换流阀用阳极饱和电抗器温升特性及优化

Temperature Rise Characteristics and Optimization of Anode Saturable Reactor for Converter Valve

阳极饱和电抗器(anode saturable reactor,ASR)是换流阀的关键一次设备,其在运行中因电磁损耗引发的温升问题明显并威胁绝缘体热老化。因此,准确分析ASR温升特性并寻求优化方法,对其状态评估、产品设计具有重要意义。为此首先根据发热机理和散热路径建立等效热路模型,定性分析了ASR实际运行中的温升特性;然后,建立ASR三维等效模型,结合瞬态传热原理来设定固体传热和空气对流参数,进一步应用基于湍流和实时混合假设的水冷却简化模型来模拟水冷散热过程,在兼顾准确性和高效性下开展多物理场耦合有限元仿真,定量计算ASR温度的大小变化和空间分布;最后,结合温度分布规律,提出不同截面积铁芯组合的结构优化方案,仿真验证了在电气性能不变前提下,各铁芯之间最大温差减少了原温差的91.7%,环氧树脂的最高温度降低3℃,为ASR的性能校验和参数设计提供借鉴。

Anode saturable reactor(ASR)is a key primary device for converter valves,and its temperature rise caused by electromagnetic losses during operation is significant and poses a threat to insulation thermal aging.Therefore,accurately analyzing the temperature rise characteristics of ASR and seeking optimization methods are of great significance for its state evaluation and product design.This paper first establishes an equivalent thermal path model based on the heating mechanism and heat dissipation path,and qualitatively analyzes the temperature rise characteristics of ASR in actual operation.Then,the three-dimensional equivalent model of ASR is established,and the parameters of solid heat transfer and air convection are set based on the principle of transient heat transfer.The simplified model of water cooling based on turbulence and real-time mixing hypothesis is further applied to simulate the process of water cooling and heat dissipation.The accuracy and efficiency are compromised,and the coupled finite element simulation of multi-physics simulation is carried out to quantitatively calculate the size change and spatial distribution of ASR temperature.Finally,combined with the temperature distribution law,the structural optimization scheme of the combination of iron cores with different cross sections is proposed.The simulation verifies that the maximum temperature difference between each core is reduced by 91.7%of the original temperature difference,and the maximum temperature of the epoxy resin is reduced by 3℃under the premise of the same electrical performance,which provides a reference for the performance verification and parameter design of ASR.