Research On High Frequency And High Voltage Charging Power Supply Based On Lithium Battery

At present,the suitable for exploration in geological complex mountain areas of the electric spark sources are are very clumsy,and it are very difficult to obtain the power supply of the city for field exploration.Based on this background,a lithium battery-powered high-frequency and high-voltage charging power supply was developed to charge for electric spark sources.Compared with the traditional power supply,it is easy to carry and solve the problem of access to power supply.First of all,this thesis studies the operating characteristics of series resonant and series-parallel harmonic charge power supplies.Charging power supply works in series resonant mode,the pulse capacitor in constant current charging mode,the charging voltage has a good linearity.Charging power supply operating in series-parallel mode,the charging current is reduced and resonator resonant period becomes shorter in the middle and ending of charging,the charging voltage linearity is deteriorated,Although the series resonant mode of operation is more suitable as a pulse capacitor charging method,However,under certain circumstances,the distribution of high-frequency transformer capacitance will significantly affect the series resonant charging power supply,and make series resonant power from the serial mode of operation into a series parallel operation mode.The charging power works in series and parallel mode in this thesis,and the matching characteristics of series-parallel resonant inverter and lithium-ion battery are studied.By adjusting the shunt compensation capacitor to optimize the lithium-ion battery output current,to make the lithium-ion battery smallest and meet the portability requirement.Secondly,this thesis designs a lithium battery-powered high-frequency and high-voltage charging power suply with 200J/s charge rate and 0-5KV charge voltage.The parameters of core components such as inductance and transformer were designed in the main circuit.the SG3525 chip is used in the control circuit,and adopt additional external circuit to set up multiple protection circuits,such as full charge protection,voltage threshold protection and charging delay protection.In this dissertation,a load short circuit experiment,transformer distributed capacitance measurement experiment and pulse capacitor charging experiment were carried out.The main purpose of the load short-circuit experiment is to measure the temperature rise of the transformer and the inductor and IGBTs.The measurement experiment for distribution capacitance of Transformer is mainly to compare the transformer distribution capacitance under different transformation ratio,it results in the transformer capacitance distribution becomes larger because the number of turns of the transformer winding becomes larger.Pulse capacitor charging experiment is mainly to verify whether the indicators of the charging power supply meet the requirements.The experiments show that it can make lithium-ion battery and series parallel resonant inverter to achieve the ideal match by parallel compensation capacitor,in the mean time,optimizing the output characteristics of lithium-ion battery.It not only improves the power density of the power system,and greatly reduces the volume of lithium-ion battery,increases lithium-ion battery life in the case of the requirements.