田湾核电站线功率密度保护参数计算

Calculation of Protection Parameter of Linear Power Density in Tianwan Nuclear Power Station

田湾核电站(TNPS)堆内核测量系统的54个中子温度测量通道分成4组,每组通道将自给能探测器电流转换为功率并通过扩展计算获得全堆芯的功率分布。电流转换为功率的系数等参数由堆内测量系统上层服务器计算获得并传递给下层服务器。每个燃料组件最大线功率密度由周边影响区域内的4个中子温度测量通道计算的线功率密度值加权平均得到,权重系数与自给能探测器到周边影响区域内燃料组件的距离有关。本文阐述这种由自给能探测器电流计算线功率密度保护参数的方法。该方法简易、响应及时,且误差小于5.7%,已成功应用在田湾核电站运行机组的实时在线保护中。

Fifty-four neutron-temperature measuring channels(NTMCs) of in-core instrument system(ICIS) in Tianwan nuclear power station(TNPS) are divided into 4 groups, and the self-power nuclear detectors(SPNDs) current in channels of each group can be converted to power. The in-core power field can be obtained by extended calculation. Parameters such as the coefficient of converting current into power are calculated by ICIS server computer of upper level and transferred to ICIS server computer of lower level. The maximum linear power density of each fuel assembly(FA) is weighted average of linear power densities calculated by four NTMCs in surrounding impact area. The weight coefficient is relative to the distance from SPND to FA in surrounding impact area. This paper expounds the calculation method on protection parameter of linear power density by SPND's current. This method is simple and timely response, and the error is less than 5.7%. It has been successfully used in the real-time online protection of TNPS operation units.