航天器蓄电池放电发热量测试方法系统误差分析

A systematic measurement error analysis of heat generation of battery by discharging for spacecraft

蓄电池发热量是航天器蓄电池热控设计的重要参数,其测试准确度直接影响热控设计状态和在轨工作温度。文章采用真空绝热量热法对蓄电池发热量测试系统进行了漏热分析,并给出了修正方法;以模拟蓄电池为研究对象,分析了蓄电池发热量测试误差,并提出了改善系统测量准确度的解决方案。结果表明,当放电时间大于1 h,航天器蓄电池发热功率在2~25 W范围内时,测试误差不超过6%,且发热功率越大误差越小;当发热功率大于10 W时,测试误差不超过3%,可以满足工程要求;对于发热功率较小(绝对值小于0.5 W)的小电流放电或充电,测试误差较大,但绝对值仍然较小,对实际工程影响不大。

For the heat generation of battery by discharging,the measurement accuracy could affect thethermal control design and the work temperature of the battery in orbit directly.In this paper,the vacuumadiabatic measuremeat method is used to analyze the heat leak of the test system,and a revision model isdeveloped.And the measurement errors of the heat generation from an analogue battery are studied,and thesolutions to improve the measurement accuracy are proposed.The experimental results show that themeasurement error is less than6%when the power of the heat generation is between2～25W and thedischarging time is longer than1h,and it decreases with the increase of the power.When the power is beyond10W,the error is less than3%,which meets the engineering requirements.It is meaningless to measure a mini-wattbattery,whose absolute value of power of heat generation is less than0.5W,since the measurement error will berelatively large yet.