Research On Leakage Detection Technology In Low-Pressure Feed System

Leakage protection, overcorrect protection and the protection of ground together referred to as the three major coal mine electrical protection. However, the grid leakage protection in China’s development history is not long, played a major role. According to statistics, the events of deaths and injuries due to electrics shock in the low-voltage power are few, that this leakage protection of credit. With the rapid development of modern science and technology, electricity consumption doubled, making the equipment gradually to large-scale, continuous and automated direction, so that the quality of control switch on the power supply system must high. To meet this requirement, increasing the rated voltage of electrical equipment, enhancing the capacity and breaking capacity, while its compact structure, small size, easy operation, process performance, low cost, has become the main direction of development in China’s feed switch.The article designed a device of leakage protection set which combined additional DC sources and selective leakage detection of zero sequence power direction type. The core control circuit of this device is the micro controller STC12C5410AD and sampling circuit and the signal conditioning circuit, constitute the total feed switch branch basing on the theory of additional DC sources. And the sub-branch switch is based on elective leakage detection of zero sequence power direction type.After testing the set and being fielded calibrated residual operating value, meet the expected effect of the beginning of the design.