【摘要】：V2G(Vehicle to Grid)是指電動汽車與智能電網之間進行能量與信息雙向傳遞的技術。具備V2G功能的電動汽車可以在兼顧自身性能的前提下,向電網提供調峰、調頻、無功補償、旋轉備用等服務。雙向充電機是電動汽車向電網提供V2G服務的重要物理媒介。目前適用于V2G服務的車載雙向充電機是智能電網與電動汽車能量管理的一個研究熱點。由于V2G模式要求充電機不僅具有充電功能,還有向電網饋電的功能,與電網互動時需要較寬的功率輸出范圍內實現高效運行,提高動態(tài)響應速度,而且大規(guī)模運行時對于諧波要求更嚴。本文對V2G用車載式充電機及其諧波與效率問題進行研究。基于上述要求對3.3k W的兩級式車載雙向充電機進行了設計。前級AC-DC變換器采用單相PWM整流電路,后級DC-DC變換器采用雙向有源橋式電路。在V2G調頻信號控制下,充電機的輸出功率范圍會變寬,輕載時電流紋波比例變大與電流響應速度變慢而引起過零點畸變。傳統的控制器穩(wěn)態(tài)誤差也會增加。這些問題都會導致網側電流諧波含量變大導致電能質量下降。本文給出了準PR控制與電流加權法的網側電流控制方法,并和傳統的分段PI控制等其他幾種控制方法的諧波抑制效果行了對比,通過Simulink仿真與實驗證明了PR與電流加權復合控制可以將網側諧波限制在0.32%左右,并提高了系統的動態(tài)響應速度。充電機的DC-DC變換器輕載時拓撲中的諧振能量變弱,開關損耗會加劇,使充電機在寬范圍輸出功率運行時的平均效率偏低。針對這一問題,本文采用了PWM-SPS控制拓展軟開關范圍,提高DC-DC變換器輕載效率。此外PWM-SPS控制還可以減少DC-DC變換器的高頻變壓器電流,緩解器件的電流應力,提高系統的可靠性。從實驗數據和曲線中可以看出PWM-SPS控制相對于傳統的移相控制的充電機效率優(yōu)勢,額定效率達到95%以上,輕載效率提高了6%左右。此外本文還研究了車載雙向充電機在傳統的充電模式中以及V2G模式的充放電過程的AC-DC變換器與DC-DC變換器的控制配合問題,以及控制充電機向電網回饋有功功率與無功功率的方案。最后通過改進LCL濾波器的結構抑制了諧振頻率振蕩尖峰,并設計了帶有緩沖的驅動電路解決了一部分實驗過程中遇到的充電機開關管驅動電路受到干擾以及死區(qū)振蕩等電磁兼容問題。
[Abstract]:V2G (Vehicle to Grid) refers to the two-way transmission of energy and information between electric vehicles and smart grids. The electric vehicle with V2G function can provide peak shaving, frequency modulation, reactive power compensation, rotating standby and other services to the power grid on the premise of taking into account its own performance. Two-way charger is an important physical medium for electric vehicles to provide V 2 G service to power grid. At present, vehicle bidirectional charger suitable for V2G service is a research hotspot in smart grid and electric vehicle energy management. Since the V2G mode requires that the charger not only has charging function, but also the function of feeding to the power grid, it needs a wide range of power output to achieve efficient operation and improve the dynamic response speed when interacting with the power grid. And large-scale operation for harmonic requirements are more stringent. In this paper, the harmonic and efficiency problems of V 2 G car-mounted charger are studied. Based on the above requirements, a two-stage car-mounted bidirectional charger with 3.3 kW is designed. Single phase PWM rectifier is used in the front AC-DC converter and bidirectional active bridge circuit is used in the back stage DC-DC converter. Under the control of V2G frequency modulation signal, the output power range of the charger will become wider, and the current ripple ratio will become larger and the current response speed will slow down, which will lead to zero crossing distortion. The steady-state error of traditional controller will also increase. These problems will lead to the increase of current harmonics on the grid side, which will lead to the decline of power quality. In this paper, the current control methods of quasi-PR control and current-weighted method are given, and the harmonic suppression effects of other control methods, such as traditional piecewise PI control, are compared. Through Simulink simulation and experiment, it is proved that PR and current-weighted composite control can limit the harmonics of the network side to about 0.32%, and improve the dynamic response speed of the system. The resonant energy in the topology of the DC-DC converter becomes weaker when the load is light, and the switching loss will be aggravated, which makes the average efficiency of the charger low when the output power is wide range. To solve this problem, PWM-SPS control is used to expand the range of soft switching and improve the efficiency of light load of DC-DC converter. In addition, PWM-SPS control can also reduce the high frequency transformer current of DC-DC converter, alleviate the current stress of the device, and improve the reliability of the system. From the experimental data and curves, it can be seen that the efficiency of PWM-SPS control is better than that of traditional phase shift control, the rated efficiency is over 95%, and the efficiency of light load is increased by about 6%. In addition, the control and coordination of AC-DC converter and DC-DC converter in traditional charging mode and V2G mode are also studied in this paper. And the scheme of controlling the charging machine to feedback the active power and reactive power to the power grid. Finally, the resonant frequency oscillation peak is restrained by improving the structure of LCL filter. The drive circuit with buffer is designed to solve the electromagnetic compatibility problems such as interference of switch drive circuit and dead-time oscillation encountered in some experiments.
【學位授予單位】：哈爾濱工業(yè)大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：U469.72;TM910.6

【參考文獻】

相關期刊論文 前3條

1 吳鳳江,孫力,高晗瓔,王有琨;橋式驅動功率MOSFET的電磁干擾與抑制[J];南京航空航天大學學報;2005年01期

2 周華偉;溫旭輝;趙峰;張劍;郭新華;;一種新穎的電壓源逆變器自適應死區(qū)補償策略[J];中國電機工程學報;2011年24期

3 周娟;張勇;耿乙文;伍小杰;;四橋臂有源濾波器在靜止坐標系下的改進PR控制[J];中國電機工程學報;2012年06期

相關碩士學位論文 前4條

1 曹琦琦;V2G建模及接入系統分析研究[D];北京交通大學;2011年

2 劉鑫;5kW移相全橋ZVSDC/DC變換器的研究[D];哈爾濱工業(yè)大學;2011年

3 張宏坡;基于V2G應用的車載充放電機的研究與設計[D];華南理工大學;2012年

4 楊敏;PWM加移相控制雙有源全橋雙向DC-DC變換器的研究[D];南京航空航天大學;2013年

，

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