Advanced Materials Research Vols. 354-355

Abstract: The model of GEP in carbon market is established by introducing the carbon economy index proposed in this paper to traditional GEP model. Considering the operation experience of European Union Emission Trading System (EU ETS), the proposed index mainly consists of the CO2 emission load and the carbon price, which works as two forms in the established model: the carbon income in objective function and the CO2 reduction constraint in constraints. Especially, this paper divides the CO2 reduction constraint into two parts working in different planning period, so as to provide the flexibility and the result control for the planning. And the simulation shows that the GEP in the carbon market can guide the power structure adjustment and reduce CO2 emissions.

Abstract: Interharmoics are the signals whose frequencies are between two harmonics. Besides the usual characterics of the harmonics, interharmonics will influence the present harmonic compensating equipment, and then result in failure compensation. Therefore, precise detection of interharmonics is very important and significant. Complex modulation Zoom-FFT (ZFFT) based on complex analytical bandpass filter is introduced in the real-time detection of the power system. Contrasting to the traditional zoom spectrum algorithms, the proposed algorithm is more suitable in the intensive spectrum analysis. Detailed theoretical analysis and simulation results are presented. The effectiveness of this algorithm is verified.

Abstract: A new current detecting algorithm is proposed in the paper, which is applied in an improved hybrid active power filter. The filter equipment can be applied in high voltage system to suppress harmonics and compensate reactive power. The topology and filtering principle of the filter equipment is given. The harmonic suppressing function is adopted to analyze the influence by the grid impedance, quality factor and losing resonance of the resonance circuit. The feasibility of the proposed system is validated in theory. A single-phase current detecting method is also proposed. The corresponding current control is formed combined the DC-link current detecting method. The simulating results prove that the system is feasibility and the current control is validity. Harmonic and reactive power are suppressed well.

Abstract: Gene Expression Programming (GEP), which is suitable for transformer fault diagnosis Classification, is combined with transformer oil dissolved gas analysis (DGA), and also a method of transformer fault diagnosis based on self-adaptive GEP classification algorithm is proposed. We choose 400 groups of DGA measured data which includes a variety of failure and does not redundant as the training samples and test samples of the GEP classifier. A large number of diagnostic examples show that the proposed self-adaptive classification GEP is suitable for transformer fault diagnosis, and its performance is better than using Naive Bayes (NB) classifier, BP network and Immune classification.

Abstract: In view of a large number of distributed generators penetrated into distribution network, an improved hierarchical island operation was proposed to make the DG play the role as backup power supply in the service restoration of the distribution network; As the renewable distributed generators was strongly advocated, A new mathematical model was proposed to make full use of them. The service restoration problem is a constrained multi-objective optimization problem, a new algorithm which was the combination the heuristic algorithm and multi-agent evolutionary algorithm was proposed, it improved the multi-agent evolutionary algorithm with the Niche technologies to ensure the variety of the populations in the post-optimization and used the adaptive updating strategy to improve the convergence speed. The results of a case show feasibility and correctness of the model and the algorithm.

Abstract: Condition Monitoring Agent (referred to as CMA) inherits and develops the concept of "concentrator" and "monitoring station", and play a connective role in the condition monitoring field of power transmission and transformation system. This paper describes the various concepts associated with the CMA and the CMA's design principles, general requirements and functional design.

Abstract: According to the principle of PSS2B model of IEEE, reason for producing reverse regulation for PSS is analyzed. Through analysis of the frequency characteristic, it is put forward that setting power matching coefficient and filter parameters can reduce the influence of antiregulating. The model of simulation is established, which is based on the Matlab. Result of simulation shows that the method is valid. It can make the method of setting PSS parameters more perfect.

Abstract: Energy-saving generation dispatching is a trial generation dispatching mode in China, reducing energy consumption is the core idea of energy-saving generation dispatching. In this paper, the conception and effect of energy-saving generation dispatching were introduced. The models of energy-saving generation were classified, and some typical models were analysed. Due to the problems brougt about by energy-saving generation dispatching, the modes and economic compensation mechanism were paid attention, this paper analyzes some modes and economic compensation mechanism of energy-saving generation dispatching. Some new problems occured after energy-saving generation dispatching applied were presented and analyzed. Lastly, the development direction of energy-saving generation dispatching is proposed, which lays the foundation for future research.

Abstract: How to determine spinning reserve reasonably in electricity market is one of the key questions which guarantee the security and reliability of power systems. For this issue, based on bi-level programming theory, an optimal model of spinning reserve is established in this paper. In this model the generation cost minimization and the reserve cost minimization are the upper level and lower level optimization object separately, and the network and “N-1”security constraints of the power system are also considered. The determination of reserve capacity and the reliability level are related, and the reserve rate of each unit is determined. And an IEEE-14 nodes test system case is used to demonstrate the feasibility and rationality of this proposed model.

Abstract: Harmonic pollution monitoring and control is the key to an accurate estimate of harmonic impedance, and thus an accurate assessment of public connection points of the harmonic emission level. This paper analyzes the link under the star-shaped and triangular three-phase asymmetrical power systems derived established a three-phase unbalanced power system harmonic impedance matrix estimation model. Model is based on a large number of systems and load the public connection point of the simulation data, the real and imaginary part of the harmonic impedance by opening and using grouping multiple linear regression method, on the system side harmonic impedance matrix to estimate the value of each element. Simulation and error analysis shows that the model obtained is more accurate and effective.