燃机电厂黑启动与保安柴油发电机组配置方案及启动方式研究

[目的]为了降低燃机电厂初期投资,在保证机组安全的同时,通过黑启动功能获取广东辅助服务经济补贴,提出了扩建燃机时采用多台柴油发电机组的配置方案,用于9F机组事故停机保安电源,同时又作为原9E机组黑启动电源。[方法]为了实现技术经济最优化,通过柴油发电机组配置及厂用电接线的多方案比选论证,给出了合理配置方案。并对推荐方案的事故停机控制逻辑以及黑启动控制逻辑进行论述。[结果]通过黑启动试验结果表明,各电气量均满足规范要求,推荐方案能满足黑启动功能并通过电网公司验证。[结论]多台柴油机同时用于黑启动及保安功能的方案,为今后燃机电厂黑启动及保安电源工程设计提供参考及借鉴。     

保安段供电可靠性方案与实施

某公司原保安段有两路电源供电,工作电源由机组380 VPC段提供,故障时通过ATS开关控制连锁起动柴油发电机给保安段供电,由于保安段至柴油发电机控制回路平时不能进行试验,出现故障时,柴油发电机不能启动,一旦工作电源失去,易造成保安段失电。通过对保安段供电电源改造,实现三路电源供电,故障时自动切换至备用电源,正常运行时定期并列切换,保证在保安段不停电的情况下检测备用设备及回路正常。通过改造,提高了保安段供电可靠性,保证主机设备运行安全。     

基于顺控的火电厂保安电源控制逻辑的设计

快速柴油发电机组在火电厂保安电源系统中有着广泛的应用,基于PLC,运用顺序控制设计方法对保安电源控制系统进行模块化程序设计,提高设计效率,缩短调试时间,也使电气控制系统的可靠性增强。     

陇东能源基地电源及电网建设方案研究

介绍了陇东能源基地煤炭、水资源情况,以及陇东地区电源建设规划,分析了陇东本地电网建设方案、陇东直流换流站及配套外送电源接人系统方案。重点论证了直流网侧交流电压、换流站站址、配套外送电源接人系统电压方案、站与地区电网的衔接等主要问题,提出直流网侧电压750kV方案和330kV方案各有优势,而配套外送电源建议主要考虑以直流网侧交流电压直接接人换流站。可为今后陇东地区电源电网建设及直流工程开展进一步工作提供参考。     

高精度加速器超导磁铁电源的研究

针对超导磁铁对电源的要求,提出了基于Buck Chopper电路的多相多重化的电源拓扑结构,采用IGBT为卸能开关来实现失超快速保护,分析了其工作原理.按该方案研制了一套高精度加速器超导磁铁电源,进行了严格的测试,结果表明,该方案满足了同步加速器超导磁铁对电源的高要求.     

提高某大型医疗建筑工业柴油发电机可靠性措施探讨

为解决某大型医疗建筑备用电源柴油发电机一次启动成功率低的问题,对柴油发电机组控制器盘车时间、怠速延时参数进行了优化,完善柴油发动机怠速控制回路,提高柴油发电机组可靠性,保证保安电源失电后在30s内可由柴油发电机恢复供电.     

基于遗传算法的分布式电源综合效用优化问题研究

鉴于分布式电源的接入会对电力系统运行产生重要影响及优化电力系统中分布式电源的位置和容量对发挥分布式电源的技术和经济效用具有重大意义,通过对比分布式电源引入前后系统属性的变化比率确定了相应的指标体系,建立了包含各指标在内的综合效用目标函数,应用遗传算法对多目标问题进行优化,确定了综合效用最优时分布式电源的位置和容量,并通过算例进行了验证分析。结果表明,采用遗传算法能获得位置和容量较合理的分布式电源优化方案,同时获得了最优方案对各指标的影响程度。     

层次分析法在资源综合利用电源规划中的应用

针对宁夏电网分层分区特点,提出了一套资源综合利用机组及电源点布局合理性的综合评价指标体系,应用电源规划软件PowerPlan获得了四个可比且较优的电源规划方案,采用层次分析法对该方案进行综合评价获得了较优方案,为结构优化提供了较全面完整的指标和新途径。     

抽水蓄能电站保安电源配置分析

抽水蓄能电站能为电网提供优质的大容量清洁电力储备,很好地满足了电网安全稳定经济运行需求,更是吸纳新型绿色能源稳定入网的关键保障。为了使抽蓄电站更好地服务电网,本文介绍了我国在运、在建抽蓄电站典型枢纽结构,重点介绍了抽蓄电站保安电源配置及负荷分配原则,统计分析了现行抽蓄电站事故保安电源配置情况和主要影响因素,明确了保安负荷确定原则以及保安容量的计算方法。研究不仅为从事抽蓄建设管理的人员提供技术指导和帮助,也为我国抽蓄电站未来的设计规划提供重要的参考和依据。     

天津电力通信UPS改造方案设计与实现

随着通信设备数量的不断增加以及对电源可靠性要求的不断提高,天津电力本部通信机房原不间断电源系统(Uninterruptible Power System,UPS)已无法满足运行要求。通过对原UPS运行方式的分析和对交流通信设备负载的计算,设计了UPS改造方案,并利用此方案完成了天津电力本部通信机房UPS的改造工作。改造后UPS系统的容量、可靠性等均较改造前有显著提升,同时确保了交流通信设备的供电安全,可以为今后电力通信机房UPS的设计、改造和实施提供参考和借鉴。     

Advanced concept for dispersed power supply system using AC modules

A method of for estimating the reliability of new conceptual stand-alone dispersed power supply systems using AC modules with self-contained logic was proposed and system reliability estimated using a yearly scale simulation. The AC module is able to supply AC power on each module and has the flexibility to enable construction of a grid-connected system. Power storage devices were required when applying AC modules to the stand-alone power supply system. For these power storage devices, we used a battery with a built-in DC/AC micro bi-directional inverter known as AC battery. To maintain the flexibility of the system extension, the AC modules and AC batteries were controlled by self-contained logic. This logic performs parallel operations for the voltage control inverter and keeps supply and demand in balance.     

电气化铁路供电系统电能质量补偿器的混合补偿方法研究

为了提高牵引供电系统的电能质量（PQ）,降低补偿器的额定功率和运行成本,提出了一种静态无功补偿器集成的铁路电力调节器（RPC）。 RPC是交流电气化铁路系统中广泛使用的设备,用于增强主网络的PQ指数。该设备的下一代产品是有功电能质量补偿器（APQC）。本文提出了一种混合技术来解决上述问题。将SVC作为辅助设备与主补偿器...     

A microcontroller-based stand-alone photovoltaic power system for residential appliances

In this study, a stand-alone photovoltaic power system was designed and implemented to operate residential ac-powered appliances such as fluorescent lambs, fans etc. Sun-tracker is implemented for improved efficiency of the system by keeping the solar module perpendicular to the sun's incoming rays. The charge method is realized with closed-loop current control of buck-boost dc–dc converter. The proposed system also uses a voltage source type PWM inverter to convert DC voltage from battery storage to supply AC loads. In the PWM method used, selected harmonics are eliminated with the smallest number of switching and an improvement in the system efficiency by reducing switching losses and providing ease of filtering on the inverter output is obtained. Charge controller and PWM inverter systems have been realized by using PIC16F873 microcontrollers. An experimental system was implemented to demonstrate the effectiveness of the proposed system. Simulation and experimental results are given to verify the system's efficiency.     

PWM整流器在变速恒频风力发电系统中的应用

变速恒频风力发电系统要求励磁电源有良好的输入、输出特性和能量双向流动的能力.交-直-交双PWM变频器是理想的励磁电源,而PWM整流器是其中一项关键技术.文章从三相电压型PWM整流器主电路拓扑结构出发,建立了基于三相静止坐标系和两相同步旋转坐标系的数学模型.阐述了电压、电流双闭环控制的基本原理和空间矢量脉宽调制技术在三相PWM整流器中的应用.在Matlab/Simulink环境下,对其进行了单位功率因数整流和逆变的仿真研究.结果证明,该整流器是满足交流励磁需要的理想整流电源.     

光伏水泵提水系统功率补偿控制策略研究

分析系统等效模型,提出一种采用市电补偿的供电方案和基于直流母线电压的功率补偿控制策略,通过检测直流母线电压判断光伏阵列出力与负载功率之间的关系,为系统不同供电模式的切换提供依据,保证系统供电功率的稳定。经仿真和实验验证控制策略的有效性。     

AC/DC power conversion interface for self-excited induction generator

A new AC/DC power conversion interface for the self-excited induction generator (SEIG) is proposed here. The proposed AC/DC conversion interface includes an excitation systemand a diode rectifier connected in parallel.The variable frequency AC power generated by the SEIG is converted into DC power by the diode rectifier.The DC power of the diode rectifier can charge a battery set and supply DC loads or be further converted into fixed-frequency AC power by an inverter for AC loads.The DC voltage is expected to be regulated in the above applications.The excitation system supplies an exciting reactive current to maintain the amplitude of the SEIG output voltage to be a constant value. Moreover, it can also serve as an active power filter to suppress the harmonic current generated by the diode rectifier. The excitation system is composed of an AC power capacitor and a power converter connected in series. The AC power capacitor is adapted to provide a basic reactive power, and it can also reduce the voltage rating and the capacity of the power converter. The salient point of the proposed AC/DC power conversion interface is that the capacity of the power converter in the AC/DC power conversion interface can be minimised, and the power loss of the AC/DC power conversion interface can also be reduced. A prototype is developed and tested to verify the performance of the proposed AC/DC power conversion interface.     

一种新型移相PWM软开关感应加热电源的研究

介绍了一种新型移相调功高频感应加热电源：逆变电路可以在大的调功范围实现软开关,且只需要一个吸收电容：通过实验对比IGBT模块的关断损耗,证实吸收电容能有效地提高电源的转换效率。转换效率达到了96．4％。     

Stored energy control for long-term continuous operation of an electric and hydrogen hybrid energy storage system for emergency power supply and solar power fluctuation compensation

In order to realize a large-capacity stand-alone emergency power supply that enables highly reliable and high-quality power supply at the time of a large-scale natural disaster and enables effective use of solar power generation, we proposed an electric and hydrogen hybrid energy storage system (HESS). It is composed of an electric double-layer capacitor bank, fuel cell, electrolyzer, and hydrogen storage (buffer gas tank and metal hydride). In an emergency, this HESS is expected to supply power for loads together with photovoltaics panels for a long time. In usual time, it should not only cooperate with external electricity grids to convert unstable photovoltaic output power into reliable power supply, but also maintain sufficient stored energy in case of emergency. To realize the continuous operation of the HESS in both emergency and usual time, we proposed an electric double-layer capacitor's state-of-charge feedback control method and a hydrogen energy feedback control method, coordinating an energy management method based on Kalman filter algorithm. An experiment and a simulation demonstrated the operations of a 10-kW scale model HESS in emergency and usual time mode, respectively. The demonstrations verified the correct performance of the proposed HESS with the proposed control methods and enabled the continuous operation of the HESS.     

An integrated simulation model for PEM fuel cell power systems with a buck DC-DC converter

Fuel cell powered systems generally have a high current and a low voltage. Therefore, the output voltage of the fuel cell must be stepped-down using a DC-DC buck converter. However, since the fuel cell and converter have different dynamics, they must be suitably coordinated in order to satisfy the demanded load. Accordingly, this study commences by constructing a MATLAB/Simulink model of a proton exchange membrane fuel cell (PEMFC) system comprising a PEMFC stack, an air/fuel supply system, and a temperature control system. The validity of the PEMFC model is demonstrated by comparing the simulation results obtained for the polarzation curves of a single fuel cell with the corresponding experimental curves. A model is then constructed of the DC-DC buck converter used to step-down the PEMFC output voltage. In addition, a sliding mode control (SMC) scheme is proposed for the DC-DC buck converter which guarantees a low and stable output voltage given transient variations in the output voltage of the PEMFC. Finally, a model is constructed of a DC-AC inverter with a pulse width modulated (PWM) control scheme which enables the PEMFC stack to supply the grid or power AC applications directly. Overall, the combined PEMFC/DC-DC buck converter/DC-AC inverter model provides a powerful and versatile tool for the design and development of a wide range of PEMFC power systems.