电子式电流互感器高压侧取能装置的设计

有源型电子电流互感器高压侧工作电源的取能方式是影响互感器可靠性和精度的关键环节。文章针对有源型数模转换式电子电流互感器，给出其高压侧取能装置的设计方案，利用电磁线圈从母线上摄取能量，接收的一次侧传变电流经整流、滤波、稳压等处理后向互感器高压侧供电。该设计方案选用非晶材料制作取能线圈铁心，采取双铁心并行工作方式，并通过稳压管泄放二次侧电流，保证取能装置能够在适应母线一次电流较大变化范围的基础上长时间稳定工作，同时采用固态继电器解决了大功率稳压管工作中产生大量热能的问题。该方案实现简单，造价低廉，经试验证明是可行的。

Design of a High Side Energy Extracting Device for Active Electronic Current Transformer

How to obtain working power supply from high voltage side of active electronic current transformer (ECT) is the key link impacting the reliability and accuracy of the instrument transformer. Aiming at active ECT with A/D converter, a design scheme to gain working power supply from the high voltage side for the ECT is given. The high voltage bus current is transformed by electromagnetic coil, then it is transmitted to rectifying, filtering and voltage stabilizing circuits in turn, and then it is used as the power supply for the high voltage side of active ECT. In this design scheme the core of electromagnetic coil is made of nanocrystalline material, and the double-core concurrent working mode is adopted. The secondary current is bled off by stabilivolt to ensure the proposed device can adapt to the wide variation range of primary bus current and stably operate in long-term. To solve the problem of temperature rise accompanying with the running of high-power stabilivolt, the solid-state relay is adopted. The proposed design scheme is low cost and easy to implement. Test results show that it is feasible.