Research And Realization On Power Supply And Distribution Module Of Key Technology Of A Measurement System

Power supply and distribution module is the energy source and basic guarantee of the measurement system. The reliability and stability of power supply and distribution module directly affect the accuracy of the test parameters measurement and the comprehensive performance of measurement system. This paper mainly based on the battery charged and discharged management and implementation of the accurate distribution, designs a wide working temperature range, high conversion efficiency power supply and distribution module which meets the requirements of technical indicators.In the module of lead-acid battery charged and discharged management, in order to maximize battery capacity and life, the charged way of multi-stage is selected for the battery. This way can intelligently sequence the transformation of different phases. Then, due to the weak discharged ability of lead-acid battery at low temperature, the circuit of power supply switch is designed to ensure that the battery can provide enough energy in-45℃. At the same time, voltage monitoring circuit prevents the battery from being overcharged and the deeply discharged state, and the key voltage is conducted to evaluate the stability of power supply. In the distribution module, the regulator circuit is designed to stabilize the battery output voltage and ground power supply voltage. The circuit of power transformed realizes the turning from ground supply to the bounced power supply and outputs enabled voltage which controls the process of distribution. Then, each function module, according to the requirement, realizes power conversion for the stability of the output voltage of power management module. The designs of the constant voltage source circuit, constant current source circuit and the isolated power supply circuit are analyzed in details. In order to improve the reliability of power supply module, this paper analysis the factors that affect the performance of the battery charged and discharged through the theoretical and experimental, and introduces measures taken in the design that the power heat dissipation and anti-interference has carried.In the end, using the testing platform, the performance of the power supply and distribution module is tested, including the charged test, discharged test, the feasibility experiment of supply switch circuit at low temperature of the battery, and the function verification test in the normal work of power supply and distribution module. The test results show that the module of power supply and distribution based on lead-acid battery as the center is safe and reliable, and can work 5 hours in-45℃~ 60℃and fits perfectly the requirements of the design. The measurement system has been successfully applied in the flying test.