基于MMC的同相供电潮流控制器控制策略研究

模块化多电平换流器(MMC)与平衡变压器相结合的潮流控制器(PFC),可节省传统牵引供电系统中的匹配变压器,满足高压大功率的应用。首先介绍了系统工作原理,重点研究了其中单相MMC背靠背换流器两端的补偿电流。提出了一种综合控制策略,包括变流器两端补偿电流的提取算法,子模块电容电压均衡控制,环流抑制策略以及PWM调制方法。最后在Matlab/Simulink中搭建了系统模型,分别对交直交型电力机车的牵引和再生制动工况进行仿真,验证了所提控制策略的有效性。     

Analysis of electromagnetic processes in the traction network under the interaction of electric locomotives in the regeneration and traction modes

An analysis of the results of simulation of electromagnetic processes in the “traction substation-catenary-electric locomotive” system with electric locomotives working in the feed zone in the traction and regenerative braking modes at different distances from the traction substation is carried out. A real-time computing complex was used for simulation. The mutual influence of electric locomotives and dispensing of active and reactive power was reviewed.     

电力机车励磁涌流消除系统的研究

针对电力机车过分相区时合闸励磁涌流对电力机车及牵引网的电能质量造成的影响,提出了一种基于大功率电力电子技术的电力机车励磁涌流消除系统原理,并提出了同相调幅法和变频移相法两种PWM调制电压算法。该系统通过控制新型大功率电力电子电路整流、逆变、变频模式及机车变压器不同时刻励磁电压,实现电力机车无冲击平滑换相通过分相区,在出分相区合闸瞬间不产生冲击性励磁涌流。利用所提方法建立了该电力机车变压器分区换相系统的仿真模型。通过仿真分析表明,所提出的两种电压调制算法,均能有效抑制合闸励磁涌流的产生,验证了所提方法的可行性。     

列车再生制动能量管理及控制系统研究

为回收利用交流电气化铁路列车产生的再生制动能量,研究了再生制动能量管理及控制系统。提出一种基于牵引负荷状态的能量综合管理策略,以牵引变压器两供电臂负荷功率为信息载体表示系统的不同工作模式,多种工作模式可相互切换。在混合储能装置内部功率分配中,通过引入锂电池荷电状态SOC（state of charge）及超级电容中间调节电压,保证了储能单元能够根据各自储能特性运行。设计了铁路功率调节器RPC（railway power conditioner）变换器和储能接口双向DC/DC变换器的控制算法。仿真结果表明该系统的正确性和有效性。     

基于多目标综合控制的低碳轨道交通操控节能方案

提出一种应用于轨道交通供电系统的多目标综合控制节能方案。采用可控高功率因数整流的AC/DC变流模块取代传统的整流电路以实现能量的双向流动,并采用多个AC/DC变流模块并联的形式来扩大整个方案容量,同时在直流牵引母线处装有一台或多台并联DC/DC变流模块,使机车制动时产生的电能可部分通过AC/DC模块回馈到电网,部分通过DC/DC模块升压后存储到独立电容器组。研究表明,该方案不仅可以充分回收及利用制动能量,并通过部分吸收回馈能量来克服所有能量瞬时回馈电网对电网的冲击,还可以通过对牵引变电站谐波及无功的补偿改善轨道交通变电站的电能质量,从各个角度提升节能功效。     

Control of the traction electric drive of a hybrid shunting locomotive with asynchronous motors in the realization of critical forces

The peculiarities of the structure and regulation of an electric traction drive of the TEM9H prototype four-axle hybrid shunting locomotive, which has two-axle bogies and is connected in parallel asynchronous traction motors to one inverter, are considered. Using very dynamic algorithms for a discontinuous control of asynchronous motors in the regulation of the flux linkage of the stator and the electric battery with a large energy level and superconductors allows one to do without free diesel power for traction to adjust the force of traction required by law, applying the new algorithms of the maximum tractive and braking efforts. The pilot locomotive does not include inclined rods or special loaders to balance the vertical load of the axles of the locomotive, whereby the difference in vertical loads between the bogies of the locomotive is about 6 t at the nominal electromagnetic torque of the motor. Promising control algorithms of a traction electric drive of the TEM9H hybrid shunting locomotive with the joint regulation of asynchronous motors, allowing us to compensate for deficiencies in the design of the running gears and to ensure that the potential of adhesion is not less than 90% in a mode with maximum exertion, are analyzed on the basis of computer simulation.     

Analysis of electromagnetic processes in a homogeneous long line

Dependences between the currents and voltages at terminals of a homogeneous long line were analyzed. They make it possible to more correctly explain the changes in current and voltage in an electric-traction network when switching the thyristor arms of a rectifier–inverter converter than do conclusions obtained during replacement of a long line with a circuit with lumped parameters. An imitation model of the homogeneous low-loss long line in the MATLAB/Simulink software environment is proposed that adequately represents the propagation of incident and reflected electromagnetic waves along the line. Transfer functions are presented that approximate the frequency dependences of the specific parameters of the equivalent rail–ground loop and the overhead catenary–ground loop calculated taking into account the increase in the resistance of the wires due to the eddy currents and the surface effect. The influence of frequency dependences of the specific electric parameters of an electric-traction network calculated by various methods on the free voltage oscillation decay on the electric locomotive pantograph obtained by modeling the electromagnetic processes in the traction substation–electric traction network–electric locomotive system is revealed.     

Calculation of capacitor power accumulators for underground cars

A method of calculating the capacity of capacitor power accumulators is proposed that is installed directly on underground cars to receive power of traction electric equipment operating in the mode of regenerative braking.     

Performance indices of stationary energy storage in the traction substations of the Moscow Metro

It is shown that full-scale application of regenerative breaking in electric trains with asynchronous motors is has a large effect on electric-power efficiency in the traction power-supply system of the Moscow Metro. Particular lines of the Moscow Metro were considered (Filevskaya, Arbatsko-Pokrovskaya, Butovskaya, Kol’tsevaya), where trains are equipped with asynchronous motors of 81–740/741 Rusich series. The lines are able to save up to 10–12% of the traction energy in the regenerated energy. It is suggested to use a system of stationary energy storage to improve the efficiency of regenerative braking. A stationary uncontrolled storage system based on storage modules produced by the Russian company Elton was selected from among the multiple existing types of storage systems. A scheme of stationary energy-storage system for use in the traction power-supply system of the Moscow Metro is described. Electrotechnical characteristics of the storage system and its performance features and functionality are presented. The power indices of the stationary energy-storage system were measured experimentally for normal operation at a traction substation of the Filevskaya line of the Moscow Metro over several months. Maximum levels of the regenerated energy and the cycle and efficiency ratio were determined. Long-term monitoring of the normal operation confirmed high reliability of stationary energy storage. Every system, including the switching elements; diagnostic and control systems of storage modules; and control and signaling systems, including those at the dispatching office; operated in a failsafe fashion. The stationary energy-storage system exhibited more positive effects, such as stabilization of voltage at the traction substation bus and possible lower rated power capacity of a traction substation as an effect of a smooth power consumption. It is also possible to bring a train containing passengers from a tunnel to the nearest station in case of external power-supply failure. The correlation between the theoretical calculations and the experimental measurements is displayed.     

A Multi-Functional Single-Stage Power Electronic Interface for Plug-In Electric Vehicles Application

This paper proposes a Zeta-derived non-isolated single-stage power electronic interface for on-board application of plug-in electric vehicles, which provides all modes (plug-in charging, propulsion, and regenerative braking) of vehicle operation. In addition, the proposed converter can charge the battery through universal input voltage range, i.e., 90–260 V due to buck/boost operations in plug-in charging mode. In propulsion and regenerative braking modes, the proposed converter operates as conventional boost and buck DC/DC converter, respectively. Compared to existing single-stage converters, the proposed converter has least components to those converters which have buck/boost operation in plug-in charging mode. A voltage/current stresses and loss analysis of the converter have been investigated for each mode of converter operation. Detailed simulation and experimental results are given to show the effectiveness of the proposed converter.     

Application of an extreme control system to operate the reactive power compensator of an electric locomotive

Efficient use of fuel and energy resources is a high-priority area in the energy development strategy of railway transport up to 2030 adopted by OAO Russian Railways. Currently, ac electric locomotives with power rectifier–inverter transformers make up the majority of the usable fleet, in the range of 0.65 to 0.85. This is a cause of not only significant energy losses in the network of traction energy supply, but also restrictions affecting the speed of the locomotive. The energy characteristics of ac electric locomotives can be imptoved via compensation of the reactive power component. The reactive power compensator consists of series-connected capacitor C and inductance L connected to the secondary winding of the transformer. The LC circuit parameters are calculated for reactive power compensation of an electric locomotive in the nominal operation mode. In this article, a reactive power compensation device for electric locomotive made based on a regulated passive compensator was considered. The management of reactive power compensator is carried out by means of extreme control method. It is shown that the extreme control method for a reactive power compensator does not provide for direct calculation of the reactive power of an electric locomotive and significantly simplifies the management structure of a reactive power compensator.     

Emergency operation processes in the thyristor rectifier of an alernating current electric locomotive

In an electric locomotive, the failure of any element or unit of the control system does not have to cause damage to power circuits or emergency operation. A control strategy for a four-zone ac–dc power converter with a discharge diode branch, which is connected in parallel to the rectified current circuit, is proposed. Such control improves the switching conditions of thyristors and allows reduction in the switching time and a decrease in the equivalent inductive reactance of the ac circuit; in addition, it provides reservation due to simultaneous switching of paralleled thyristor branches and skipping of control pulses in any control zone.     

基于分子动理论算法的三电平逆变器谐波优化

在许多大功率交流传动场合下,开关损耗大。为了降低开关损耗,提高逆变器效率,开关频率一般限制在1 kHz以下,导致牵引逆变器中含有大量的谐波。以应用于大功率电力机车的三电平逆变器为特定的研究对象,建立了三电平逆变器最小相电流总谐波畸变率谐波优化模型。采用分子动理论优化算法求解模型时施加了消除窄脉冲算法,完成全调制范围、多种脉波条件下优化函数的求解。与传统SPWM和SHEPWM比较,MMTPWM具有良好的谐波优化效果。最后,通过仿真实验和硬件实验结果验证了理论分析的正确性。     

不同位置再生制动能量吸收装置下直流牵引网潮流计算对比分析

城市轨道交通列车运行时广泛采用再生制动方式,再生制动能量回馈至接触网后被附近运行列车吸收,剩余再生制动能量通过再生制动能量吸收装置吸收以限制接触网压过高。目前,再生制动能量吸收装置安装位置主要有列车安装和变电所安装,不同安装位置下,列车再生制动能量引起对直流牵引供电系统的影响不同。分别建立两种再生制动类型下直流牵引供电系统潮流计算模型,仿真分析了多列车多变电所并列运行下,不同位置再生制动能量吸收装置对牵引供电系统电压、电流及再生制动功率分配的影响。     

基于双模控制的永磁直流电机驱动系统的研究

根据混合动力的工作模式,针对电机电动和回馈制动两种运行状态,提出了双模PWM电流控制策略,在电动运行时,采用PI调节和受限单极PWM控制;在制动过程中,根据通常的PWM控制不能对回馈电流峰值进行有效的控制而可能损坏电池,提出采用电流滞环控制,仿真表明,该控制效果要优于PWM控制回馈制动。以数字信号处理器(DSP)为核心,采用智能功率模块设计了永磁直流电机PWM驱动系统。并对混合动力电动汽车(HybridElectricVehicle,简称HEV)进行了静态和运行实验,实验结果表明本文采用的方法和研制的驱动系统的有效性。     

基于Z源变换器的电动汽车超级电容-电池混合储能系统

Z源变换器具有单级升压、降压、无死区、电压畸变小、可靠性高等优点,在电动汽车领域具有广阔的前景。提出一种基于Z源变换器的电动汽车超级电容-电池混合储能系统。该结构将储能与驱动系统相融合,减少了电池功率变换器,降低了损耗与成本。详细分析通过Z源变换器实现混合储能系统不同模式下功率分配的运行机理。此基础上提出功率分频协调控制策略以提高混合储能系统的响应速度并实现各模式的无缝切换。最后,为了避免短时尺度冲击电流对电池的影响,设计电池瞬态峰值电流估计方法。仿真与实验结果验证了所提出的混合储能系统及控制策略的有效性。     

An efficient braking method for controlled AC drives with a dioderectifier front end

Standard pulsewidth-modulated inverter-fed induction motor drives employ a diode rectifier bridge to supply AC power from the utility to the DC link. Although a diode rectifier is the most cost-effective solution, it does not permit reversing the power flow. This prohibits operating the machine in the regenerative braking mode for active deceleration. An innovative control method substitutes conventional hardware, such as an active front-end rectifier or a chopper controlled braking resistor in the DC-link circuit, by additional software that is implemented in the standard microprocessor control. The control algorithm maximizes the power losses in the machine and in the inverter. It enables regenerative braking operation of the induction motor at high torque. The algorithm conserves the high dynamic performance of a vector-controlled drive system     

能馈型高压变频器整流部分的研究

传统的级联型高压变频器只能电动运行,是电网污染的主要来源之一,为克服此不足,这里提出了一种应用三相PWM整流技术的级联型高压变频器.该变频器采用双闭环控制策略,具有输出电压恒定、单位功率因数运行等特点,可实现电能回馈电网,解决了电网的污染问题.通过实际应用显示,该变频器在降低谐波,抑制直流侧电容两端电压波动等方面有很大...     

HXD1型机车变流器中的直流支撑电容

HXD1型交流机车直流中间回路起着衔接整流和逆变两个环节的作用,其支撑电容不但能稳压、滤波,还能给交流电机负载提供无功功率。本文简单介绍了HXD1型变流器中直流支撑电容的作用、容量的取值、联接方式及放电检测方法。为更深入地研究牵引变流器中的直流支撑电容提供一种了解途径。     

Development of an Induction Machine Commutated Thyristor Inverter for Traction Drives

Several designs detailing the construction of brushless cage-rotor induction machines operating at unity or leading power factor at the 35-hp level have recently been published [1]-[3]. The experimental machine combines the torque characteristics of a conventional cage induction machine with the leading power-factor (PF) capability of an overexcited dc field synchronous condenser into one unit using a common cage rotor and a common stator core. The ability of this machine to naturally commutate a high-power current-source thyristor inverter is apparent without any need for capacitors. The preferred adjustable speed propulsion arrangement consists of a mains-fed phase-delay-rectifier (PDR), high-voltage dc link, and a current-source inverter powering a ten-pole traction motor with constant V/Hz control. The drive system provides continuously variable torque during motoring, and regenerative braking modes and specific details are given for a 150-hp cage-rotor traction motor and converter, capable of natural commutation up to 200 Hz, currently under development.