单相PWM整流器死区补偿方法

Dead time compensation method of single-phase PWM rectifier

为解决单相整流器死区效应导致相电压和相电流畸变、零电流钳位效应等问题,分析死区和零电流钳位效应,提出一种基于网侧电压谐振控制器锁相环的观测值进行判断,对单相PWM整流器死区时间进行补偿的新方法。该方法避免了电流检测中的噪声,使得过零点检测更加精确,不会引起相位延迟,并与根据电流值进行直接补偿的方法进行对比分析。所提出的方案能够有效地改善电流波形的正弦程度,且消除了传统方案需要检测电流方向的弊端,同时算法实现简单,具有工程实用价值。仿真和实验结果表明基于网侧电压观测值进行死区补偿方法使网侧输入电流总谐波畸变率更小、补偿效果更明显。

The dead-time effects of single-phase rectifier causes voltage and current distortions, zero-cur- rent clamping effects ,etc. To solve the problems, the dead-time and zero-current clamping effects were analyzed, and a novel dead time compensation method of single-phase PWM rectifier was proposed by the observation of grid input voltage based on resonant controller phase-looked loop. The new method avoids the noise of the current detection, so that zero-crossing detection is more accurate, and does not cause the phase delay. Comparative analysis was conducted with traditional dead time compensation method based on the current. The proposed scheme can effectively improve the degree of sinusoidal current waveform, and e- liminate the need to detect the direction of the current conventional solutions drawbacks. This algorithm is simple and has a practical value. The simulation and experiment results show that the grid input current to- tal harmonic distortion with grid input voltage observation is lower and compensation effect is better.