交直流混合微电网TNPC变换器的死区电压矢量偏差及修正

对T型中点箝位型双向变换器在矢量空间中的死区电压矢量偏差进行分析，总结其发生规律，并根据参考电压矢量的位置和幅值得到提前修正的指令电压矢量。从线性调制空间到过调制空间得到相应的伏秒特性方程的调整办法。同时，考虑到系统在动态扰动下可能引发的欠补偿或过补偿，引入一个补偿深度的调节因子，实现脉宽调制(PWM)指令电压矢量的自适应修正。该方法可推广到有更多电平的变换器中，避免了采用传统PWM脉冲宽度整形法时出现的脉冲损失或饱和问题。

Dead-time voltage vector deviation and correction of TNPC converter in AC-DC hybrid microgrid

The dead-time voltage vector deviation in the vector space for TNPC(T-type Neutral-Point-Clamped) converter is analyzed, and its occurrence rules are summarized. The pre-corrected instruction voltage vector is obtained according to the position and amplitude of the reference voltage vector. From the linear modulation space to the over-modulation space, the corresponding adjustment approach of the voltage-second characteristic equation is obtained. In addition, considering the fact that dynamic disturbance of parameters might result in over-compensation or under-compensation, the correction factor is introduced to provide an adaptive correction of PWM(Pulse Width Modulation) instruction voltage vector, which can also be used in multi-level converters. The proposed approach avoids the issue of pulse loss or saturation that suffered by traditional PWM pulse width shaping approaches.