power - IsraeliMojaveplan.. . --- peter green wrote: > > Australia. So how to they synchronise the turbines' output to the required > > frequency and phase? Just curious. > given the power big wind turbines put out i doubt they are feeding in at > only 415V but that doesn't really affect the issue at hand. > > from what i've seen there are two ways to do this, one is to make the wind > farm output DC and then invert it electroncially to feed the grid, the other > is to use a special generator design (iirc it has field coils energised from > a variable frequency inverter with the power drawn out through the rotor or > something like that, i don't remember the details). > > i belive small wind turbines that you can easilly purchase and install > yourself tend to be DC output. They're claiming 2MW per turbine so not exactly small scale. Not sure any inverter could handle power output at that level? --> http://www.wind-power.com.au/projects/wonthaggi/wonthaggi_01.asp The wind farm has a capacity of 12MW with each turbine able to produce 2 MW of renewable electricity. Sounds like synchronisation would be quite tricky? Debbie ____________________________________________________ On Yahoo!7 Messenger - IM with Windows LiveT Messenger friends. http://au.messenger.yahoo.com -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist