Design And Key Technology Research Of Power Supply And Distribution Unit Based On Lithium Battery

Power supply and distribution unit directly connects to the terminal equipment at the endof the telemetry system. It is an important hub for terminal equipment to provide power anddistribute electric energy. The stability and reliability of the power supply and distribution unitdirectly reflects the degree of the load on its power supply capacity and quality of powersupply. It is a comprehensive reflection of the telemetry system reliability indicators.With the rapid development of the cause of China’s national defense, the spacecraft’smission is more complex. With an increasing number of terminal equipment and the growingelectricity power, the telemetry system would put increasingly high requirements, such asmore reliable power supply and more stable transmission for the power supply anddistribution unit. The topic for the large power consumption of the equipments in the currentmonitoring and control system, as well as the limitations of the test conditions, developed twokinds of power supply and distribution design. By comparative analysis of the viability andstability of the two programs, the final selection is a kind of power supply and distributionunit with the ground switch.This article in the supply and distribution unit was based on lithium batteries as theelectrical storage and power supply modules. The unit used electromagnetic relays to controlthe charge and discharge of the lithium batteries. The design was mainly composed bymonitored by power supply of the ground monitoring station, control device of the groundturning electric, distribution equipment and the terminal device. The power supply of theground monitoring station provided supply voltage to control device of the ground turningelectric, at the same time, also provided charging voltage to lithium battery in the distributionequipment. The control device of the ground turning electric had some built-in electromagnetic relay. It was used to control the output of the pulse signal from0to28V,which is controlled by on-off the electromagnetic relay. When the control device of theground turning electric send a power supply command, which is a pulse signal form0of28V,two groups of four electromagnetic relays in the power distribution unit worked together tocontrol the lithium battery to discharge. When it send a power-off control command, which isa pulse signal form0of28V, the electromagnetic relays in the power distribution unit workedtogether to control the lithium battery to stop discharging. Therefore, the lithium battery in thepower distribution unit discharging or not, directly determined the terminal device workingproperly or not. In view of the equipment’s reliability, stability and other factors to consider,this article focused on the long-term charging problem between the power supply of theground monitoring station and the lithium battery in the power distribution unit, thedifficulties of design between the control device of the ground turning electric and distributionequipment in terms of controlling for power-off, and the reliability problems of the powersupply between the lithium battery and the terminal device for in-depth analysis. The paperalso performed these related circuit design above the importance and difficulties.Developed for the power distribution unit had been applied to an aircraft flight test. Thetest results show that, the unit has more stable performance and higher reliability, which wascompared to previous power supply and distribution system. It has also achieved all designrequirements of the mission. Finally, the article summarized some problems encountered inthe process of system implementation, and described the direction of the future development.