Advanced DC Switching Power Supplies Of Mining System Research

With the development and application of electronic devices in the coal mine, the power in the coal mine has been developed from the initial linear power supply to the switching power supply, its quality directly affects the reliability of electronic devices. Therefore, using the new technology means to improve the efficiency of switching power supply is an eternal topic. The switching power supply is playing an important role in the coal industry. How to work of more efficient, to extend its life, to improve the reliability of power supply in this field have become the focus of attention. The work of switching power supply are adjusted in the on-off state, the main advantage is higher efficiency, up to 70% ~95%.After the development of switching power supply at home and abroad to understand the status quo and development trend, combined with the practical application of environmental requirements to ensure the safety of the power used in the mining to improve power efficiency and service life design of switching power supply must be considered as factors. Presents a constant current white LED driver for mining DC switching power supply to the mine under the DC power supply locomotives and miner's lamp. In this paper, the author describes the design principles of switching power supply , which is based on the constant current source, especially the car headlights were instead of white LED as a coal mine lighting applications. Then I introducd the whole structure of the switching power supply, followed the current control mode switching power supply works and its advantages. According to the specific demand for the whole structure of the circuit and application circuit design, using a typical current-mode PWM controller structure, the whole circuit is divided into six modules. On this basis, I finished the various sub-circuit design and analysis the important parameters related to the calculation.The innovation of this paper design digital switching supply instead of present linear supply. It is smaller size, the stability and working efficiency has been raised. Secondly, in the process of switching power supply design, I introduce the digital protection circuit. At the same time, the light source system is transformed. The experiments show that the power consumption is lower, luminous efficiency is improved.Since the switching power supply system is used in underground coal mines where is worse environment, so the analysis of electromagnetic compatibility problems is imporant for hardware circuit design. Due to hardware design to ensure the stability of the system work, so reliability can be further raised.Before hardware circuit were designed, I analysis its theoretical, I did some of the circuit simulation and circuit experiment, compulated the main parameters of the circuit. Experiments shown that in the same light intensity, the output power has been improved. As the white LED lights required constant current, while the switching power supply which is based on constant voltage can not provide a stable operating current, so it lights flashing and can not work properly. Constant-current-type inverter power overcome this shortcoming.