Research And Design Of Solar Energy Electric Fence Control System

The electric fence obstructs the intruders by the method of high-voltage pulse discharges. The high-voltage pulse doesn't discharge persistently, so it won't cause any harm to the intruders. Currently available electric fence use to prevent human's intrusion, it use commercial power supply which can't use in farmland where no power source, and there is some problem with boost circuit and discharge mode. In this dissertation, the existing products'problems are analyzed in detail, and electric fence control system used in farmland to prevent animals was designed.There are two disadvantages with currently available electric fence; Firstly, in boost circuit, after big capacitor charging, discharge through iron-core transformer, so it brings strong current impact to the MOSFET and capacitor, as a result, it's working life will be shortened. Secondly, electric fence work on equal interval discharging mode whether there is intruders, so a lot of energy was wasted and the efficiency is reduced. In order to overcome first disadvantage, backward boost converter was designed to obtain high-voltage pulse, so it can extend the service life of device. This circuit saves iron-core transformer and big capacitor, so the size of the circuit is reduced. In order to overcome second disadvantage, constant voltage pulse mode was designed, in this mode, host detect working state of the fence and adjust discharging mode, so the efficiency of standby state was increased remarkably.The system uses solar energy as power supply, so it isn't restricted by the condition of commercial power supply. Linking of the host and extensions is based on DC bus mode, both energy and communication signal transfer through DC bus. When protect area size is changed it is just need to adjust the number of extension, and set extension's ID, software upgrade is not necessary, so operation and maintenance is convenient.In this dissertation, the size of the boost circuit is decreased 50% of currently available electric fence. The calculations show that the efficiency of the extension works at constant voltage pulse mode is improved over 10 times than the extension works at fixed interval mode at waiting time.