基于热通道模型的电能表外置断路器温升研究

Ｒesearch on Temperature Ｒise of External Circuit － breaker for Electricity Meter Based on Heat Channel Model

摘要:

为评估电能表外置断路器各部位热点的温升情况，研究了外置断路器处于稳态载荷时由内部热源向外的传 热过程; 然后基于热电比拟理论建立了断路器稳态热通道温升计算模型，给出了传热过程各环节的传导、对流和辐射 热流量以及热阻的计算公式; 最后通过建模仿真比较了不同负荷电流下所提方法与有限元模型对断路器内部导体热 点温升的计算结果，验证了所提模型的有效性。

Abstract:

In order to improve the accuracy of temperature rise monitoring for hot spot of external circuit － breaker for electricity meter，firstly，the heat transfer process of external circuit － breaker from the inside to the outside under steady － state load is analyzed． And then the steady － state thermal channel temperature calculation model for circuit breaker is established based on thermoelectricity analogy theory． The aspects of heat transfer conduction，convection and the radiation heat flux are given as well as thermal resistance formula． Finally，under different load current，the calculation results of the proposed method and the finite element model are compared through modeling and simulation for the the hot spot temperature rise of internal conductor of circuit breaker，which verifies the validity of the proposed model．