BPA-PSS/E的数据转换研究及验证

开发基于 VC＋＋语言平台 BPA-PSS/E的数据转换软件,成功将 BPA 数据格式转为 PSS/E格式,并将两者的潮流及暂态稳定结果进行比较.IEEE/９节点仿真系统和某实际电网的仿真结果表明,BPA 和 PSS/E的仿真结果接近,可用 BPA 和 PSS/E软件对电力系统进行仿真.通过转换得到的数据,可用 PSS/E软件方便地实现 BPA 未提供的分析计算功能,可充分利用 PSS/E提供的交互式计算过程控制、自定义模型和控制对电力系统进行深入研究。     

BPA-PSS/E的数据转换研究及验证

开发基于VC++语言平台BPA-PSS/E的数据转换软件,成功将BPA数据格式转为PSS/E格式,并将两者的潮流及暂态稳定结果进行比较。IEEE/9节点仿真系统和某实际电网的仿真结果表明,BPA和PSS/E的仿真结果接近,可用BPA和PSS/E软件对电力系统进行仿真。通过转换得到的数据,可用PSS/E软件方便地实现BPA未提供的分析计算功能,可充分利用PSS/E提供的交互式计算过程控制、自定义模型和控制对电力系统进行深入研究。     

交直流电力系统BPA与PSS/E潮流数据转换分析

通过对BPA和PSS/E两种仿真软件数学模型分析得出两者在潮流数据上的转换关系,编写数据格式转换程序。利用纯交流数据和交直流数据进行仿真计算,以测试数据转换的准确性以及数据转换在交流系统和交直流互联系统上的差异,重点对BPA和PSS/E在交直流互联系统潮流计算结果上的差异进行了原因分析。对两个软件在潮流数据转换中需要注意的问题进行了总结。     

基于中间数据库的PSS/E与BPA数据转换的研究

针对现有电力系统仿真软件PSS/E与BPA间存在的数据异构,不利于软件间数据共享和对比分析计算的问题,分析了基于中间数据库的异构数据源的转换方法,给出模式转换和数据转换实现过程;根据此方法将潮流数据和动态数据从源数据库中读出,通过PowerWorld中间数据库写入目的数据库,完成PSS/E与BPA异构数据的转换。以标准IEEE9节点系统为例进行数据转换和仿真对比分析,仿真结果显示PSS/E和BPA的潮流计算和暂态稳定性计算结果基本相同,证明数据转换是正确的。可见,基于该方法实现PSS/E与BPA的数据转换是可行的。     

PSS/E的直流模型及与BPA直流系统响应特性的比较

阐述了直流系统换相失败和功率恢复特性,并在PSS/E中建立用于电力系统机电暂态过程仿真的直流输电准稳态模型,模拟交流系统故障后直流系统的响应特性。分别用PSS/E和BPA程序对广东电网某年规划方式数据进行了仿真计算,以500 kV北郊—罗洞线路N-1故障为例,分析PSS/E与BPA中直流系统换相失败及后续功率恢复特性的不同。计算结果表明,对于远方系统故障,两个程序的计算结果比较接近,而PSS/E在模拟近处交流系统故障后直流系统的响应特性方面更符合实际情况。     

BPA与PSS/E的暂稳态模型比较和数据转换

为实现将BPA数据格式转化为PSS/E数据格式,在对BPA和PSS/E两种仿真软件暂稳态数学模型分析比较的基础上,编写相应的数据转换接口程序.分别用3机9节点算例和某交直流互联系统的等值系统进行仿真计算,以测试数据转换的正确性.同时对用两个软件计算得出的交流系统和交直流互联系统的潮流计算结果以及纯交流系统的暂态稳定计算结果进行比较,显示两个软件的计算结果比较接近,并对产生差异的原因进行了解释.     

PSS/E在四川电网的应用研究

电力系统仿真软件PSS／E是国际通用的先进仿真软件。引进、消化、吸收和推广使用PSS／E对提升四川电网安全稳定分析水平具有重要意义。开发BPA到PSS／E格式数据转换软件是获得数据的便捷途径,仿真校验可确保所转换模型的有效性和数据的正确性。     

BPA向PSS/E的数据转换及暂态稳定比较研究

BPA和PSS/E均为机电暂态仿真软件,两者潮流数据和暂态模型具有较好的相似性,在对BPA和PSS/E两种仿真软件的暂稳态数学模型分析和比较的基础上,提出了BPA向PSS/E数据转换的详细方法,并通过某交直流系统进行仿真测试,对潮流计算结果和稳定计算结果进行了对比分析,仿真结果表明两者潮流基本一致,暂态仿真结果相似,暂稳态过程基本吻合,表明BPA数据可以准确的转换为PSS/E数据,实现数据共享.     

基于ODM的BPA与PSS/E两端直流潮流数据转换

针对BPA与PSS/E在两端直流线路模型的转换仍不成功的现状,先重点对比分析BPA和PSS/E的两端直流线路模型数据、控制方式和计算公式,并提出通过并联导纳支路进行无功修正的方法消除换流站无功损耗的差异,然后基于开放数据模型（open data model,ODM）编写数据转换程序。最后,通过2DC9节点算例及某实际区域电网测试验证基于ODM的BPA与PSS/E两端直流线路模型数据转换的正确性。     

发电机励磁系统在不同软件中模型转换的研究

随着电网规模的不断扩大和电压等级的不断提高,对机组运行稳定性的要求也随之提高.更为精确详细的励磁系统模型有助于稳定分析.根据时域分段线性法(PLPF法)编写模型转换程序.对PSASP软件中根据实际励磁系统建立的自定义模型应用模型转换程序,得到PSASP、BPA和PSS/E 3种软件下的标准模型参数.通过暂态仿真验证其结果的有效性,并在江苏电网得到应用.     

Development of a network-based power quality diagnosis system

This paper presents a network-based power quality (PQ) diagnosis system. In accordance with the IT development, PQ monitoring networks are prevalent in many existing systems because such networks can provide system-wide insights to users. The developed PQ management system of this paper also consists of network-based devices such as PQ monitoring systems (PQMS), the PQ Server, and the PQ diagnosis system (PQDS). PQMSs measure power quality data at various points in the power systems and send them to the PQ Server through the Ethernet. The PQDS diagnoses the PQ data stored in the PQ Server in order to provide various diagnosis functions to the users. However, in many existing PQ monitoring networks, it is still difficult to pin-point the event location and to find appropriate solutions. The developed PQDS focuses on identifying power quality events, especially on finding the fault location and the type of faults as well as various statistical and stochastic analyses. Therefore, it can help users cope well with power quality problems with the right measure in the right place. The PQ diagnosis system also provides event trend diagnosis, stochastic diagnosis, and PQ indexing functions for user convenience.     

Design and modeling of SMES based SAPF for pulsed power load demands

In this article, a Superconducting Magnetic Energy Storage (SMES) based Shunt Active Power Filter (SAPF) topology is proposed to compensate high power pulsating load demands in a power system. The SMES based SAPF is designed and modeled to realize as an efficient compensator for the compensation of pulsed power load demands. The conventional SAPF is efficient to mitigate the power quality problems in a power system unless there is high power pulsating load demands, transient conditions or power fluctuations. Particularly, a Modified Synchronous Reference Frame (MSRF) control algorithm has been implemented to generate proper switching signals for the three-phase Voltage Source Converter (VSC) of the SMES based SAPF. In the simulation, it has been seen that the SAPF is incompetent under high power pulsating load demands whereas the SMES based SAPF has shown excellent performance under such load conditions. Moreover, a comparative analysis has been made between the conventional SAPF and the SMES based SAPF under pulsating load conditions, to check the effectiveness of the SMES based SAPF. The performance of the proposed system is presented by using Sim Power System (SPS)/MATLAB Simulink and real-time digital simulator laboratory (RTDS-Lab).     

对光伏的两种输出最大功率点追踪法分析

分析了两种最大功率追踪(MPPT)的方法:扰动观察法(Perturbation and Observation,P&O)与功率反馈法。利用仿真模拟并评估了两种方法的性能,二者功率追踪精确性都可以达到99%以上,但是不同的追踪手段会在追踪时间、系统稳定性、实现成本等方面产生不同的影响。本文旨在仿真结果的基础上,对上述问题进行分析与优化。     

On the inter-area optimal voltage and reactive power control

Scheduling voltage and reactive power is one of the major problems and concerns of the Transmission System Operators (TSOs) especially after deregulation of power market. Due to locally provision of the reactive power resources, each TSO has developed its own specific method. Hence, the voltage and reactive power coordination in the interconnected system has got less attention. In this respect, current practices of different TSOs in Europe and North America, as examples of interconnected power systems, are investigated in this paper. Afterwards, it focuses on the inter-area optimization of the voltage and reactive power. Instead of performing the studies around one particular optimization, different aspects of the mathematical formulation of the optimization problem in the interconnected power system, including objective function, constraints and appropriate modeling of neighboring areas, are revisited more in depth. Various possible implementations of coordinated approaches, including centralized and decentralized structures, as well as non-coordinated approach in collaborative and non-collaborative environments are studied. In this respect, new contributions are proposed in this paper by using the distributed slack bus model and the limitation of the voltage and reactive power in the interconnections links. The comparative analysis between the available and proposed methods are discussed in terms of sub-optimality and time to convergence. The discussions are based on New England 39 bus system and the presented results in the literatures.     

Comprehensive modelling of the unified power flow controller for power system control

In this paper, comprehensive modelling of the unified power flow controller (UPFC) for power flow, voltage, angle and impedance controls is presented. The control modes include some thirteen different power flow, voltage, angle and impedance control functions. The similarities and differences between some of the control modes and those of traditional transformers and series compensation devices are also discussed. The control modes were successfully implemented in a Newton power flow algorithm. Numerical examples are given on the IEEE 30-bus system and the IEEE 118-bus system to illustrate the feasibility and the performance of the Newton power flow algorithm.     

电力线载波通信中的自动增益控制技术

在电力线载波通信系统中,电平的稳定与否直接影响着载波通信系统的传输质量。在恶劣电力线通信环境下,只有努力提高自动增益控制(AGC)水平,才能实现信号电平的稳定。文章介绍了一项针对电力线载波通信数字接收机的自动增益控制技术。在分析研究了各种AGC算法的分类及其应用的基础上,选择其中2种AGC算法,设计出一种模拟和数字相结合的2级AGC控制方案,并通过仿真实验结果证明了该方案的可行性和有效性。     

Stochastic operational scheduling of distributed energy resources in a large scale virtual power plant

Virtual Power Plant (VPP) is introduced as a tool for the integration of distributed generations, energy storages and participation of consumers in demand response programs. In this paper, a probabilistic model using a modified scenario-based decision making method for optimal day ahead scheduling of electrical and thermal energy resources in a VPP is proposed. In the proposed model, energy and reserve is simultaneously scheduled and the presence of energy storage devices and demand response resources are also investigated. Moreover, the market prices, electrical demand and intermittent renewable power generation are considered as uncertain parameters in the model. A modified scenario-based decision making method is developed in order to model the uncertainties in VPP’s scheduling problem. The results demonstrated that the optimal scheduling of VPP’s resources by the proposed method leads VPP to make optimal decisions in the energy/reserve market and to play a dual role as a demand/generation unit from the perspective of the upstream network in some time periods.     

电力线载波通信设备的生产许可证管理

文章介绍关于我国电力线载波通信产品生产许可证管理所涉及的问题,包括我国工业产品生产许可证制度的起源及发展,电力线载波通信设备生产许可证的实施细则,以及相关的政策、申证范围、申请手续、办证程序、企业实地生产条件核查、产品抽样、质量检验、委托加工备案以及所相关的其他问题,重点指出了企业必须具备的生产条件、现场核查的判据和质量检验所依据的标准。对我国电力线载波通信设备生产企业如何遵循国家强制性法规和建立良好的生产条件和管理体系具有实用化的指导意义。     

农村10 kV配电线路高频信道特性测试及分析

利用中压电力线实现高速数据通信,目前在国内尚属一项空白。如果能够充分运用农村高覆盖率的中压配电网,进行远距离PLC高速通信,将推进农村信息化建设和开创电力工业新的经济增长点。文章对中压(10 kV)配电线路的高频信道特性进行了测试研究,并以河北省某乡一座35 kV变电站的10 kV出线为测试对象,自行搭建测试系统,进行了噪声特性、衰减特性、阻抗特性方面的测试,掌握了相应数据资料。笔者通过分析,提出了选用2~12 MHz作为实现中压PLC远距离高速数据传输工作频段的建议。     

Management of reactive power sharing & power quality improvement with SRF-PAC based UPQC under unbalanced source voltage condition

This paper is proposed to establish a new control algorithm for UPQC (unified power quality conditioner) to improve power quality and manage effectively equal reactive power sharing between shunt and series inverter of UPQC under unbalanced source voltage condition. The extraction of instantaneous power angle for reactive power sharing faces difficulty with unbalanced source voltage condition. This paper presents a new SRF (synchronous reference frame) based PAC (power angle control) method using decoupled load current parameters for efficient utilization and coordination of UPQC inverters. The proposed controller contributes in improvement of source current and load voltage harmonic profile, provides efficient way of load reactive power compensation and load voltage compensation for sag, swell and unbalanced condition. Effect of source voltage variations in the form of sag, swell or unbalancing on variable power angle estimation and reactive power calculations are also validated through a mathematical analysis. SRF based PAC control approach and PAC based UVT (unit vector template) control approach is adapted for estimating the reference signals of shunt and series inverter respectively and thus reducing the need of extra computation. The simulation and experimental analysis is carried out using Matlab/Simulink software package for computer simulation and a dSPACE based experimental setup for real time verifications.