Implementation And Design Of Multiple Flameproof And Intrinsically Safe Power Supply

This dissertation analyzed the application technology and product situation of the existing intrinsically safe power supply (hereinafter referred to as intrinsically safe power supply), found that the existing intrinsically safe power supply has the following disadvantages:When the load is more, power-up is difficult, and a load capacity is poor. Output power of single intrinsically safe power supply is limited, and on the market the output of intrinsically safe power supply is more single or dual. For multiple outputs of intrinsically safe power supply, the output of all stripes is generally total output, it is difficult to meet the monitoring system isolation and signal transmission stability requirements. National mine triple-play security system was proposed and implemented, which requires a larger output power of intrinsically safe power supply, the existing intrinsically safe power can not meet this demand.For the above shortcomings, in order to enhance power-start capability and load capacity, this dissertation using frequency-hopping switching power supply technology, successfully developed a three isolated outputs flameproof and intrinsically safe power supply:5V/3A,12V/1A,15V/1A. The power supply adopts isolated flyback switching power supply topology and the power management IC with frequency hopping pattern, which improves power efficiency, but also extends the power life.3 outputs isolated from each other solve the problem of electromagnetic compatibility between systems, and improve the stability of the signal transmission between systems. The multiple flameproof and intrinsically safe power supply improves the coal mine automation, providing a solution for the triple play.Using longitudinal study of the safety theory and technology development history, horizontal contrast in the existing intrinsically safe power theory, technology and product situation, and combined with modern industrial design concept, this dissertation designed the first intrinsically safe power supply and secondary intrinsically safe power supply with a modular design concept. The DC-DC isolation module and dual over-voltage and over-current protection module are suitable for one or two times the intrinsically safe power supply. Each module can be interchanged after debugging. It not only simplifies the intrinsically safe power structures and components, but also reduces the cost of intrinsically safe power supply, and achieves easily industrial mass production. Through flow technology, a feasible solution is provided for intrinsically safe power supply of high power.The power supply using high-end and low-end dual over-voltage and over-current protection circuit, compared with the existing safe power supply using high-end dual over-voltage and over-current protection circuit, has more advanced design concept and more reasonable control logic. When a road in the short-circuit, overload or over-voltage, it can quickly turn off the intrinsically safe outputs by the practical test, at the same time there is no spark or small spark is produced, and the other way intrinsically safe output is normal. After the fault is cleared, the power supply automatically restore intrinsically safe outputs after the soft-start. The test results prove that the design is feasible and effective.