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Stability Enhancement and Blackout Prevention by VSC Based hvdc

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Journal of Energy and Power Engineering 2012年第11期6卷 1891-1900页

作者： Ying Jiang-Hafner Rolf Palsson Malin Agren Thomas Nordlander Pehr Hjalmarsson ManfredManchen ABB Power Systems HVDC Ludvika 77180 Sweden Power System Planning Department Nambian Power Utility Windhoek 2864 Nambian

This paper deals with the operation and performance of VSC （voltage source converter） based hvdc （high voltage direct current） interconnecting two extremely weak AC networks, the experience of Caprivilink project. It is shown in the paper that the hvdc converter automatically provides the supreme voltage and frequency stabilizing function when a critical situation is detected, no matter the disturbances appeared in sending end or receiving end AC networks. This supreme voltage and frequency stabilizing function makes it possible to avoid the blackout even if all the generators are tripped under an extra-ordinary worst contingency. By plots of recorded transients, the paper will show how the eventual blackouts are avoided.

关键词： hvdc VSC transmission system blackout weak AC system stability.

Influence of Qinghai-Tibet hvdc Transmission System on AC Transmission Line Protections in Qinghai Power System

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Electricity 2014年第4期25卷 26-33页

作者： Li Hongzhi Wu Yonggang Wang Ningxia Cheng Jing Zhang Hongping Qinghai Electric Power Corporation

To analyze the influence of _＋400 kV Q^nghai-Tibet hvdc transmission system on transmission- line protections in Qjnghai AG power system, a closed-loop simulation system was constructed by combing HyperSim system with HVDG control protection devices. Various faults on double-circuit 750 kV and multi- circuit 330 kV AC transmission lines in Qjnghai power system were simulated. The impedance characteristics and harmonic components at Qjnghai side of Qjng-Tibet DG transmission line were analyzed. The harmonic proportion in voltages and currents were studied for faults that took place at different locations near the DG system. The inflence of Qing-Tibet DG system on the directional components of protections, differential protections and distance protections of AC transmission lines was discussed and drew the conclusions that the DC sytem had little influence on differential protections, while had great inflence on directional components and distance protection. The conclusions can provide reference for studying the interaction between AC and DG systems.

关键词： hvdc closed-loop test transmission-line protection harmonic component

Comparative Simulation Study between Gate Firing Units for hvdc Rectifier Based on CIGRE Benchmark Model

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Energy and Power Engineering 2011年第2期3卷 120-134页

作者： Bhaba Priyo Das Neville Watson Yonghe Liu 不详

A simulation study between the DQO gate firing unit (GFU) and a proposed GFU for high voltage direct current (hvdc) rectifier based on the CIGRE benchmark model in Matlab/Simulink is carried out. The proposed GFU does not use traditional phase lock loop (PLL) and offers structural simplicity, fast response and immunity to ac system voltage unbalance, harmonics, voltage sag, frequency jump and phase jump etc. Since there is no loop filter, no tuning issues are involved. Advantages of the proposed GFU are confirmed by extensive simulation results.

关键词： CIGRE hvdc Phase Lock Loop Rotating reference Frame Simulation

Simulation on DC Current Distribution in AC Power Grid under hvdc Ground-Return-Mode

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Journal of Electromagnetic Analysis and Applications 2010年第7期2卷 418-423页

作者： Guihua Mei Yuanzhang Sun Yancun Liu 不详

This paper focus on the Modeling and Calculation of DC current distribution in AC power grid induced under hvdc Ground-Return-Mode. Applying complex image method and boundary element method, a new field-circuit coupling model was set up. Based on the calculation result with complex image method, this paper derived the modification factor for induced earth potential from practical measurement, which increased the accuracy of calculation. The modification method is helpful for evaluation on the effect of means used for blocking the dc-bias current in transformer neutral and also useful for the forecast of the DC current distribution when the power grid is in different line connection mode. The DC distribution character in Guangdong power grid is shown and suggestion is proposed that the mitigation of dc-bias should start from those substations whose earth-potential is highest.

关键词： hvdc DC-Bias DC Distribution Ground-Return Current Simulation

Performance of PSS to Damp Power Oscillations Caused by an hvdc Link in AC-DC Power System

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Energy and Power Engineering 2014年第1期6卷 1-9页

作者： Mokhtar Benasla Tayeb Allaoui Mostefa Brahami Department of Electrical Engineering ICEPS Laboratory Djillali Liabes University Sidi Bel Abbes Algeria Department of Electrical Engineering L2GEGI Laboratory Ibn Khaldoun University Tiaret Algeria

hvdc (High Voltage Direct Current) systems are increasingly being applied to improve power system operation and controllability. However, inappropriate setting of hvdc controller may have a detriment effect on the system performance. Generally, PSS (Power System Stabilizer) is known as a simple concept, easy to perform, and computationally effective to enhance damping of power system oscillations through excitation control of synchronous generator. This paper examines the effectiveness of the PSS to enhance the dynamic performance of AC-DC power systems and to compensate the negative damping of hvdc system. The dynamic performance is evaluated by examining the system response to various disturbances. In order to ensure the reliability of the simulation test results as well as the performance of the PSS, detailed hvdc modeling is adopted using SimPowerSystems toolbox in the MATLAB, and some important conclusions are drawn.

关键词： hvdc PSS AC-DC Power Systems Power System Stability

Advanced Analysis of hvdc Electrodes Interference on Neighboring Pipelines

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Journal of Power and Energy Engineering 2015年第4期3卷 332-341页

作者： Yu Gong Chunlin Xue Zhilei Yuan Yexu Li Farid Paul Dawalibi China Southern Power Grid Guangzhou China Huadong Power Design Institute Shanghai China Safe Engineering Services & Technologies ltd. Laval Quebec Canada

This paper focuses on advanced analysis techniques and design considerations of DC interference generated by hvdc electrodes during normal bipolar and temporary monopolar operations on neighboring metallic utilities, with a special emphasis on buried gas and oil pipelines. This study examines the level of pipeline corrosion, the safety status in the vicinity of exposed appurtenances and the impact of DC interference on the integrity of insulating flanges and impressed current cathodic protection (ICCP) systems. Computation results obtained for different soil models show that different soils can lead to completely different DC interference effects. The results and conclusions presented here can be used as a reference to analyze the severity of DC interference on pipelines due to proximate hvdc electrodes.

关键词： hvdc Electrode DC Interference Pipe-to-Soil Potential Polarization Potential Insulating Joint (Flanges) Rectifier Touch Voltage Corrosion Safety Impressed Current Cathodic Protection

Stability Enhancement in hvdc System with STATCOM

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Engineering（科研） 2011年第11期3卷 1072-1081页

作者： Sung-Doo Lee Chan-Ki Kim Jin-Young Kim Eung-Bo Sim 不详

This paper deals with the stability problem at the inverter end of a hvdc link with STATCOM (Static Compensator), when connected to a weak AC system which has the stability enhancement for power instability and commutation failures. The hvdc stability problem is tackled with a STATCOM which not only provides a rapid recovery from power, harmonic stability and commutation failures but also offers a lower cost filter design for the hvdc system. PSCAD/EMTDC simulations are presented to demonstrate the robust performance and to validate the proposed topology.

关键词： hvdc Transmission STATCOM

New Concept for Calculating DC Harmonic Voltages and Currents in BTB hvdc Converters

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Journal of Power and Energy Engineering 2014年第11期2卷 33-42页

作者： Chan-Ki Kim Seong-Doo Lee Soon-Ho Choi Yong-Beum Yoon KEPCO KEPRI (Korea Electric Power Research Institute) Daejeon Korea

This paper deals with a new concept for calculating DC harmonic voltages and currents of line- commutated hvdc systems. In contrast to the conventional method, this method is useful for BTB (Back-To-Back) hvdc systems without smoothing reactors or PTP (Point-To-Point) with very short transmission line. This method proposes a new direction for hvdc system design and analysis. The proposed method is applied to a 50 Hz/60 Hz BTB test system and a synchronized BTB test system. After simulation and verification, the new results are introduced.

关键词： hvdc BTB (Back-To-Back) PTP (Point-To-Point)

Design of the Optimal Self-tuning Fuzzy-Pi Controller for Rectifier Current Control in hvdc System

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Design of the Optimal Self-tuning Fuzzy-Pi Controller for Re...