Almost all wind energy systems require a controller to prevent damage to the turbine and the load. With advances in power electronics and microcontrollers, inexpensive yet sophisticated power controllers can be produced which are also capable of enhancing the power extraction of the overall system. These controllers may use DC-DC converters to boost the voltage of a given power source up to a higher voltage to match the requirement of a load, such as in the case of the solar panel or wind turbine operating below the charging voltage of a battery pack. A DC-DC converter, either buck or boost, may also be used in impedance matching a power source to a given load with an improvement in the overall system efficiency. With modern microcontrollers and high-frequency power switching devices a peak-power tracking controller can be developed which includes many functions such as load over charging protection, load prioritization, and turbine breaking. Such a peak-power tracking controller can greatly enhance the overall power production of a wind turbine system, and may cost a small fraction of the price of the turbine. With reasonable care the wind power system can be modelled and the cost/benefit ratio of a controller can be determined. In many applications the additional cost of a sophisticated controller is justified by the increased power yield of the system.