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In this paper, the security and consumption problems of large-scale wind power integration to electric grid are briefly introduced, focusing on serious events that many installations went off the grid, failing to “ride through fault” (RTF), which happened successively since 2011. Then the mechanisms of coordinated development between wind power and electric grid are discussed, and suggestions on management & technical measures are proposed to realize a great friendly wind farm which can be developed in a scientific, healthy and sustainable manner.

Estimation of Signal Parameters via Rotational Invariance Techniques (ESPRIT) is applied to analyze the interharmonics in Electric Power System (EPS). First, the signal received by one A/D convertor forms a signal vector through time shift; second, the number of sinusoidal components which compose the analyzed signal is estimated by calculating Minimum Descriptive Length (MDL), and then ESPRIT utilizes the rotational invariance of two sampling linear arrays to obtain frequency information by Total Least Squares (TLS) algorithm; and finally the rest amplitudes and phase angles are estimated by a simplified Support Vector Regression Machine (SVRM). TLS-ESPRIT aided by MDL as a super-resolution algorithm can overcome resolution limit and achieve better results compared with FFT and PRONY algorithms. Computer simulations prove that the proposed method is feasible and applicable.

A multiresidue immunoassay method for determination of Fluoroquinolones (FQs) residues has been developed. For this purpose, NHS ester technology was employed to synthesize the immunogen and coating antigen of Norfloxacin (NFLX). SDS-PAGE, UV-visible spectra and Infrared spectra identification showed that the artificial antigen was conjugated successfully. Based on the square matrix titration, an icELISA method was established. The dynamic range in assay buffer was from 0.038 to 112.8 ng/mL, with LOD and IC50 value of 0.02 ng/mL and 1.2 ng/mL, respectively. This assay showed a high cross-reactivity to Ciprofloxacin (86%), Enrofloxacin (75%), Difloxacin (63%), Sarafloxacin (57%) and Pefloxacin (33.8%). The chemical effects on assay performance showed that the physiological pH (7.4) in assay buffer pursued the maximum absorbance (Amax) and the most sensitive IC50 values. The results suggest the artificial antigen was synthesized successfully, and the established immunoassay could be used for simultaneous detecting of Norfloxacin, Ciprofloxacin, Enrofloxacin, Difloxacin, Sarafloxacin and Pefloxacin residues in animal-original food samples.

A rapid indirect competitive ELISA (icELISA) for the determination of enrofloxacin (ENR) residue has been developed. EDC method was employed to synthesize the artificial antigen of ENR-BSA, and anti-serum produced from rabbits was selected. Based on the square matrix titration, an icELISA method was developed with the polyclonal antibody. The Linear range was from 0.006 to 31.5 ng/mL, with LOD and IC50 values of 0.003 ng/mL and 0.45 ng/mL, respectively. Except for a high cross-reactivity (105.2%) to ciprofloxacin, negligible cross-reactivity to other compounds was observed. The recoveries of ENR were in the range of 98.3-127.5%, 85.7-112.5% and 97.4-103.8% for chicken muscle, liver and kidney, respectively. Therefore, this assay has the potential to be incorporated into a quantitative monitoring program for the rapid screening of ENR residue in food.