基于高频高压电除尘用LCC谐振电源特性的网侧整流方式比较  

Grid-side rectification mode comparison based on characteristics of HF-HV LCC resonant power-supply for electrostatic precipitator

作　　者：刘和平[1] 罗异[1] 刘庆[1] 邓力[1] 周奇 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030 [2]重庆赛力盟电机有限责任公司,重庆401329

出　　处：《电力自动化设备》2017年第5期21-27,共7页Electric Power Automation Equipment

基　　金：输配电装备及系统安全与新技术国家重点实验室自主研究项目(2007DA10512713302)~~

摘　　要：高频电除尘电源系统由网侧整流器和高压电源组成。高压电源采用LCC谐振变换器,其工作于双脉冲模式时更利于控制,基于该模式下电路模型,详细推导了各时间段解析表达式,确定了输出限制条件。通过建立功率平衡方程并定义电压传输系数、等效负载系数及频率系数建立三者间数学关系并绘出相应关系曲线作为后级参数设计依据。深入分析后级工作特性并证明在临界频率下调节母线电压的调压特性比断续模式下调频调压的更好,高压侧输出电压在最大值以下调节时谐振电流峰值大幅减小。为对比不同整流设备与后级特性匹配的差异并解决目前高频电除尘电源系统因普遍采用三相二极管整流器作为前级而给电网带来的谐波注入问题,分别设计了近正弦输入电流整流器及PWM整流器作为入网设备,用Saber仿真软件对2个具有相同额定输出功率、电压的整机系统特性进行对比分析,结果验证了特性分析的正确性并证明PWM整流器因其直流母线电压可控且可调从而能更佳地匹配电除尘电源系统后级工作特性。The power-supply system of electrostatic precipitator consists of the grid-side rectifier and the high- voltage power-supply. LCC resonant converter is widely adopted in the high-voltage power-supply and its control becomes easier when it is working in the double-impulse mode. Its analytical expression is deduced in detail based on its circuit model in this mode for each time section and the constraint condition is determined. A power balance equation is established,its voltage distribution factor,equivalent load factor and frequency factor are defined,the mathematical relationship among three factors is built,and corresponding relationship curves are drawn for the parameter design of its rear-stage. The working characteristics of its rear-stage are analyzed and it is proved that,the performance of voltage regulation by the bus-voltage ad- justment in critical frequency mode is better,i.e, the peak resonant current is smaller when the HV-side output voltage is below the maximum,than that by the frequency adjustment in discontinuous mode. Since three-phase diode rectifier,which is widely adopted in the front-stage of existing electrostatic precipitator power- supply system,may inject harmonics into grid,nearly-sinusoidal input-current rectifier and PWM rectifier are designed as the grid-connection device and their matching performances with the characteristics of its rear- stage are compared. Saber software is applied to compare the overall performances of two actual systems with same rated output power and voltage,and the result proves that,the proposed method of characteristic analysis is right and the designed PWM rectifier can well match the rear-stage working characteristics due to its controllable and adjustable DC-voltage.

关 键 词：LCC谐振电源 双脉冲模式 调压特性 谐振电流峰值 整流器 

分 类 号：TM46[电气工程—电器]