What Is a Homopolar Generator?

A motor that converts mechanical energy into electrical energy. It is usually driven by a steam turbine, a water turbine or an internal combustion engine. Small generators can also be driven by windmills or other machinery via gears or belts. There are two types of generators: DC generators and alternators. The latter can be divided into two types of synchronous generators and asynchronous generators. The most commonly used in modern power stations are synchronous generators. The characteristic of this generator is that it is excited by DC current, which can provide both active power and reactive power, which can meet the needs of various loads. As asynchronous generators do not have independent field windings, their structure is simple and easy to operate, but they cannot provide reactive power to the load, and they also need to draw hysteresis magnetizing current from the connected power grid. Therefore, asynchronous generators must be connected in parallel with other synchronous motors, or a considerable number of capacitors must be connected in parallel. This limits the application range of asynchronous generators, which can only be applied to small automated hydropower stations. DC generators used in urban trams, electrolysis, electrochemistry and other industries used DC generators before the 1950s. However, the DC generator has a commutator, the structure is complicated, the manufacturing is time-consuming, the price is more expensive, and it is prone to failure, difficult to maintain, and less efficient than the AC generator. Therefore, since the advent of high-power controllable rectifiers, there has been a tendency to use AC power to obtain DC power through semiconductor rectification to replace DC generators.