电动汽车充电站的谐波分析与抑制

以某种型号电动汽车充电机构成的充电站为例,在Matlab／Simulink下仿真,结合实测数据分析充电站在电网上产生谐波的特点,有针对性地提出若干治理措施,分别进行仿真实验。结果表明,几种方案可以有效地抑制充电站对电网造成的5,7次谐波。     

基于改进烟花算法的电动汽车与新能源协同调度

为提高电力系统对新能源出力的接纳能力,降低区域电网的等效负荷波动,维护系统安全性的同时,增强电动车车主响应的积极性,以区域电网系统内的等效负荷波动量最小和电动车车主经济效益最优为优化目标,建立规模化电动汽车与新能源协同调度模型,来合理安排电动汽车的充放电行为。运用最大模糊满意度法将多目标问题化为单目标问题,提出一种改进烟花算法,通过优化初始种群分布,以“双精英—锦标赛”的选择策略提升算法性能。通过算例结果对比,验证规模化电动汽车与新能源协同调度可有效平抑等效负荷波动,为电动汽车用户创造收益。改进的算法降低了计算开销,求解精确度更高。     

Operation Strategy of EV Battery Charging and Swapping Station

An operation strategy of the electric vehicle (EV) battery charging and swapping station is proposed in the paper. The strategy is established based on comprehensively consideration of the EV charging behaviors and the possible mutual actions between battery charging and swapping. Three energy management strategies can be used in the station: charging period shifting, energy exchange between EVs, and energy supporting from surplus swapping batteries. Then an optimization model which minimizes the total energy management costs of the station is built. The Monte Carlo simulation is applied to analyze the characteristics of the EV battery charging load, and a heuristic algorithm is used to solve the strategy providing the relevant information of EVs and the battery charging and swapping station. The operation strategy can efficiently reduce battery charging during the high electricity price periods and make more reasonable use of the resources. Simulations prove the feasibility and rationality of the strategy.     

基于瞬时无功理论的谐波检测方法研究

谐波检测方法在有源电力滤波器中起着关键作用,分析了基于瞬时无功理论的ipiq谐波检测方法的基本原理,并把他推广到任意次谐波的检测。仿真结果表明这种检测方法具有很好的稳态精度和动态性能,即使在电网频率变化的情况下,采用频率跟踪技术后ipiq法也可以快速准确地检测出电网总体谐波或任意次谐波分量。     

煤矿电网谐波检测方法与治理方案

针对煤矿电网中高次谐波状况,设计出一种基于希尔伯特黄变换电网谐波检测的方法与治理方案。以煤矿6kV电网为例,用MATLAB软件建立串联联结的6脉冲整流电路模型模拟谐波,由控制芯片TMS320F2812完成电压电流信号采集,并根据希尔伯特边际谱得到各次谐波含量,将该谐波含量与换算国家标准对比,根据对比结果建立混合型有源滤波器模型模拟滤波,结果表明了该系统的有效性和可行性。     

Advanced concepts in electric vehicle design

In 1994, the Eco-Vehicle Project was begun to develop an electric vehicle (EV) using a ground-up design approach that incorporates unique designs specific to an EV. The Eco-Vehicle will be a high-performance, but ultrasmall, battery-powered vehicle. New designs for the Eco-Vehicle include an in-wheel motor drive system, a hollow load floor which will house the batteries, and a new battery management system. The Eco-Vehicle may also utilize other advanced concepts suitable especially for EVs, including solar panels for battery charging and intelligent crash avoidance and guidance systems     

三相PWM整流器在电动汽车充电机上的应用

本文对电动汽车充电机的功率电路拓扑结构进行了设计,详细分析了三相PWM整流电路的工作原理。同时针对充电机的特点对功率因数、充电效率等方面的性能做了优化,并结合实际电路对控制方法进行了改进。利用MATLAB/SIMULINK工具对电路拓扑和控制方法进行了仿真,仿真结果表明:设计的方法正确,软开关技术有效;与传统整流器相比,直流侧电压稳定脉动小,交流侧电流接近正弦,而且电压电流相位一致,能够极大的提高功率因数,同时充电的效率能够达到设计的要求。     

基于复调制细化谱分析的轧辊偏心谐波参数估计

针对轧辊的上、下支撑辊偏心信号是密集型频谱的特点,提出了一种基于复调制细化谱分析方法的轧辊偏心谐波参数估计新方法。利用复调制细化谱分析方法准确估计出偏心谐波的频率及幅值;同时,结合快速傅里叶变换算法估计出偏心谐波的相角参数。仿真实验结果验证了该方法在偏心谐波参数估计上的有效性和可行性。     

Electric vehicles-architecting the system

Standardized charging hardware and procedures that must be put in place before the first electric vehicles (EVs) go on sale in the mid-90s are discussed. Other requirements considered include charging installations, facilities for replacing and recycling batteries, training and deployment of technicians for emergency road service and for manning quick-charge stations, training for police and firefighting personnel on dealing with EV accidents, appropriate electrical system capacity, appropriate rate structures, and public education     

Adaptive neuro-fuzzy modeling of battery residual capacity forelectric vehicles

This paper proposes and implements a new method for the estimation of the battery residual capacity (BRC) for electric vehicles (EVs). The key of the proposed method is to model the EV battery by using the adaptive neuro-fuzzy inference system. Different operating profiles of the EV battery are investigated including the constant current discharge and the random current discharge as well as the standard EV driving cycles in Europe, the US, and Japan. The estimated BRCs are directly compared with the actual BRCs, verifying the accuracy and effectiveness of the proposed modeling method. Moreover, this method can be easily implemented by a low-cost microcontroller and can readily be extended to the estimation of the BRC for other types of EV batteries     

电动汽车交流充电桩的电磁兼容测试研究

电动汽车交流充电桩是电动汽车发展的重要组成部分,该文主要针对交流充电桩的电磁兼容方面,对其验收的规范要求和测试的方法进行了研究和介绍.     

Design considerations and topology selection for a 120-kW IGBTconverter for EV fast charging

Fast charging of electric vehicles (EVs) is a very desirable feature, especially for long-distance travel. For an EV with a battery capacity of 30 kWh, a 15-min charge requires 120-kW charging power. Inductive charging offers a safe and convenient means to accomplish this task. This paper investigates the design criteria of the high-power converter for a 120-kW inductive battery charger. Since insulated gate bipolar transistors (IGBTs) are the devices of choice at this power level, the impact of IGBT losses on the converter design and topology selection is investigated. A comparison between a zero-voltage-switching (ZVS) and zero-current-switching (ZCS) series-resonant converter (SRC) is presented. Based on the comparison results, a ZCS SRC topology is selected for this application, and an experimental 120-kW/75-kHz unit was built and tested in the laboratory to verify the results     

An overview of power electronics in electric vehicles

In response to concerns about energy cost, energy dependence, and environmental damage, a rekindling of interest in electric vehicles (EVs) has been obvious. Based on the “California rules” on zero emission vehicles in the United States, as well as similar tightened air pollution regulation in Europe, Asia, and much of the rest of the world, the market size of EVs will be enormous. Thus, the development of power electronics technology for EVs will take an accelerated pace to fulfil the market needs. This paper reviews the current status of multidisciplinary technologies in EVs. Various challenges of power electronics technology for EV propulsion, battery charging, and power accessories are explored     

基于神经网络的单相Boost—PFC变换器的设计

文章在分析了传统的PFC变换器控制原理后,针对滤波过程使用低通滤波器带来的带宽限制,提出了一种新的控制方法,能在PFC变换器中克服带宽的限制,从而提高输出电压的动态响应。该方法用一个比较器取代低通滤波器,并应用一个多层前馈神经网络（MLFNN）来精确估计谐波成分。通过Matlab仿真表明,由神经网络控制的变换器,在没有滤波装置的情况下,也能消除直流电压反馈路径中的纹波电压和瞬态输出电压正尖峰和负尖峰,从而允许大带宽设计电压控制回路。同时,通过数字信号处理器实现的系统实验验证了该方案的正确性。     

A Carrier-Transit-Delay-Based Nonquasi-Static MOSFET Model for Circuit Simulation and Its Application to Harmonic Distortion Analysis

In this paper, a compact model of nonquasi-static (NQS) carrier-transport effects in MOSFETs is reported, which takes into account the carrier-response delay to form the channel. The NQS model, as implemented in the surface-potential-based MOSFET Hiroshima University STARC IGFET model, is verified to predict the correct transient terminal currents and to achieve a stable circuit simulation. Simulation results show that the NQS model can even reduce the circuit simulation time in some cases due to the elimination of unphysical overshoot peaks normally calculated by a QS-model. An average additional computational cost of only 3% is demonstrated for common test circuits. Furthermore, harmonic distortion characteristics are investigated using the developed NQS model. While the distortion characteristics at low drain bias and low switching frequency are determined mainly by carrier mobility, distortion characteristics at high frequency are found to be strongly influenced by channel charging/discharging.     

V2G模式下的EV建模研究

风电并网规模的不断扩大给电力系统的稳定运行带来了巨大的挑战.针对不断增加的SR需求,提出了将EV作为SR调度的研究方法.文中对EV的充放电特性进行了分析及仿真,并采用成本效益分析法建立了系统发电成本、备用成本和EV调度成本之和最小的目标函数.采用蒙特卡洛模拟对V2G模式下的EV进行仿真,考虑分时电价策略,确定出了最佳的...     

有源滤波器多目标检测策略建模研究

针对有源滤波器多个控制目标的趋势,本文采用一种能在不对称和电网电压存在畸变条件下准确提取电网中谐波或无功电流的检测方法,并搭建了PSCAD仿真模型。该模型从矢量分析角度出发,通过对三相电网电压和电流矢量在d-q坐标系下进行投影变换,实现了谐波和无功电流任意组合的提取。仿真结果验证了多目标检测策略的检测精度,该多目标检测策略也大大简化了对多目标有源滤波器的控制策略设计,模型具有很强的实用价值。     

IMAGING OF EEG BY SPHERICAL HARMONIC ANALYSIS

A new three dimensional imaging method for electroencephalogram(EEG) is suggested. It consists of the solution of an inward spherical harmonic continuation. The principle of the new method is introduced in Section II, then a few numerical simulation tests are shown and the feasibility of the new method is confirmed by the simulation results.     

Neural network-based residual capacity indicator for nickel-metal hydride batteries in electric vehicles

This paper presents a new estimation approach for the battery residual capacity (BRC) indicator in electric vehicles (EVs). The key of this approach is to model the EV battery by using a neural network (NN) with a newly defined output and newly proposed inputs. The inputs are the discharged and regenerative capacity distribution and the temperature. The output is the state of available capacity (SOAC) which represents the BRC. Various SOACs of the nickel-metal hydride (Ni-MH) battery are experimentally investigated under different EV discharge current profiles and temperatures. The corresponding data are recorded to train and verify the proposed NN. The results indicate that the NN can provide an accurate and effective estimation of the BRC. Moreover, this NN can be easily implemented as the BRC indicator or estimator for EVs by using a low-cost microcontroller.     

Failsafe Drive Performance of FRID Electric Vehicles With the Structure Driven by the Front and Rear Wheels Independently

Failsafe performance is clarified for electric vehicles (EVs) with the drive structure driven by front and rear wheels independently, i.e., front and rear wheel independent drive type (FRID) EV. A simulator based on the four-wheel vehicle model, which can be applied to various types of drive systems like four in-wheel motor-drive-type EVs, is used for the clarification. Yaw rate and skid angle, which are related to drivability and steerability of vehicles and which further influence the safety of vehicles during runs, are analyzed under the condition that one of the motor drive systems fails while cornering on wet roads. In comparison with the four in-wheel motor-drive-type EVs, it is confirmed that the EVs with the structure focused in this paper have little change of the yaw rate and that hardly any dangerous phenomena appear, which would cause an increase in the skid angle of vehicles even if the front or rear wheel drive systems fail when running on wet roads with low friction coefficient. Moreover, the failsafe drive performance of the FRID EVs with the aforementioned structure is verified through experiments using a prototype EV.