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基于单级多电平开关变流的超大容量海上风电变流器

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电力自动化设备 2024年第8期44卷 45-53,61页

作者：宋强王云飞赵彪余占清刘文华曾嵘清华大学电机工程与应用电子技术系北京100084

海上风机正向超大容量方向发展,基于较低电平数目变流技术的风电变流器在电压、容量等级的提升方面受到限制。提出了基于单级多电平开关变流的超大容量海上风电变流器方案,采用直流电压可大范围调节的宽直流电压模块化多电平变流器(MMC)... 详细信息

海上风机正向超大容量方向发展,基于较低电平数目变流技术的风电变流器在电压、容量等级的提升方面受到限制。提出了基于单级多电平开关变流的超大容量海上风电变流器方案,采用直流电压可大范围调节的宽直流电压模块化多电平变流器(MMC),在单级多电平变流器中实现DC/DC和DC/AC两级变换功能。基于风电变流器的单向功率传输特性,采用单向电流型宽直流电压MMC优化开关器件用量,并基于负电平利用优化调制比大幅降低MMC的子模块电容用量。所提出的方案不仅具有电压与容量等级高、功率损耗低、谐波含量低的优势,还能最大限度降低开关器件和电容的用量。与现有风电变流器方案进行对比,结果表明所提方案在经济性、运行性能等方面具有显著优势。通过仿真验证了所提方案拓扑结构和控制策略的可行性和有效性。

关键词：海上风电变流器模块化多电平变流器变流器拓扑宽直流电压超大容量

新型IGCT直流输电换流阀运行试验研究及其等效性评估

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中国电机工程学报 2024年第10期44卷 4112-4122,I0031页

作者：王宗泽余占清许超群陈政宇屈鲁赵彪曾嵘清华大学电机工程与应用电子技术系北京市海淀区100084 国家电网有限公司北京市西城区100031

换相失败问题(commutation failure,CF)是电网换相换流高压直流输电技术(line commutated converter high voltage directcurrent,LCC-HVDC)面临的固有难题。为了解决该问题,已有文献主要从拓扑结构、控制策略等方面着手,鲜见抵御换相... 详细信息

换相失败问题(commutation failure,CF)是电网换相换流高压直流输电技术(line commutated converter high voltage directcurrent,LCC-HVDC)面临的固有难题。为了解决该问题,已有文献主要从拓扑结构、控制策略等方面着手,鲜见抵御换相失败的新型换流阀研制及试验研究。该文开展基于大功率逆阻型集成门极换流晶闸管(reverse blocking integrated gate commutated thyristor,RB-IGCT)的新型换流阀试验研究及试验等效性分析。首先,阐释新型换流阀抵御换相失败的原理,并针对新型换流阀不同的工作模式,提出对新型电力电子器件的需求。然后,利用现有的型式试验合成回路平台开展适用于传统晶闸管换流阀的运行试验,并分析试验结果,得出大部分试验项目等效性较好而小熄弧角试验和关断试验等效性较差的结论。最后,针对这两项特殊试验提出新的试验方法和试验电路,可为新型换流阀的研发和应用提供一定的技术基础。

关键词：新型换流阀电网换相换流器合成试验回路型式试验换相失败逆阻型集成门极换流晶闸管

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IGCT门阴极换流路径杂散阻抗在线监测方法研究

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电网技术 2024年第5期48卷 2152-2160页

作者：朱鸿凡吴锦鹏王鹏陈政宇刘佳鹏余占清曾嵘清华大学电机工程与应用电子技术系北京市海淀区100084

集成门极换流晶闸管(integrated gate commutated thyristor,IGCT)换流路径杂散阻抗是评估其关断能力的重要参数,现有离线测量方法有诸多缺陷并且测试过程复杂,实时性差。该文主要针对IGCT换流路径杂散阻抗在线监测问题,结合IGCT关断过... 详细信息

集成门极换流晶闸管(integrated gate commutated thyristor,IGCT)换流路径杂散阻抗是评估其关断能力的重要参数,现有离线测量方法有诸多缺陷并且测试过程复杂,实时性差。该文主要针对IGCT换流路径杂散阻抗在线监测问题,结合IGCT关断过程,分析了换流路径杂散阻抗的构成;根据基尔霍夫电流定律(Kirchhoff’s current law,KCL)、基尔霍夫电压定律(Kirchhoff’s voltage law,KVL)推导了换流路径电压、电流方程,进而提出基于阴极集成印刷电路板(printed circuit board,PCB)式电流传感器的换流路径杂散参数在线监测方法;采用高速采集卡和LabVIEW软件,构建了测量系统;通过在高压、大电流加速老化测试平台上的实际测试,实现了mΩ级电阻与nH级电感的杂散阻抗准确提取,验证了在线监测方法的有效性。

关键词：集成门极换流晶闸管换流路径杂散阻抗在线监测

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Resistance Characteristics of Arc in Long Air Gap

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高电压技术 2013年第8期39卷 1881-1885页

作者： yu zhanqing yu Junjie ZENG Rong CHEN He PENG Xiang State Key Laboratory of Control and Simulation of Power System and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing 100084 China Maintenance and Test Center of EHV Power Transmission Company China Southem Power Grid Co. Ltd. Guangzhou 510663 China

Arc resistance is an important parameter for characterizing long arcs in air, and its laboratory testing is of importance for accurate arc modeling of electromagnetic transient caused by short circuit fault. Therefore, we constructed an experimental system to study the cha- racteristics of long AC arc in air. Driven by currents of 10 kA or 40 kA (root mean square value), the system produces arcs with different initial lengths of 1 m, 2 m and 4 m, and the movement of the arcs are captured by a high-speed camera. After performing experiments using the system, we carried out analysis and comparisons of the arc resistance of arcs with different lengths and different currents, as well as a study of the relationship between the macro-morphology and the resistance of the arcs. Conclusions were drawn from the experimental re- sults: the arc voltage had obvious saturation characteristics; the arc resistance increased with the increase of arc length and the decrease of current; the arcs bended or extended significantly in time and the peak arc voltage within a single cycle increased correspondingly; the arcs had voltage and current in the same phase. In the end, a formula of arc resistance based on the experiment results is derived.

关键词：耐电弧性电阻特性空气间隙实验室测试电流驱动实验系统初始长度电弧电压

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数据中心全直流供电系统的构建及其综合评价

浙江电力 2024年第3期43卷 75-83页

作者：韩雪姣屈鲁王长永崔康生余占清崔健清华大学能源互联网创新研究院北京100085 台达电子集团上海201209 清华四川能源互联网研究院成都610299

“双碳”目标对数据中心提出了高效率、高可靠、低碳排放的需求。因此,构建了一种接入可再生能源和大规模储能的数据中心全直流供电系统,并对其进行了综合评价。首先,分析数据中心供电系统“源-网-荷-储”各环节的特点和需求,综合考虑... 详细信息

“双碳”目标对数据中心提出了高效率、高可靠、低碳排放的需求。因此,构建了一种接入可再生能源和大规模储能的数据中心全直流供电系统,并对其进行了综合评价。首先,分析数据中心供电系统“源-网-荷-储”各环节的特点和需求,综合考虑系统效率、可用性、经济性、环保性4个维度,建立了评价指标体系。然后,利用AHP(层次分析法)和模糊综合评价法,开发了DCES(数据中心能源系统)架构评价工具。最后,通过DCES将全直流供电系统与传统交流供电系统进行对比评价,结果表明,提出的全直流供电系统尽管经济性稍差,但综合评价指标更优,可作为未来数据中心新型供电系统的一个可选方案。

关键词：数据中心供电系统全直流供电综合评价

Effect of Uncertainty of the Pre-Exponential Factor on Kinetic Parameters of Hydrocarbon Generation from Organic Matter and its Geological Applications

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Acta Geologica Sinica(English Edition) 2013年第1期87卷 211-218页

作者： WANG Min LU Shuangfang XUE Haitao yu zhanqing Research Institute of Unconventional Petroleum and Renewable Energy China University of Petroleum

The source rock sample of the Shahejie Formation （upper Es4） in Jiyang Sag was pyrolyzed under open system with the Rock-Eval-lI apparatus, and then kinetic model parameters were calibrated for investigating the effect of uncertainty of pre-exponential factors on kinetic parameters and geological applications, where the parallel first-order reaction rate model with an average pre- exponential factor and discrete distribution activity energies was used. The results indicate that when the pre-exponential factor changes from low to high, an extreme value for residual errors occurs. And with the increasing pre-exponential factor, the distribution shape of activation energies are nearly the same, but the values of activation energies move higher integrally, and the average activation energy increases about 12 kJ/mol for every 10-fold of the pre-exponential factors. Extrapolating the geological heating rate of 3.3 ~C/Ma, the results show that with the increases in pre-exponential factor, the geological temperature corresponding to TRo.5 （transforming ratio of hydrocarbon generation is 50%） increases gradually, and the additional temperature gradually decreases. Combined with geochemical data of source rock, the kinetic parameters with different pre-exponentia[ factors are used to calculate the transformation ratio of hydrocarbon generation, and the result indicates that kinetic parameters corresponding to the better optimized pre-exponential factor are more suitable. It is suggested that the risk assessment of hydrocarbon generation kinetic parameters should be enhanced when using the kinetic method to appraise the oil-gas resources. Meantime, the application result of different kinetic parameters should be verified with geological and geochemical data of source rock in the target area; therefore, the most suitable kinetic parameters for target can be obtained.

关键词： Pre-exponential factor activation energy uncertainty hydrocarbon generation kinetics,geological application

Influence of Meteorological Parameters on Electromagnetic Environment of UHVDC Transmission Line Under High Altitude Condition

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高电压技术 2012年第12期38卷 3177-3181页

作者： LIU Lei LI Min LI Ruihai yu zhanqing LIUZhihong LIU Xiangshi Electric Power Research Institute China Southern Power Grid Co. Ltd. Guangzhou 510080 China Department of Electrical Engineering Tsinghua University Beijing 100084 China Zhumadian Electric Power Company China State Grid Company Zhumadian 463000 China

Measuring the electromagnetic (EM) environment parameters of a transmission line in bad weather conditions (such as rain, wind, etc.) is difficult for technical staff. In the National Engineering Laboratory for UHV Technology (Kunming),a test line was completed for EM environment tests. An automated EM environment testing system was installed under the line, the radio interference (RI),audible noise (AN),resultant electric field strength(E_s),and ion current density (J_s) at ground level were measured under all weather conditions within a voltage range from ± 800 kV to ± 1 000 kV over two years. Based on the measurement results, the influence of meteorological parameters on the EM environment of the transmission line was studied. When the H_R increases from 40% to 80%, the RI, AN, E_s, Js would have different degrees of attenuation. The RI on a rainy day is 3 dB lower than that of a sunny day, while the Js gets a sharp increase with the same weather condition change. In addition, AN and E_s are greatly influenced by wind speed: with increasing wind speed, E_s decreases and AN becomes unstable.

关键词：电磁环境测试系统高压直流输电线路气象参数高海拔天气条件传输线路技术人员环境参数

Influence Factors of Audible Noise Caused by Corona Discharge on UHVDC Transmission Lines Under High Altitude Condition

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高电压技术 2012年第12期38卷 3125-3132页

作者： TIAN Feng yu zhanqing ZENG Rong LIU Lei LI Min LI Ruihai Department of Electrical Engineering Tsinghua University Beijing 100084 China Electric Power Research Institute China Southern Power Grid Co. Ltd. Guangzhou 510080 China

Audible noises (AN) generated by corona discharges on ultra high voltage direct current (UHVDC) transmission lines is one of the key issues of UHVDC power projects. Experimental results were obtained synchronously by 10 Bruel Kjaer outdoor AN instruments under the full-scale test lines in National Laboratory for UHV Technology in Kunming at an altitude of 2 100 m. Long-term statistical measurements of the AN level were performed almost 24 hours a day and 5 ~ 6 days a week in 2 years. Influences of voltage, line configurations, temperature and humidity on the characteristics of AN levels were analysed. The measurement results show that the AN level rises with increasing line voltage, decreasing minimum conductor height and increasing bundle radius. The pole spacing has no significant influence on the peak value of the AN level. The AN level varies about ± 1 dB in the temperature range of 15~22°C, and no more than ±2 dB within 6.8?24.4 °C. The results also indicate that in a relative low range of absolute humidity, about 5 ~7. 99 g/m3,the AN level fluctuates slightly at different measurement points. However, in a relative high absolute humidity range, about 8~11. 5 g/m~3,the AN level decreases with the increase of absolute humidity.

关键词：高压直流输电线路电晕放电影响因素噪声高海拔高压直流输电工程绝对湿度电压升高

新一代高韧性直流输电技术(一):从器件、装备到系统

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中国电机工程学报 2024年第18期44卷 7321-7333,I0018页

作者：曾嵘赵彪余占清吴锦鹏魏晓光白睿航刘佳鹏屈鲁宋强清华大学电机工程与应用电子技术系北京市海淀区100084 北京怀柔实验室北京市怀柔区101499

构建高比例新能源、高比例电力电子化的新型电力系统迫切需要具有超强构网和主动支撑能力的新型直流输电技术。为此,文中秉承“一代器件、一代装备、一代系统”理念,提出新一代高韧性直流输电概念。增强型集成门极换流晶闸管(enhanced i... 详细信息

构建高比例新能源、高比例电力电子化的新型电力系统迫切需要具有超强构网和主动支撑能力的新型直流输电技术。为此,文中秉承“一代器件、一代装备、一代系统”理念,提出新一代高韧性直流输电概念。增强型集成门极换流晶闸管(enhanced integrated gate-commutated thyristor,IGCT-Plus)的半导体本征结构拥有超强的浪涌电流能力,将为高暂态耐受的换流器提供坚实的物理基础;新型模块化换向式换流器(modular commutated converter,MCC)拥有优异的软开关特性,将是高倍载直流输电系统的优选方案;IGCT-Plus和MCC作为核心器件和装备将支撑具有电压和频率强支撑能力的新型高韧性直流输电系统构建。文中从新型器件、新型装备到新型系统对高韧性直流输电技术进行全面论述,并对后续发展中存在的关键问题和技术进行分析和展望。提出的高韧性直流输电技术对支撑双高电力系统的安全稳定运行具有重要意义,有望成为未来电力传输中的崭新方式。

关键词：直流输电功率半导体器件门极换流晶闸管交直流换流器

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