Renewable Systems

Solar transformers have separated primary and secondary windings with an earthed screen between them. Not only does this isolate the solar installation from the supply network but it also eliminates grid related disturbances from reaching the solar generator. In conjunction with an AC inverter, the transformer efficiently converts the trickles of energy received from the sun (direct current) to a voltage that can be fed onto the public supply network.

Often motor-driven dynamic systems with either large, rotating masses or used for moving heavy weight loads, build up high levels of kinetic or potential energy so that when they are required to decelerate or stop then this presents a problem. The motor is required to run in reverse and operates as a generator of electri-cal energy which has to be diverted or dissipated. One simple method of doing this is to feed the surplus electrical energy into braking resistors which...

Wind turbines are designed to produce electrical energy as cheaply as possible with maximum yield with wind speeds of around 15 metres per second (30 knots or 33 miles per hour). They have an expected oper-ating life of 20 years, which is more than 120,000 hours. In addition to achieving maximum power yield some of the important issues with wind turbines are the speed of rotation, quality of the power that is produced, protection of components, size and cost of...