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The power system loss is a very important technical and economic indicator in power enterprises. In a system, there are two types of losses: technical losses and non-technical losses (commercial losses). Out of the total system losses, technical losses can be reduced more directly and effectively. This paper focuses on the analysis of the variation and contributing factors of technical losses of each voltage class in Hubei power grid. As a result, main reasons and solutions for reducing technical losses are figured that provide a better understanding of weakness and loss composition of Hubei power grid, and are useful for power enterprises that intend to reduce electric losses as a benchmark and as a background in the planning purposes.

The “two-tickets” system of electric power enterprises is an important organizational measure to ensure operation safety of electric power production site. In the actual electric power production, the operation safety accidents caused by “two tickets” signed not in accordance with regulations or by others occur from time to time. At present, electric power enterprises mainly rely on manual inspection to verify the authenticity of “two tickets” signature, which has the shortcomings of more human resources investment and low efficiency. In this paper, a signature identification method of “two-tickets” based on siamese convolutional neural networks is proposed. The proposed method introduces image processing, max-pooling, batch normalization, and dropout technologies, and effectively combines convolutional neural network and siamese network, which can effectively improve the accuracy of “two-tickets” signature identification. The results show that the proposed method is more accurate than k-nearest neighbor method, naive bayes method, decision tree method and support vector machine method. The proposed method can be applied to the “two-tickets” signature identification in electric power enterprises.

Line loss is an important criterion for evaluating economic operation level of power grid. This paper takes EZ Power Grid as a typical example and points out some of its general problems that are also common problems in current power grid. The evaluation method for power loss reduction are introduced, including economic operation for transformers and power lines, evaluation method for transformers and power lines, power saving after transformation of main transformers, reactive power compensation devices and power lines. Then, based on the analysis of EZ Power Grid operating data, evaluation of power loss reduction is mentioned. Finally, some suggestions to reduce power loss in EZ Power Grid are put forward, which can also be used for references by other regions.

The wide application of cable brings a lot of charging power, which leads to the surplus of reactive power and the high voltage of the system. This paper discusses the theoretical calculation of charging power of the cable in detail, and analyzes the influence of charging power on voltage and reactive power under small load mode combined with the specific example of Fenghuangshan power supply area in Wuhan, Hubei Province. Finally, some control measures such as installing inductive reactive power compensation device are proposed.

The synchronous interconnection between Chongqing and Hubei power grid is planned to be unsynchronised by back-to-back voltage source converter based high-voltage direct current (VSC-HVDC) project, which has great impact on the operation characteristics of Hubei power grid. In this study, the basic information of back-to-back VSC-HVDC project was introduced. The influence of this project on the operation characteristics of Hubei power grid was analysed in detail, including power flow, short-circuit current, transient stability and frequency characteristic. The corresponding grid reinforcement measures were proposed to solve power flow over-limit and transient instability problems caused by this project. The study has some reference value for the planning and operation of Hubei power grid and the design of other similar HVDC transmission projects.

This paper proposes the method of optimizing the Xgboost model by Quantum-behaved Particle Swarm Optimization (QPSO), and validates its effectiveness in the context of network intrusion detection. We preprocess the data set first, and then use QPSO to optimize the parameters of the Xgboost model. After that, we use the test set to evaluate the optimized model. The experimental results show that the Xgboost model optimized by QPSO has good performance in terms of precision, recall rate and average precision, and is better than the unoptimized Xgboost model and grid search method.

Due to the lack of competition and unbalanced demand supply situation in current electricity market, deregulating electricity sale market has become the core of new electricity reform. The electricity market pattern of "multi-buyer-multi-seller" will be formed by opening up electricity sale market. In this paper, the construction and development of Hubei electricity sale market is introduced in detail. The first batch of electricity sale companies in Hubei Province is analyzed. The development stage of electricity sale market in Hubei Province is studied, including primary stage, growth stage and mature stage. The situation and suggestions of each stage are analyzed. The business development of electricity sale market in Hubei Province is proposed. The research results can provide a reference for other provinces in China to carry out electricity sale market reform.

Quality service is one key work of power supply companies. Customer complaints contain a lot of intrinsic feature information, such as customer demand and service defects. Analysis of customer complaint data can effectively identify service shortcomings and provide guidance for improving quality service. In this paper, complaint behavior of electric power customers are analyzed from three aspects, including complaint contents, complaint time and complaint areas. The related factors and risk index of customer complaints are studied. The suggestions to reduce complaints are proposed. The conclusions can provide a reference for quality service of power supply company.

Hubei-Chongqing Back-to-back VSC-HVDC is planned to go into operation in 2019 ， and the reinforcing projects will go into operation synchronously to solve the problems of power flow evacuation, transient stability and dynamic stability. In this paper, the impacts of the reinforcing project of Hubei-Chongqing Back-to-back VSC-HVDC are analyzed in the aspects of short-circuit current, power flow evacuation and transient stability characteristics, on the basis of which the corresponding control strategies are proposed. This work can provide certain reference value for the security and stability of Hubei Power Grid after commission of Hubei-Chongqing Back-to-back VSC-HVDC and its reinforcing project.

Voltage curves similarity can be used to verify distribution network topology. However, the voltage curves may be affected by voltage regulation which will result in the inaccuracy of similarity calculation. A method which can be used to calculate the similarity of voltage curves when considering the impact of voltage regulation has been proposed in this paper. Kolmogorov-Smirnov test is used to detect the outliers between the voltage curves of two distribution transformer. Two case studies have been carried out to show the correctness of the method. Discussions have also been made. The results show that the method proposed in this paper will not be affected by voltage loss. The results also show that even if there are extreme outliers, whether the voltage curves of the two transformers are similar is still should be decided by the results of the subsections.

Heavy load and overload distribution transformers will have a heavy effect on power supply reliability and quality service. In this paper, heavy load and overload of 10kV distribution transformers in regional power grid of Hubei Province from January 2017 to June 2018 are analyzed from different dimensions, including time and area. The risk prediction of 10kV distribution transformations during the peak summer period in 2018 is carried out, including heavy load, overload, high failure rate and low voltage. The conclusions can provide a reference for better understanding of heavy load and overload distribution transformer and guiding operation and planning of distribution network.

In this paper, load rate of 3917 sets of 10kV distribution transformers in regional power grid of Hubei Province during 2016 is statistically analyzed from four aspects, including the annual maximum load rate and the annual average load rate of single distribution transformer, as well as the mean of the daily maximum load rate and the mean of the daily average load rate of all distribution transformers. The loss of single distribution transformer and actual loss of all distribution transformers in regional power grid are studied. The conclusions can provide a reference for better understanding of actual operation of distribution transformer, and guiding operation and planning of distribution network.