基于級聯(lián)H橋的STATCOM及其控制策略研究
發(fā)布時間：2018-08-07 08:18
【摘要】：近年來，配電網中迅速增多的非線性、沖擊性及不平衡負荷，帶來了很多電能質量問題。這些問題中尤以無功、諧波及三相不平衡問題最為突出。靜止同步補償器(static synchronous compensator，STATCOM)作為當前最先進的無功補償裝置，可以同時解決上述問題。H橋級聯(lián)型STATCOM因具備諸多優(yōu)點，在配電網中有廣闊的應用前景。本文對H橋級聯(lián)型STATCOM的一些關鍵問題進行了研究。 為使配電網STATCOM具備綜合補償能力，論文首先研究了適用于完全補償的指令電流檢測算法，對其中較常用的p q法、同步旋轉坐標變換法及FBD法進行了分析比較，指出了各自的優(yōu)缺點并給出了相應改進方法。詳細的仿真實驗驗證了上述改進方法的有效性。為使STATCOM能夠提供更加靈活的補償功能，論文還研究了適用于選擇性補償的檢測算法，在分析常用選擇性指令電流檢測算法優(yōu)缺點的基礎上，提出了一種同步旋轉坐標變換及遞歸離散傅立葉變換相結合的檢測算法，仿真實驗證明該算法具有較高的檢測精度及較好的動態(tài)性能。 STATCOM進行綜合補償時，傳統(tǒng)的比例積分(PI)控制很難消除穩(wěn)態(tài)誤差。為此，論文采用諧振控制器來實現指令電流跟蹤控制，為減少控制器數量，選擇在同步旋轉坐標系下應用諧振控制器，分別對基于傳統(tǒng)諧振控制器的PI R控制器及基于矢量比例積分(vector proportion integral，VPI)控制器的PI VPI控制器進行了研究。通過詳細的分析比較，論證了PI VPI控制器的優(yōu)良性能。論文給出了相關參數設計方法，并對VPI控制器的離散化方法進行了詳細分析，得出了最佳的離散化方法。 為了使控制器更加簡化，論文還研究了基于重復控制器的指令電流跟蹤控制策略。為了解決重復控制器動態(tài)響應慢的問題，提出了一種重復控制器與PI控制器串聯(lián)的雙閉環(huán)控制系統(tǒng)。為了解決重復控制器頻率適應性差的問題，采用了一種基于固定采樣點數的軟件鎖相環(huán)策略。仿真結果表明，使用該方法具有很好的補償效果，且頻率適應性很好。 討論了PWM調制策略，通過對比多電平變換器常用的載波移相及載波層疊PWM方法，指出同向載波層疊PWM法具有較好的輸出特性，且相對更加簡單，更易于實際應用。在此基礎上，采用了一種改進的同向載波層疊PWM方法，使用該方法時，載波數量可比采用普通方法減少一半，從而簡化了設計。 針對級聯(lián)型STATCOM直流側電壓的建立過程，論文提出一種軟起控制策略，可使電容電壓從零平穩(wěn)上升到參考值，且整個過程中，裝置都不會產生很大的沖擊電流，從而確保了裝置的安全啟動。針對正常運行過程中的直流側電容電壓均衡控制問題，通過總體控制、相間均壓和相內均壓三種措施來平衡直流側電容電壓，可以很好地解決直流側均壓問題。論文采用零序電壓注入法解決了相間均壓問題。針對采用同向載波層疊PWM方法的STATCOM，本文根據直流側電容電壓的高低實時調整調制波分配規(guī)則，從而實現逆變橋自身能量平衡，，解決了直流側電容相內均壓問題，同時還解決了各功率單元開關頻率不均的問題。最后通過仿真驗證了本文所提方法的有效性。 論文以6kV±3MVar STATCOM為例，對H橋級聯(lián)型STATCOM的軟硬件設計進行了介紹。通過搭建實驗平臺，對裝置的無功補償及諧波補償性能進行了測試，還測試了選擇性補償功能。最后給出了STATCOM裝置投入實際工業(yè)應用的效果。實驗及工程應用表明本文所設計的STATCOM裝置可以取得很好的補償效果，驗證了本文所提控制策略的合理性及可行性。
[Abstract]:In recent years, the rapid increase of nonlinear, impact and unbalanced load in distribution network brings a lot of energy quality problems. Among these problems, the problems of reactive power, harmonic and three-phase unbalance are the most prominent. Static synchronous compensator (STATCOM), as the most advanced reactive power compensation device, can be solved simultaneously. In order to solve the above problems,.H bridge cascaded STATCOM has a wide application prospect in distribution network because of its many advantages. This paper has studied some key problems of cascaded STATCOM with H bridge.
In order to make the distribution network STATCOM have comprehensive compensation ability, this paper first studies the instruction current detection algorithm which is suitable for complete compensation. It compares the common p q method, synchronous rotation coordinate transformation method and FBD method, points out their advantages and disadvantages and gives the improved method. The detailed simulation experiment verifies the above. The effectiveness of the improved method. In order to provide more flexible compensation function for STATCOM, the paper also studies the detection algorithm suitable for selective compensation. On the basis of analyzing the advantages and disadvantages of the commonly used selective instruction current detection algorithm, a detection algorithm combining synchronous rotating coordinate transformation and recursive discrete Fu Liye transform is proposed. Simulation results show that the algorithm has higher detection accuracy and better dynamic performance.
When STATCOM is compensated, the traditional proportional integral (PI) control is difficult to eliminate the steady-state error. Therefore, this paper uses the resonant controller to realize the command current tracking control. In order to reduce the number of controllers, the resonant controller is applied in the synchronous rotating coordinate system, and the PI R controller based on the traditional resonant controller and the vector based on the vector are selected. The PI VPI controller of the proportional integral (vector proportion integral, VPI) controller is studied. Through the detailed analysis and comparison, the excellent performance of the PI VPI controller is demonstrated. The design method of the relevant parameters is given in this paper, and the discrete method of the VPI controller is analyzed in detail, and the best discretization method is obtained.
In order to make the controller more simplified, this paper also studies the command current tracking control strategy based on repetitive controller. In order to solve the problem of slow dynamic response of repetitive controller, a double closed loop control system with repeated controller and PI controller is proposed. In order to solve the problem of frequency adaptability of repetitive controller, a new control system is adopted. A software phase-locked loop (PLL) strategy based on fixed sampling points is proposed. Simulation results show that this method has good compensation effect and good frequency adaptability.
The PWM modulation strategy is discussed. By comparing the carrier phase shift and carrier layer PWM method commonly used in multilevel converters, it is pointed out that the same direction carrier layer PWM method has better output characteristics, and is relatively simpler and more practical. On this basis, an improved same direction carrier stack PWM method is adopted, and the number of carrier number is used when this method is used. The volume can be reduced by half by the common method, thus simplifying the design.
For the establishment of cascaded STATCOM DC side voltage, a soft start control strategy is proposed in this paper, which can make the capacitor voltage rise from zero to the reference value. In the whole process, the device will not produce a large impact current, thus ensuring the safe start of the device. The problem is to balance the DC side capacitance voltage by three measures, including overall control, phase mean pressure and phase mean pressure. The problem of DC side mean voltage can be solved well. The paper adopts zero sequence voltage injection method to solve the problem of interphase mean pressure. In this paper, the high and low voltage of DC side capacitance is based on the STATCOM of the same direction carrier cascading PWM method. The regulation of modulation wave distribution is adjusted to realize the energy balance of the inverter bridge, and the problem of the voltage equalizing in the capacitor phase of the DC side is solved. At the same time, the problem of the switching frequency of each power unit is solved. Finally, the effectiveness of the proposed method is verified by the simulation.
Taking 6kV + 3MVar STATCOM as an example, this paper introduces the hardware and software design of cascade STATCOM of H bridge. By building an experimental platform, the reactive power compensation and harmonic compensation performance of the device are tested, and the selective compensation function is tested. Finally, the effect of the application of the STATCOM device to the actual industrial application is given. The experimental and engineering application tables are given. It is shown that the STATCOM device designed in this paper can achieve good compensation effect, which verifies the rationality and feasibility of the control strategy proposed in this paper.
【學位授予單位】：中國礦業(yè)大學
【學位級別】：博士
【學位授予年份】：2014
【分類號】：TM761
本文編號：2169435
[Abstract]:In recent years, the rapid increase of nonlinear, impact and unbalanced load in distribution network brings a lot of energy quality problems. Among these problems, the problems of reactive power, harmonic and three-phase unbalance are the most prominent. Static synchronous compensator (STATCOM), as the most advanced reactive power compensation device, can be solved simultaneously. In order to solve the above problems,.H bridge cascaded STATCOM has a wide application prospect in distribution network because of its many advantages. This paper has studied some key problems of cascaded STATCOM with H bridge.
In order to make the distribution network STATCOM have comprehensive compensation ability, this paper first studies the instruction current detection algorithm which is suitable for complete compensation. It compares the common p q method, synchronous rotation coordinate transformation method and FBD method, points out their advantages and disadvantages and gives the improved method. The detailed simulation experiment verifies the above. The effectiveness of the improved method. In order to provide more flexible compensation function for STATCOM, the paper also studies the detection algorithm suitable for selective compensation. On the basis of analyzing the advantages and disadvantages of the commonly used selective instruction current detection algorithm, a detection algorithm combining synchronous rotating coordinate transformation and recursive discrete Fu Liye transform is proposed. Simulation results show that the algorithm has higher detection accuracy and better dynamic performance.
When STATCOM is compensated, the traditional proportional integral (PI) control is difficult to eliminate the steady-state error. Therefore, this paper uses the resonant controller to realize the command current tracking control. In order to reduce the number of controllers, the resonant controller is applied in the synchronous rotating coordinate system, and the PI R controller based on the traditional resonant controller and the vector based on the vector are selected. The PI VPI controller of the proportional integral (vector proportion integral, VPI) controller is studied. Through the detailed analysis and comparison, the excellent performance of the PI VPI controller is demonstrated. The design method of the relevant parameters is given in this paper, and the discrete method of the VPI controller is analyzed in detail, and the best discretization method is obtained.
In order to make the controller more simplified, this paper also studies the command current tracking control strategy based on repetitive controller. In order to solve the problem of slow dynamic response of repetitive controller, a double closed loop control system with repeated controller and PI controller is proposed. In order to solve the problem of frequency adaptability of repetitive controller, a new control system is adopted. A software phase-locked loop (PLL) strategy based on fixed sampling points is proposed. Simulation results show that this method has good compensation effect and good frequency adaptability.
The PWM modulation strategy is discussed. By comparing the carrier phase shift and carrier layer PWM method commonly used in multilevel converters, it is pointed out that the same direction carrier layer PWM method has better output characteristics, and is relatively simpler and more practical. On this basis, an improved same direction carrier stack PWM method is adopted, and the number of carrier number is used when this method is used. The volume can be reduced by half by the common method, thus simplifying the design.
For the establishment of cascaded STATCOM DC side voltage, a soft start control strategy is proposed in this paper, which can make the capacitor voltage rise from zero to the reference value. In the whole process, the device will not produce a large impact current, thus ensuring the safe start of the device. The problem is to balance the DC side capacitance voltage by three measures, including overall control, phase mean pressure and phase mean pressure. The problem of DC side mean voltage can be solved well. The paper adopts zero sequence voltage injection method to solve the problem of interphase mean pressure. In this paper, the high and low voltage of DC side capacitance is based on the STATCOM of the same direction carrier cascading PWM method. The regulation of modulation wave distribution is adjusted to realize the energy balance of the inverter bridge, and the problem of the voltage equalizing in the capacitor phase of the DC side is solved. At the same time, the problem of the switching frequency of each power unit is solved. Finally, the effectiveness of the proposed method is verified by the simulation.
Taking 6kV + 3MVar STATCOM as an example, this paper introduces the hardware and software design of cascade STATCOM of H bridge. By building an experimental platform, the reactive power compensation and harmonic compensation performance of the device are tested, and the selective compensation function is tested. Finally, the effect of the application of the STATCOM device to the actual industrial application is given. The experimental and engineering application tables are given. It is shown that the STATCOM device designed in this paper can achieve good compensation effect, which verifies the rationality and feasibility of the control strategy proposed in this paper.
【學位授予單位】：中國礦業(yè)大學
【學位級別】：博士
【學位授予年份】：2014
【分類號】：TM761
【參考文獻】
相關期刊論文 前10條
1 梁旭,劉文華,陳建業(yè),王仲鴻;基于多重化逆變器的靜止無功發(fā)生器直流側電流分析[J];電工技術學報;2000年01期
2 單慶曉,李永東,潘孟春;級聯(lián)型逆變器的新進展[J];電工技術學報;2004年02期
3 楊秋霞;梁雄國;郭小強;趙清林;;準諧振控制器在有源電力濾波器中的應用[J];電工技術學報;2009年07期
4 劉文華,劉炳;IEGT——適用于STATCOM的新型大功率開關器件[J];電力電子技術;2001年04期
5 諸紀新;;±50 Mvar STATCOM裝置在上海電網中的應用[J];電力建設;2006年12期
6 劉文華,梁旭,姜齊榮,羅承廉,劉遵義;采用GTO逆變器的±20 Mvar STATCOM[J];電力系統(tǒng)自動化;2000年23期
7 劉文華,劉炳,王志泳,盧軍鋒,王京民;基于IGBT三電平逆變器的±100kvarD—STATCOM[J];電力系統(tǒng)自動化;2002年01期
8 朱桂萍,王樹民;電能質量控制技術綜述[J];電力系統(tǒng)自動化;2002年19期
9 耿俊成,劉文華,袁志昌;鏈式STATCOM電容電壓不平衡現象研究(一)仿真和試驗[J];電力系統(tǒng)自動化;2003年16期
10 耿俊成,劉文華,袁志昌;鏈式STATCOM電容電壓不平衡現象研究(二)數學模型[J];電力系統(tǒng)自動化;2003年17期
相關博士學位論文 前5條
1 謝斌;并聯(lián)型有源電力濾波器諧波檢測及控制技術研究[D];華中科技大學;2010年
2 漆銘鈞;注入式混合型有源電力濾波器關鍵技術研究及其工程實現[D];湖南大學;2010年
3 仇志凌;基于LCL濾波器的三相三線并網變流器若干關鍵技術研究[D];浙江大學;2009年
4 苗長新;中壓級聯(lián)型多電平STATCOM關鍵技術研究[D];中國礦業(yè)大學;2012年
5 謝川;數字控制大容量并聯(lián)型APF關鍵技術研究[D];浙江大學;2012年
本文編號：2169435
本文鏈接：http://www.sikaile.net/kejilunwen/dianlilw/2169435.html
