電壓型逆變器分段死區(qū)補償調(diào)制策略

劉和平 路瑩超 王華斌 苗軼如

摘 要：針對電壓源型逆變器中死區(qū)效應(yīng)引起的電流諧波畸變問題，提出了一種分段混合式PWM死區(qū)抑制策略。一方面在電機定子電流的非過零區(qū)域根據(jù)電流方向僅動作一個橋臂，實現(xiàn)了死區(qū)消除，并針對由器件導(dǎo)通壓降與開關(guān)延時產(chǎn)生的電壓誤差進行了修正；另一方面在過零區(qū)域采用脈沖等效時間補償法抑制零電流鉗位效應(yīng)產(chǎn)生的非線性誤差。此外在整個區(qū)域補償開關(guān)管的開通關(guān)斷延時及器件的導(dǎo)通壓降造成的非線性誤差。為了最大限度增加死區(qū)消除時間的占比，設(shè)計了上述兩種調(diào)制策略之間的最優(yōu)切換方法。仿真和實驗結(jié)果表明，死區(qū)分段消除與補償混合調(diào)制策略能夠顯著減小定子電流的諧波畸變率，并有效抑制死區(qū)效應(yīng)對系統(tǒng)的影響，證明了該方法的有效性和實用性。

關(guān)鍵詞：死區(qū)消除；死區(qū)補償；電流過零區(qū)；諧波畸變率；電壓型逆變器

DOI：10.15938/j.emc.（編輯填寫）

中圖分類號：TP 273 文獻標志碼：A 文章編號：1007 -449X（2018）00-0000-00（編輯填寫）

Abstract： A subsection integrated deed-time effect suppression strategy is presented in this paper to suppress current harmonic distortion caused by deed-time effect in voltage source inverter. On one hand， deed-time is eliminated by controlling only one bridge leg according to stator current direction of motor in nonzero current zone， meanwhile the voltage error caused by conduction voltage drop and switch delay is corrected. On the other hand， nonlinear error caused by zero current clamping effect is decreased by equivalent time compensation method based on pulse in zero current zone. Furthermore， in order to maximally eliminate the deed-time， an optimal switch method of the proposed PWM strategies is designed. The simulation and experimental results show the reduction of total harmonic distortion（THD） of stator current and the suppression of the influence caused by deed-time on the system， which demonstrates the validity and practicability of the proposed method.

Keywords： dead-time elimination， dead-time compensation， zero current zone， total harmonic distortion， voltage source inverter