Comparison between locally produced low cost electric machine and wind generator

In Pakistan there is a short fall of electricity. Currently, the total amount of energy produced in Pakistan is about 19,500 MW through various resources such as hydel power, natural gas etc. The energy produces via hydel power is much less in comparison to production of energy through Furnace oil or Natural gas. Hydel power produces only 65,00 MW, while rest of 13,000 MW is produced either using Furnace oil or Natural Gas. Furthermore, nuclear and coal resources also contribute in energy production, but the yield is lower than the hydel power production, which is 450 MW and 150 MW respectively. The shortage of electricity reaches its peak i.e 6,000 MW in summer season and it is expected that this figure is expected to rise with time. Since Pakistan posses abundant wind resources for electricity generation, therefore it is essential to build indigenous low cost wind turbine to utilize these available resources efficiently and economically. This study specifically concerns with development of generator of horizontal axis of wind turbine. In this study, three-phase AC asynchronous induction motor has been converted into a wind turbine generator to produce a robust and economical design. For this purpose, a test rig, consisting of two induction motors, chain sprocket, motor coupling, capacitors, and load bank of 2.3 KWwere used. During experimental trials, high voltage oil based capacitors were used to magnetize the generator coil. As generator motor is rotated slightly above its rated rpm of 2800, capacitors starts magnetizing the coil, which in turns produce potential difference that reverses the motor behavior and it start working as a generator. During the laboratory trials, it has been shown that this approach presents a robust and economical solution for developing wind turbine generators, as these induction motors are easily available at considerably low prices in comparison to DC generators.