中压(medium voltage,MV)配电网中无功补偿电容器易与网侧电感形成并联谐振,放大公共耦合点(point of common coupling,PCC)电压。为了应对两电平并联型有源电力滤波器(shunt active power filter,SAPF)不适用于中压配电网场合,且只抑...中压(medium voltage,MV)配电网中无功补偿电容器易与网侧电感形成并联谐振,放大公共耦合点(point of common coupling,PCC)电压。为了应对两电平并联型有源电力滤波器(shunt active power filter,SAPF)不适用于中压配电网场合,且只抑制谐波不能解决谐波与谐振同时存在的问题,提出了一种基于模块化多电平的并联型有源电力滤波器(modular multilevel converter based SAPF,MMC-SAPF)的谐振阻尼技术。首先分析了MMC-SAPF的工作原理,采用载波移相调制策略(phase shifted carrier PWM,PSC-PWM)以及电容电压平衡控制策略,以实现MMC-SAPF的高等效开关频率。然后分析了MV配电网的谐振机理,指出谐波抑制策略失效的原因,在此基础上,提出将MMC-SAPF控制为谐振频率处的虚拟电阻,提高系统阻尼比以治理谐振。搭建了一台60 V/2 kVA的实验样机,并构建7次谐振环境,实验结果验证了复合控制策略阻尼谐振的有效性。展开更多
Absrtact: The principle of ZVS - PWM inverting circuit is first described by means of inverting welder supply. The contrastive study is made on switching characte -ristics and switching losses of IGBT between ZVS - PW...Absrtact: The principle of ZVS - PWM inverting circuit is first described by means of inverting welder supply. The contrastive study is made on switching characte -ristics and switching losses of IGBT between ZVS - PWM and hard - switching.展开更多
a Pole voltage waveforms (VA20 and VA40) for modulation index 0.4 (middle trace is A-phase voltage waveform) x-axis: 1 div.=10ms, y-axis: 1 div.= 100V b Normalized harmonic spectrum for pole voltage of Fig. 9a c A-pha...a Pole voltage waveforms (VA20 and VA40) for modulation index 0.4 (middle trace is A-phase voltage waveform) x-axis: 1 div.=10ms, y-axis: 1 div.= 100V b Normalized harmonic spectrum for pole voltage of Fig. 9a c A-phase current and phase voltage for modulation index 0.4 (reference space vector is in inner layer)展开更多
文摘中压(medium voltage,MV)配电网中无功补偿电容器易与网侧电感形成并联谐振,放大公共耦合点(point of common coupling,PCC)电压。为了应对两电平并联型有源电力滤波器(shunt active power filter,SAPF)不适用于中压配电网场合,且只抑制谐波不能解决谐波与谐振同时存在的问题,提出了一种基于模块化多电平的并联型有源电力滤波器(modular multilevel converter based SAPF,MMC-SAPF)的谐振阻尼技术。首先分析了MMC-SAPF的工作原理,采用载波移相调制策略(phase shifted carrier PWM,PSC-PWM)以及电容电压平衡控制策略,以实现MMC-SAPF的高等效开关频率。然后分析了MV配电网的谐振机理,指出谐波抑制策略失效的原因,在此基础上,提出将MMC-SAPF控制为谐振频率处的虚拟电阻,提高系统阻尼比以治理谐振。搭建了一台60 V/2 kVA的实验样机,并构建7次谐振环境,实验结果验证了复合控制策略阻尼谐振的有效性。
文摘Absrtact: The principle of ZVS - PWM inverting circuit is first described by means of inverting welder supply. The contrastive study is made on switching characte -ristics and switching losses of IGBT between ZVS - PWM and hard - switching.
文摘a Pole voltage waveforms (VA20 and VA40) for modulation index 0.4 (middle trace is A-phase voltage waveform) x-axis: 1 div.=10ms, y-axis: 1 div.= 100V b Normalized harmonic spectrum for pole voltage of Fig. 9a c A-phase current and phase voltage for modulation index 0.4 (reference space vector is in inner layer)
