基于无源性控制的变压器低频加热电源  

Low-frequency transformer heating source based on passivity control

作　　者：朱小帆[1] 查晓明[1] 秦亮[1] 黄坡[1] 

机构地区：[1]武汉大学电气工程学院,湖北武汉430072

出　　处：《电力自动化设备》2015年第6期166-171,共6页Electric Power Automation Equipment

基　　金：国家自然科学基金资助项目(51207115)~~

摘　　要：针对目前大型变压器加热干燥方法存在的受热不均、绝缘受损等缺点,设计了一种应用于大型变压器干燥的低频加热电源装置,能够在电压等级较低的情况下,为待干燥的负载变压器提供较高的低频加热电流。该低频加热电源采用交-直-交变换原理,整流侧为2个不控整流桥,逆变侧采用中性点箝位三电平结构;计算偏差中线电流以达到直流电容电压均衡控制,采用无源性控制理论,构建无源性控制模型,确定无源性控制比率,确保了对指令低频电流的渐近跟踪;通过给定的较大指令低频电流,保证负载变压器的加热效果。仿真结果表明,所提控制算法能够在输出低频电流的同时实现直流电压的均衡控制,且稳态特性好、响应速度快、算法实现简单、鲁棒性强。380 V、700 k V·A的工程实际应用表明低频加热电源具有良好的加热效果。A LFHS（Low-Frequency Heating Source） is designed,which provides biggish heating current at lower voltage level to uniformly dry the large load transformer without insulation damage. With two uncontrolled rectifiers at rectifier side and a three-level NPC（Neutral Point Clamped） converter at inverter side,it adopts the AC-DC-AC transformation principle,applies the calculated middle-line current to balance DC capacitor voltage, builds a passivity control model based on passivity control theory and determines the passivity control rate to asymptotically follow the low-frequency current reference,and ensures the heating effect of load transformer by a bigger given low-frequency current reference. Simulative results show that,the proposed control algorithm ensures the output of low-frequency current and the balance of DC voltage at the same time and the designed LFHS has nice static performance,rapid response,simple algorithm and strong robustness. The practical engineering application of a 380V,750kV.A LFHS verifies its excellent heating effect.

关 键 词：变压器 干燥 低频加热电源 中性点箝位 SPWM 无源性控制 

分 类 号：TM46[电气工程—电器]