Design and realization of power supply system for outdoor on-line monitoring device

In order to outdoor on-line monitor high-voltage (HV) insulator, a method of designing a power supply system was presented, mainly including the capacity selection for photovoltaic (PV) array and rechargeable battery pack, the maximum power point tracking (MPPT) control for PV array, the charge and discharge strategy for rechargeable battery pack and the anti-interference design under violence electromagnetism environment, etc. In the stand-alone PV system, for cost-saving and non-stop running, the capacity of battery pack should approximately match the rating power of PV array according to the power consumption of the system. Under different temperatures and light intensity, charge control strategy on the main controller makes the PV array output its maximum power, in this way the power system can store as much energy as possible. Besides, a special and separate Sub Battery Control Module is designed for the main controller system, which manages the battery pack according to the lithium battery characteristics curve. In order to ensure the battery work efficiently and extend its life as well, a macroscopic strategy is proposed and runs on the main controller with the cooperation of the Sub Battery Control Module. At the same time, corresponding anti-interference design is adopted for the system so as to adapt to the particular surroundings. Up to the present, the system's anti-interference capability has been certified by correlative Electro Magnetic Compatibility (EMC) Test, such as electrostatic discharge (ESD), electromagnetic screen and power frequency interference. Operational results show the high stability and high efficiency of this power system.