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Wang D.,Shandong University | Wang X.,Shandong University | Xiong L.,Shandong Kehui Power Automation Co.
2015 18th International Conference on Electrical Machines and Systems, ICEMS 2015 | Year: 2015

Linear switch reluctance machine (LSRM) has been a promising alternative for linear application systems despite its low force density and high force ripples. In long stroke conveyor applications, the stator of LSRM should be laminated requiring no gap or interruptions, being a difficulty in practical use. This paper presents a dual stator LSRM with magnetically isolated rectangular segments. The presented machine consists of a simple concentric winding but not similar to the conventional LSRM windings, being suitable for long stroke transportations and exhibiting high reliability and low cost. The machine design procedure is given and the key dimensions which crucially affect the machine performances such as force profile, average thrust and force ripple are discussed. It has been demonstrated that the presented machine has gained superiority over conventional LSRM in terms of higher propulsion force density and low cost. © 2015 IEEE.

Li F.,Hefei University of Technology | Xu B.,Shandong University of Technology | Gong S.,Shandong Kehui Power Automation Co.
Dianli Xitong Zidonghua/Automation of Electric Power Systems | Year: 2012

Arc reflection method (ARM) is a kind of cable fault locating method widely used nowadays. Pulse echoes are subject to interference coming from the arc voltage fluctuation on fault spot when fault cable is tested using arc reflection method. For this reason, it is difficult to locate the fault spot by identifying the disordered features of pulse echoes. This paper analyzes the causes of arc voltage fluctuation when arc is burning as well as the features of the disturbed pulse signals, and then analyzes time-frequency distribution of the disturbed pulse signals using empirical mode decomposition (EMD). It proves that pulse signals and arc voltage fluctuation received in the same time can be completely separated according to their arithmetical mean characteristics in a specific period of time. A new extraction algorithm of pulse signals is proposed. It can be used for identifying arc reflection cable fault locations based on arithmetical mean characteristics of the distributed pulse signals over a specific period time. An empirical mode decomposition filter is also proposed. This method overcomes the difficulties in choosing signals basic functions and signals decomposition levels. It is fully data-driven, so it has strong adaptive capacity. Results of pulse signals extraction by recorded real test data proved the proposed algorithm. © 2012 State Grid Electric Power Research Institute Press.

Xu B.,Shandong University of Technology | Xu B.,Shandong Kehui Power Automation Co. | Xue Y.,China University of Petroleum - East China | Li T.,Fujian Electric Power Company | And 3 more authors.
Dianli Xitong Zidonghua/Automation of Electric Power Systems | Year: 2012

With the massive integration of distributed generators (DGs) and the ever-increasing demand on power supply quality and system efficiency, the protection and control of the distribution network is facing new challenges. The traditional centralized and local measurement based protection and control methods have either slow responses or poor performance due to limited information inputs. A wide area measuring and control system (WAMCS) able to support all kinds of centralized, local and distributed intelligence (DI) control methods and provide a unified and open platform for monitoring, protection and control applications of the smart distribution grid is proposed. DI based applications in WAMCS, such as DGs interconnection control, wide area protection, fast fault isolation and the service restoration and self-healing solutions for earth faults in a non-effectively earthed network, are presented. With further progress and improvement of the technologies, the WAMCS and its applications will provide a solid foundation for the development of smart distribution grids. © 2012 State Grid Electric Power Research Institute Press.

Li F.,Hefei University of Technology | Xu B.,Shandong Kehui Power Automation Co.
Dianli Zidonghua Shebei/Electric Power Automation Equipment | Year: 2011

The current and voltage response of surge discharge circuit to impulse flashover voltage test system is analyzed. When only low frequency transient components are considered, the lumped parameter model of the surge discharge circuit of power cable fault locator is constructed based on the T-type equivalent network of uniform transmission line. According to the geometry and material specifications of power cable, as well as the relationship between its lumped and distributed parameters, the approximate expressions of current and voltage response, as well as the expressions of current attenuation coefficients and oscillation frequency of current response, are deduced. When the series resistance in surge discharge circuit is zero, the current and voltage response are approximately the second-order decaying vibration process. When the series resistance is not zero, the current response to the secondary impulse method is the over-damped negative-exponent decaying process. The results of model calculation are consistent with the experimental results, verifying the correctness of the modeling.

Li F.,Hefei University of Technology | Xu B.,Shandong University of Technology | Yan T.,Shandong Kehui Power Automation Co.
Dianli Xitong Zidonghua/Automation of Electric Power Systems | Year: 2014

Arc reflection method (ARM) is currently widely used power cable fault location method used. It is very important to understand the cable fault arc resistance dynamic characteristics for ARM technology and product development. The cable fault arc resistance characteristics during ARM testing were analyzed based on theoretical studies and experiments. A universal Mayr arc model is developed for cable fault arc simulation. This arc model can be used to calculate the instant arc resistance and simulate the change of cable fault arc during ARM testing. The experimental results show that the average relative error of arc resistance between the simulated results with the proposed arc model and actual measurement data is less than 12%, and the maximal relative error is less than 29%. The results meet the requirement of ARM cable fault location simulation. ©2014 State Grid Electric Power Research Institute Press

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