Design of DC Side Voltage and Compensation Analysis of THD for Shunt Power Quality Controller under System Load of Rectifier with R-L Load

Guopeng Zhao,Minxiao Han 대한전기학회 2015 Journal of Electrical Engineering & Technology Vol.10 No.1

For a shunt power quality controller (SPQC) the DC side voltage value which is closely related to the compensation performance is a significant parameter. Buy so far, very little discussion has been conducted on this in a quantitative manner by previous publications. In this paper, a method to design the DC side voltage of SPQC is presented according to the compensation performance in the single-phase system and the three-phase system respectively. First, for the reactive current and the harmonic current compensation, a required minimal value of the DC side voltage with a zero total harmonic distortion (THD) of the source current and a unit power factor is obtained for a typical load, through the equivalent circuit analysis and the Fourier Transform analytical expressions. Second, when the DC side voltage of SPQC is lower than the above-obtained minimal value, the quantitative relationship between the DC side voltage and the THD after compensation is also elaborated using the curve diagram. Hardware experimental results verify the design method.

Design of DC Side Voltage and Compensation Analysis of THD for Shunt Power Quality Controller under System Load of Rectifier with R-L Load

Zhao, Guopeng,Han, Minxiao The Korean Institute of Electrical Engineers 2015 Journal of Electrical Engineering & Technology Vol.10 No.1

For a shunt power quality controller (SPQC) the DC side voltage value which is closely related to the compensation performance is a significant parameter. Buy so far, very little discussion has been conducted on this in a quantitative manner by previous publications. In this paper, a method to design the DC side voltage of SPQC is presented according to the compensation performance in the single-phase system and the three-phase system respectively. First, for the reactive current and the harmonic current compensation, a required minimal value of the DC side voltage with a zero total harmonic distortion (THD) of the source current and a unit power factor is obtained for a typical load, through the equivalent circuit analysis and the Fourier Transform analytical expressions. Second, when the DC side voltage of SPQC is lower than the above-obtained minimal value, the quantitative relationship between the DC side voltage and the THD after compensation is also elaborated using the curve diagram. Hardware experimental results verify the design method.

Analysis and Design of the Interface Inductor and the DC Side Capacitor in a STATCOM with Phase and Amplitude Control Considering the Stability of the System

Zhao, Guopeng,Han, Minxiao,Liu, Jinjun The Korean Institute of Power Electronics 2012 JOURNAL OF POWER ELECTRONICS Vol.12 No.1

Previous publications regarding the design and specifications of the interface inductor and the DC side capacitor for a STATCOM usually deal with the interface inductor and the DC side capacitor only. They seldom pay attention to the influences of the interface inductor and capacitor on the performance of a STATCOM system. In this paper a detailed analysis of influence of the interface inductor and the DC side capacitor on a STATCOM system and the corresponding design considerations is presented. Phase and amplitude control is considered as the control strategy for the STATCOM. First, a model of a STATCOM system is carried out. Second, through frequency domain methods, such as transfer functions and Bode plots, the influence of the interface inductor and the DC side capacitor on the stability and filtering characteristics of the STATCOM are extensively investigated. Third, according to this analysis, the design considerations based on the phase margin for the interface inductor and the DC side capacitor are discussed, which leads to parameters that are different from those of the traditional design.

Analysis and Design of the Interface Inductor and the DC Side Capacitor in a STATCOM with Phase and Amplitude Control Considering the Stability of the System

Guopeng Zhao,Minxiao Han,Jinjun Liu 전력전자학회 2012 JOURNAL OF POWER ELECTRONICS Vol.12 No.1

Previous publications regarding the design and specifications of the interface inductor and the DC side capacitor for a STATCOM usually deal with the interface inductor and the DC side capacitor only. They seldom pay attention to the influences of the interface inductor and capacitor on the performance of a STATCOM system. In this paper a detailed analysis of influence of the interface inductor and the DC side capacitor on a STATCOM system and the corresponding design considerations is presented. Phase and amplitude control is considered as the control strategy for the STATCOM. First, a model of a STATCOM system is carried out. Second, through frequency domain methods, such as transfer functions and Bode plots, the influence of the interface inductor and the DC side capacitor on the stability and filtering characteristics of the STATCOM are extensively investigated. Third, according to this analysis, the design considerations based on the phase margin for the interface inductor and the DC side capacitor are discussed, which leads to parameters that are different from those of the traditional design.

Design of Input Filters Considering the Stability of STATCOM Systems

Zhao, Guopeng,Liu, Jinjun,Han, Minxiao The Korean Institute of Power Electronics 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.6

Previous publications regarding the design and specifications of input filters for STATCOMs usually deal with the input filter only, and seldom pay any attention to the influence of the input filters on the performance of the STATCOM systems. A detailed analysis of the influences of input filters on the stability of STATCOM systems and the corresponding design considerations are presented in this paper. Three types of input filters, L filters, LC filters, and LCL filters, are examined separately. The influences of the parameters of input filters on system stability are investigated through frequency domain methods. With direct current control taken as the major control strategy for the STATCOMs, the different situations when adopting different current detection points are covered in this analysis. A comparison between LC filters and LCL filters is also presented with optimized filter parameters. Based on the analysis, the phase margin, as one of the design considerations for the different types of input filters under different current detection schemes, is discussed. This leads to filter parameters that are different than those of the traditional design. Hardware experimental results verify the validity of the above analysis and design.

Analysis and Control of an MMC-HVDC System Under an Unbalanced Grid Condition

Kim Tuan Luu,Minxiao HAN,Senior Member, IEEE,Xiaojun Tang 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.6

Modular multilevel converter (MMC)-based high voltage direct current (HVDC) systems have been increasingly researched and installed in recent years. During operation, systems may be subjected to various unbalanced conditions, the single-line to ground (SLG) fault is one of the most common unbalanced faults. When a SLG fault occurs in a three-phase alternating current (AC) system, the double-line frequency positive- and zero-sequence harmonic components will be produced besides the double-line frequency negative-sequence harmonic component. And if the control system cannot suppress these harmonic components, they can propagate into the direct current (DC) side of the HVDC system and cause ripples in DC-line voltage and current as well as other unwanted consequences. Among the proposed controllers in the published papers on this topic, rarely controllers can both eff ectively suppress the circulating current and completely eliminate ripples in the DC-line voltage and current while still keeping the AC-side current balanced under unbalanced grid conditions. Therefore, this paper fi rst analyses the propagation of harmonic components in a two-terminal MMC-HVDC system under a SLG fault. Then, based on the mathematical analysis, a proposed controller including an inner current controller for controlling the negativeand positive-sequence components and a controller for suppressing the zero-sequence component is designed to eliminate harmonic propagation from the faulty three-phase AC system to the DC side of the HVDC system, resulting in suppressing ripples in DC-line voltage and current. The theoretical analysis and proposed controller are verifi ed by a simulation model in PSCAD platform.

Design of Input Filters Considering the Stability of STATCOM Systems

Guopeng Zhao,Jinjun Liu,Minxiao HAN 전력전자학회 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.6

Previous publications regarding the design and specifications of input filters for STATCOMs usually deal with the input filter only, and seldom pay any attention to the influence of the input filters on the performance of the STATCOM systems. A detailed analysis of the influences of input filters on the stability of STATCOM systems and the corresponding design considerations are presented in this paper. Three types of input filters, L filters, LC filters, and LCL filters, are examined separately. The influences of the parameters of input filters on system stability are investigated through frequency domain methods. With direct current control taken as the major control strategy for the STATCOMs, the different situations when adopting different current detection points are covered in this analysis. A comparison between LC filters and LCL filters is also presented with optimized filter parameters. Based on the analysis, the phase margin, as one of the design considerations for the different types of input filters under different current detection schemes, is discussed. This leads to filter parameters that are different than those of the traditional design. Hardware experimental results verify the validity of the above analysis and design.