Chao H.,Shenzhen Power Supply Co. |
Rong X.,Shenzhen Power Supply Co.
ICHVE 2016 - 2016 IEEE International Conference on High Voltage Engineering and Application | Year: 2016
This paper summarizes the current situation of the domestic and foreign power distribution switch cabinet sensing and monitoring technology. In view of the application occasions and different conditions of various kinds of PD monitoring how to select the detection method, according to the equipment to determine the status of the device to determine whether the PD present, that is combining with the ultrasonic wave, ground wave, HFCT, temperature and humidity and other monitoring means to monitor the running state of the power distribution switch cabinet. Finally, combined with examples, analysis and summarize the relationship between the discharge and the temperature and humidity and the state of the equipment, the results show that the proposed method is effective for the differential condition monitoring of switching devices. © 2016 IEEE.
Pan Z.,Nanjing Southeast University |
Gao C.,Nanjing Southeast University |
Liu S.,Shenzhen Power Supply Company
Dianwang Jishu/Power System Technology | Year: 2016
In order to promote electric vehicle development coordinated with power grid, this paper proposed a charging and discharging dispatch model of electric vehicles based on demand side discharge bidding. In day-ahead scheduling, electric company published time periods need to curtail load. According to prediction of electric vehicle users' behavior characteristics, load aggregator took maximum discharging capacity as goal to predict controllable capacity, and then participated in demand side discharge bidding. Electric company devoted to minimize load dispatching cost based on outputs and biddings of load aggregators. In real-time scheduling, load aggregator was aimed at maximizing its benefit through optimizing charging and discharging dispatch of electric vehicles. It could not only meet electric vehicle charging demand, but also reduce charging cost and dispatching deviation. Simulation result showed that the proposed dispatch model could play a role in peak load shifting. Prediction accuracy analysis could provide guidance for bidding decision of load aggregator. © 2016, Power System Technology Press. All right reserved.
Ming Z.,North China Electrical Power University |
Yingxin L.,North China Electrical Power University |
Shaojie O.,North China Electrical Power University |
Hui S.,Shenzhen Power Supply Co. |
Chunxue L.,North China Electrical Power University
Renewable and Sustainable Energy Reviews | Year: 2016
The nuclear accident that occurred in Fukushima, Japan has broadly affected the rapid development trend of the worldwide nuclear industry, causing many countries, including China, to adjust their nuclear policies. However, as the impact of the accident is fading away, nuclear policies are differentiating worldwide. Hence, analysing nuclear policies in different countries and their trends after the Fukushima accident has a practical significance of promoting the effective and safe development of the nuclear power industry. This paper focuses on the nuclear accident in Fukushima, Japan, and its wide impact. First, the changes of the developmental policies and the trends of the nuclear powers, including China, are summarised just after the accident in Fukushima occurred. Next, the nuclear power development of the nuclear powers and China in the last two years is analysed with real data. Finally, this paper systematically predicts the developmental direction of the global nuclear industry according to the actual nuclear development status in each country. © 2016 Elsevier Ltd. All rights reserved.
Zhao B.,Tsinghua University |
Song Q.,Tsinghua University |
Liu W.,Tsinghua University |
Zhao Y.,Shenzhen Power Supply Corporation
IEEE Transactions on Power Electronics | Year: 2016
This paper presents the transient dc bias and the current impact effects of a high-frequency-isolated bidirectional dc-dc converter (IBDC) in practice because the theoretical premise in the steady process cannot be satisfied strictly in the transient process. The transient characterizations of IBDC under the steady phase-shift (SPS) strategy are analyzed comprehensively, and the corresponding model is modified for all of the transient processes in the same and different power flows. Due to the existence of the dc bias, the current model in the transient process is different from the traditional model in the steady process, and the models are different with different operating conditions. On this basis, a transient phase-shift (TPS) strategy is proposed to improve the transient performance of the SPS strategy. Unlike in the SPS strategy, the voltages of the transformer are symmetrical in the TPS strategy, which causes that the voltage-time product of the transformer voltages is zero during a switching period, then eliminates the transient dc bias and improves the current impact, and further increases the response speed of the transient process effectively. Finally, comprehensive experiments verify the theoretical analysis. © 2015 IEEE.
Tian J.,Shenzhen Power Supply Co. |
Duan S.,Shenzhen Power Supply Co. |
Xu H.,Xi'an Jiaotong University |
Tang M.,Xi'an Jiaotong University |
Zhang G.,Xi'an Jiaotong University
Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering | Year: 2012
The influences of aging and temperature on the dielectric response (DR) characteristics of oil-paper insulation were investigated. Oil-immersed paper insulation samples were thermally acceleratedly aged at high temperature for different time periods. The polarization and depolarization current (PDC) test was performed on the samples with real time tracking during the aging process. The sample with different aging degree was tested by PDC at different temperatures, respectively. It is confirmed that aging and temperature both have significant effects on PDC curves. With aging or temperature rising, the PDC curves shift leftwards and upwards. It is considered that two types of interfacial polarization inside oil-paper insulation could be observed, one of which is the interfacial polarization between insulation oil and insulation paper, and the other is the interfacial polarization inside solid insulation due to its non-uniform structure. The former one responds faster under external electric field and is more suitable for insulation condition estimation, compared with the latter one. © 2012 Chinese Society for Electrical Engineering.
Wu Y.-T.,South China University of Technology |
Chu Q.-X.,South China University of Technology |
Yao S.-J.,Shenzhen Power Supply Co.
2013 IEEE International Wireless Symposium, IWS 2013 | Year: 2013
A dual-band printed slot antenna for wireless communication terminals is presented. It consists of two pairs of C-shaped slot and T-shaped slot and six pairs of slit. The C-shaped slots are fed by two 50-Ω microstrip lines. The antenna can provide two wide operating bands centered at 2.50GHz and 3.66GHz, to cover WLAN/2.5-GHz and the 3.5GHz WiMAX bands respectively. The isolation of the prototype are less than -20dB and -25dB across the above bandwidth in turn, while six pairs of slits play an important role in reducing mutual coupling. Good performances of proposed antenna over the operating bands are also obtained. The discussion shows that the antenna can be considered as a good candidate for multiple input multiple output (MIMO) systems. © 2013 IEEE.
Ding D.,Sichuan Electric Power Research Institute |
Ding D.,Tsinghua University |
Gao W.,Tsinghua University |
Yao S.,Shenzhen Power Supply Co. |
And 2 more authors.
Gaodianya Jishu/High Voltage Engineering | Year: 2013
The understanding of the excitation mechanism of ultra high frequency (UHF) electromagnetic waves (EW) is essential for applying UHF method to partial discharge (PD) detection. Since the EW induced by PD in gas insulated switchgear (GIS) contains not only transverse electromagnetic (TEM) wave, but also high-order transverse electric (TE) and high-order transverse magnetic (TM) waves, we analyzed the proportions between the TEM wave and the high order waves, as well as the influence of the PD position on this proportion, using the finite different time domain (FDTD) method. According to the unique characteristics of the waves, they are separated only approximately. It is found that the high-order mode is the main component, more than 70%, of the electric field around the enclosure of GIS, and that with the increasing distance between PD source and inner conductors, the low frequency (below about 800 MHz) component of EW decreases, but the high frequency component (above 1 GHz) increases, meanwhile the proportion of high-order components in EW could reach 77% from 70%. It concluded that the closer the PD source to the enclosure is, the easier high order EW may be excited.
Zeng X.-J.,Shenzhen Power Supply Co. |
Liu X.-M.,Shenzhen Power Supply Co.
Gaoya Dianqi/High Voltage Apparatus | Year: 2013
The paper explains the on-site PD test method, including UHF and ultrasonic. The illustrated catalogue got from UHF and ultrasonic PD detection by a lot of on-site tests. Meanwhile, through combining the illustrated catalogue of PD with the practical location of GIS, the diagnostic illustrated catalogue for GIS on-site PD testing is given. An application example is given to verify the effectiveness of such diagnostic criteria.
Ming Z.,Shenzhen Power Supply Co. |
Qiangqiang S.,Shenzhen Power Supply Co.
Open Electrical and Electronic Engineering Journal | Year: 2014
The paper proposes the use of digital watermark based authentication for intrusion detection in IEC 61850-automated substations. The watermark can be embedded into the Least Significant Bits of the measurements without visible deterioration in precision. When Intelligent Electronics Devices gets measurements, the watermark in the measurement can be retrieved to determine whether it has been attacked and detect malicious intrusion. The proposed approach is appropriate for the time critical and resource constrained applications in substation automation system for its simplicity. Numerical simulation shows that the process latency and error incurred by watermarking is acceptable and will not impact performance of protective function in IEC 61850 automated substations. © Ming and Qiangqiang.
Sun G.,Beijing Sifang Automation Co |
Shi B.,Beijing Sifang Automation Co |
Zhao Y.,Shenzhen Power Supply LLC |
Li S.,North China Electrical Power University
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2015
A protection configuration strategy and fault location method of the demonstration project of flexible DC distribution system in Shenzhen is studied. Firstly, focusing on the topology structure of the project, the protection area of DC distribution network is divided. Secondly, an overall protection configuration strategy is presented considering MMC and the system's faulty characteristics. Thirdly, as the new feature of the load and micro grid being connected with the DC line with "T" type, the protection configuration and fault location method of DC line single-pole fault, double-pole fault and broken line fault is proposed. Lastly, the simulation model of MMC based DC distribution grid is built on PSCAD/EMTDC, and the simulation results verify the effectiveness of the protection configuration strategy and the correctness of the fault location method. © 2015, Power System Protection and Control Press. All right reserved.