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A set of measurement system for the testing of transmission lines, composing of wireless center station, wireless current acquisition and transmission nodes, wireless voltage acquisition and transmission node, was designed, which was based on wireless communication. The high speed wireless bridge working at 2.4GHz together with the clock synchronization module based on the IEEE1588 communicating protocol were both employed for the communication and time synchronization separately. The measurement system has data storage, waveform display, data analysis, automatic report generation and other functions. The measurement system can greatly reduced arrangement of cables, thereafter improved the test efficiency.

The software of measurement system for the transmission line debugging was designed. The transmission line is based on wireless communication. This software of measurement system is composed of acquisition controller software system and center station software system. The measurement system realized the function of data storage, waveform display, data analysis, automatic report generation and others. The field experiments were conducted at a 500kV substation in a Power Grid. The experiment proved the validity and reliability of the measurement system. The measurement system can avoid complex wiring work in substation debugging field, thus improve the experimental efficiency.

±1000kV DC wall bushing is a complex insulation system working in different conditions, such as DC, AC and polarity reversal. No matter what kind of conditions, the space charge effects on the electric field distribution of the bushing are remarkable. A finite element model for ±1000kV DC wall bushing is established based on space charge theory, to analyze the electric field distribution in different conditions, especially when polarity reversal occurs. The research results provide useful references for the electric field analysis and insulation optimization of UHV (ultra high voltage) DC wall bushings.

The energy storage technique is one of the most effective means for the real-time wind power regulation. Firstly, this paper discussed the operation mode of energy storage system for real-time wind power regulation. At the same time, we proposed that the energy storage system applied into the real-time wind power regulation should be of the properties of high power density, high energy density and long cycle life. By analyzing the properties of battery and supercapacitor, we arrive at the conclusion that the battery-supercapacitor hybrid system obtains the enhanced characteristics to meet the performance requirement for energy storage system. In order to achieve the real-time wind power suppression, we carried out a comparative research on the topology of battery-supercapacitor hybrid system. The operation mode of each topology was discussed. From the standpoint of practical engineering, the merits and deficiencies of each topology were explored.

Large-scale wind farm connecting to the grid will affect the stability of the grid, therefore dynamic reactive power compensation devices need to be installed at the wind farm in order to reduce the negative impact after connecting to the grid, andimprove the low voltageridethrough capability of the grid system wind turbine. Simulation models of a wind farm and SVCare built in PSCAD. In different fault location, simulations are carried out respectively to analyze the effect of SVC on LVRT. The results show that SVC can effectively improve the LVRT capability.

Building data center and data mining of wind power is essential to detect potential safety problems. The traditional data centers requires a lot of computing device and also have some disadvantages, such as limited scalability, high cost and low reliability. This paper presents the remote fault diagnosis system of wind power based on cloud computing and thoroughly analyzes construction demands and functional structure. Experimental results show that this system can effectively analyze mass monitored data, accurately assess equipment failure and reduce costs and the operating costs. This provides a new idea for cloud computing applied to data center of wind power.

Research on remote fault diagnosis of wind power has great significance of protecting grid security and secure operation of wind farm This paper presents the remote fault diagnosis system of wind power based on cloud computing and thoroughly analyzes construction demands and functional structure. Experimental results show that this system can effectively analyze mass monitored data and accurately assess equipment failure. This provides a new idea for cloud computing applied to wind farm fault diagnosis.

Along with the UHV construction scheme, China will form a large number of transmission lines which have the characteristics of the ultra-high voltage, large-capacity, long-distance. Because the UHV power grid transmission line parameters and the structure of the grid and the transformer are different from the other power net, Geomagnetic storms will affect the UHV power grid more, the work have important significance to the assessment of the ultra-high voltage power grid level and influence. The impact of different storms on the grid are also different .Based on the power flow mechanism of the GIC, different data and network parameters of geomagnetic storms, the evaluation model of the GIC is established ,we assess the result of the GIC induced by the geomagnetic storms happened on November 2004 and December 2006 in the 2020 planning ultra-high voltage power grid, find out the greatest impact transformer substation and the timing analysis results of the grid compare the different impact of different storm.. The comparison of the analysis results is helpful for understanding the different kind geomagnetic storms and the regional features of GIC.

To decrease short-circuit current, adjusting the power network operation by breaking transmission lines is the most economic and convenient measure. For large power grid, breaking transmission lines has thousands of combinations, so it's very difficult to find the best combination in a short time. Firstly, this paper formulated the sensitivity relationship between transmission line outage and impedance change. Then preliminary combinations schemes of transmission line outage were selected according to the sensitivity. Index values of factors were given using the fuzzy control evaluation. Finally, this paper determined optimal scheme from maximum priority and accomplished the accessorial intelligent optimize system of limiting short-circuit current. The rapidity and rapidity of the proposed control strategy was verified by calculating the actual power grid.

In view of the diversity, complexity and magnanimity of information data in the operation status of new energy power plant, the data mining technology is applied to fault diagnostics. On this basis, the overall process of fault diagnostics methods including clustering analysis, fault rule mining, fault modeling and other mathematical statistical theories is designed. The logical relationship between massive data is redefined at a deeper level. And the most effective fault characterization is extracted. The correctness and validity of the method are proved by comparing the curve of the fault characteristic parameter prediction results with the field measurement results. This method has high data processing efficiency, effectively improves the reliability and accuracy of fault diagnostics and early warning. And it provides a strong guarantee for the safe operation of the new energy grid-connected.

Near infrared spectra of 99 lamb meat samples from three pasturing areas and two farming areas of China were scanned and analyzed to seek a cheap, rapid and effective method for lamb meat origin traceability. Two chemometric methods including linear discriminant analysis based on principal component analysis (PCA+LDA) and partial least squares discriminant analysis (PLS-DA) were used to develop the discriminate models. It was showed that there were significantly differences among the lamb meat samples from five regions based on NIR spectra after second derivative (Savitzky-Golay, 9 point) and multiplicative scattering correction (MSC) transformation in the whole wavelength. The discrimination of two models was best for classification of pasturing area and farming area, with both correctly classified by 100%. The correct classification rate of samples from five different regions using PCA+LDA model was 91.2%, higher than using PLS-DA model (76.7%). These results demonstrate that near infrared reflectance spectroscopy (NIRS) combined with chemometric analysis can be used as an effective method to classify lamb meat according to its geographical origin.

To clone and characterize the p43 cDNA from muscle larvae cDNA library of Trichinella spiralis (Ts) Chinese isolate.PCR technique was used to amplify the target cDNA from muscle larvae cDNA library. After cloned in pMD18T vector, it was transformed into E. coli NovaBlue. The positive clones were sequenced and the cDNA was cloned into pET28a expression vector. After induced by IPTG, the inclusion body of the recombinant protein was purified and re-natured. The deoxyribonuclease II (DNase II) activity of the recombinant protein was tested by hydrolyzing XDNA.Open reading frame (ORF) of the p43 cDNA was successfully cloned from the muscle larvae cDNA library of the Chinese Ts, there were mutations of two nucleotides in the ORF of the Chinese Ts p43 cDNA comparing with that from U.S.A. isolate at the positions 210 and 604, namely, C and A in the USA isolate but T and G in the Chinese isolate. Considering that three authors had cloned the same p43 cDNA from the USA isolate and six groups (including this team) had also obtained the same sequence from the Chinese isolate, the mutation of the two nucleotides was considered as the single nucleotide polymorphic (SNP) marker of the Chinese Ts isolate. The DNase II activity of the recombinant protein was successfully detected by hydrolyzing lamdaDNA.The p43 cDNA was successfully cloned from the muscle larvae cDNA library of the Ts Chinese isolate. Two SNPs were found in the nucleotide sequence. The DNase II activity was proved.