Advanced Materials Research Vols. 614-615

Abstract: For optimal planning distributed generation (DG) in the distribution network well, this paper proposed the approach to optimal configuration DG on the distribution planning platform(DPP). This paper analyzed the zone selection for placement DGs, and built the selective zone’s network on the DPP. The site and size of DG was determined according to the node priority, the annual minimum electric power loss and maximum economic benefit. Moreover, the power flow was calculated after and before placing DGs, and the results were showed on the DPP, which included power flow, node voltage, and the siting and sizing of DG. By the planning DG results under different load instance, it is more intuitive to analyze the node voltage, branch flow and loss, and to observe the site and size of DG on the DPP. The method provides the necessary support of data and technology to optimal planning DG.

Abstract: The power, voltage and current will change along with the change of grid’s operation mode; however, the line resistance is unchanged. This paper analyzed the limitation and inadaptability of the existed methods used for anti-electricity-theft. And most of the criterions are based on the variable electrical quantities. In order to establish a criterion that can find out the position of electricity-theft accurately, it chose line resistance as a reference value, and calculated the equivalent resistances of each node and branch combining with the actual measurement system. To verify the validity of this criterion, a medium and low voltage distribution network was structured in the Matlab/Simulink simulation platform. The results, which are basically consistent with the actual situations, show that the criterion based on line resistance can well investigate electricity-theft, and also verify that the introduction of this method will bring great benefits to engineering applications.

Abstract: In this paper, the models of the multi-bundled conductors are constructed by finite element method. The wake effect of aerodynamic parameter of sub-conductor of the windward side relative to the leeward side is studied. The numerical results are given by using the 4th order Runge-Kutta method. Similarly, the proposed model can be added to the different aerodynamic loads on each individual sub-conductor of a bundle conductor during the simulation of galloping. Thus the numerical results are much closer to the actual movement of galloping and provide a useful reference for anti-galloping.

Abstract: Power transmission is a key link in power system. As the increase of power supply, the transmission capacity of the lines should be enlarged too. In the developed area, the right-of-way for transmission line is hard to be obtained. And converting the existing HVAC overhead transmission lines using HVDC technology could enhance the transmission capability. There are three possible plans for different HVAC transmission lines: single-pole HVDC, bi-pole HVDC and tri-pole HVDC.

Abstract: The trend towards using IEC61850 standards in feeder terminal unit (FTU) design is inexorable, but at present in China, IEC60870-5-104 is mostly used in distribution automatic system (DAS) information exchange. Thus it can be seen that IEC61850 standard will coexist with IEC60870-5 standard for a long time. IEC61850-80-1 provides the method of exchanging information from IEC61850 CDC-based data model using IEC60870-5-101 or IEC60870-5-104. This paper makes a brief analysis on the structure of DAS based on IEC61850, proposes the information model of FTU in accordance to IEC61850 and maps the information model to IEC60870-5-104 using IEC61850-80-1, which takes the advantage of IEC60870-5-104’s excellent real-time performance to realize peer-to-peer communication between FTUs.

Abstract: The dynamics force of iced-conductor is the driving force of galloping; its variation is depended on the aerodynamic character of iced conductor. The aerodynamic character of iced conductor is the key factor of galloping of iced-conductor, but the result of theoretically analysis and numerical simulation isn’t suited for the requirement of transmission line project. In the paper, basing on the theoretically analysis and numerical simulation, the simulation tests in wind tunnel of D-shaped iced conductor is stetted up and put into practice under different wind speed and iced thickness, and then the systemic study is carried into execution. The result of research is indicated that there is a better coherence between the numerical simulation and experiment test, and the variation rules of parameters is obvious with the different iced thickness, the result of numerical simulation is the beneficial supplement to the experiment test. The result can not only provide the original date for the galloping analysis, but also validate the affectivity of numerical simulation, support the research of mechanism and control of galloping.

Abstract: In recent years, with the development of smart materials as well as smart structure technologies, and the research on piezoelectric energy harvesting technology deepens, the low power application circuit along with highly-efficient storage circuit optimization and design has become one of the essential parts in this field. The author made a systematic conclusion on the piezoelectric energy harvesting circuit, and put forwards a feasible plan for sustainable research in the future.

Abstract: This paper listed the mathematic model of transmission line firstly, and PSASP was used to simulate the fluctuate voltage of transformer substation which affected by wind generate electric power capacity which combined to the grid changed and the power flow of XINJIANG sent into GANSU changed. At the end, the conclusion and construction of improve grid running state was presented.

Abstract: In this work, we report the design of a new instrument including one heat pulse circuit and three temperature measure circuits. Heat pulse control circuit can control the heating time of heater strip. The heating power is 0.5W and the duty time of every heat pulse is 8s. Three temperature measure circuits can measure the change of stratum’s temperature before and after accurately. The temperature resolution is 0.001°C, precision is 0.01°C and sampling rate is 1 Hz. The instrument can save the temperature data for every measure process. It is also provided with the data communication interface. The data saved in the instrument can export to computer through the interface. The instrument can measure the stratum’s temperature easily and reliably. The instrument will play a role in the studies of hydrogeology and environmental geology besides the application of Shallow Geothermal heat

Abstract: Discriminating measurement of strain and temperature is demonstrated by using a long period fiber grating according to its spectrum characteristics. The resonant wavelength of the first and third-order loss peak is selected, and temperature and strain sensitivity of each resonant wavelength are experimented. The self-wavelength shift resulting from parameter variation can be obtained by observing its corresponding spectrum. The temperature and strain sensitivity are calibrated. Both wavelengths have good linear response of temperature and strain in a certain variation range. Then, slandered matrix equation is set up and solved according to the corresponding parameter. Experimental results show root mean square deviation of ±16με and ±0.62°C for strain and temperature, respectively. This method can realize discriminating measurement of strain and temperature avoiding cross sensitivity. System accuracy is also improved efficiently.