TABLE OF CONTENTS Managing the electricity supply across the grid is not simply a case of generating enough electricity to meet the needs of all the customers connected to it. Wherever customers tap into the power network it has to be able to supply power that has well-defined characteristics and that is supplied with minimal disturbances or interruptions. What is more, the quality of the grid supply has become still more important as customers at all scales from the domestic to heavy industry use electronic equipment that can be sensitive to disturbances in the supply that last a fraction of a second.
The voltage and frequency of the network are the characteristics most often relevant for domestic users. The UK system at the domestic level is maintained at a voltage of 230 V (originally 240 V, but the standard was changed to bring the UK into line with mainland Europe). The supply frequency is 50 Hz.
The US system, in contrast, is maintained at 110 V and 60 Hz. All appliances for use in the UK are designed to operate at 230 V and 50 Hz, while US-marketed appliances require a 110 V, 60 Hz supply. Special converters are required to use US appliances in the UK and vice versa. Similarly, power-generation equipment is manufactured in different versions so that it can be used in grids that operate at 50 Hz or 60 Hz.
Whatever the function of an electrical appliance at whatever scale, it is converting some part...
