With the proposal of China’s “dual carbon” goal and the construction of a novel power system, how to reduce the total carbon emissions of power generation enterprises and increase the share of renewable energy generation is an important issue facing China at present. In this paper, the conventional electric energy market trading paradigm is improved, and an optimization model for electricity trading considering carbon markets and renewable energy quota system is proposed. The optimization model is constructed with the goal of minimum carbon emissions of power generation enterprises and minimum customer purchase cost of electricity, and the model is solved by using the Cplex solver. The optimized trading paradigm is compared with the conventional electric energy market trading paradigm, and the case analysis verifies that the optimization model corresponding to the trading paradigm in this article can well decline the carbon emission and customer purchase cost of electricity.

Aiming at the problems of poor working environment and low working efficiency of secondary cable manual threading, this paper proposes a design method of secondary cable auxiliary threading lead mechanism based on the principle of electromagnetic adsorption. Firstly, the principle of electromagnetic adsorption is analyzed, and the structure of traction end, threading end and electromagnetic adsorption are designed. Then, the finite element model of the adsorption device is constructed to analyze the relationship between the magnetic flux density in the inner and outer magnetic poles, the adsorption force and the air gap. The adsorption force of the designed adsorption device is determined to be 77.8N. Finally, the experimental platform is built to carry out related experimental studies such as primitive verification, repeatability and efficiency comparison. The experimental results show that the designed mechanism can work stably for about 12h, and the efficiency is increased by 87.99% compared with the manual threading method.

This paper aims to explore the application of isolation technology in high voltage design of energy storage systems (ESS), with a focus on analyzing the characteristics of optical isolation, magnetic isolation, and capacitive isolation technologies and their performance in different application scenarios. By combining technical comparison, application analysis, and case studies, this paper elaborates in detail on the application of isolation technology in improving system safety, reducing electromagnetic interference, achieving signal and energy transmission, and facilitating measurement and control in high voltage environments. The results indicate that reasonable selection of isolation technologies can effectively improve the safety and reliability of high voltage energy storage systems, providing theoretical basis and practical guidance for the design and optimization of high voltage energy storage systems.

In recent years, active phased array radar has imposed increasingly demanding requirements in aspects such as size, weight, and power density, presenting considerable challenges to the volume, power, and heat dissipation of the transmitter and receiver components. This paper proposes a thermal-electric co-design scheme for high density integrated transmitter and receiver components and designs a system in package with high efficiency heat dissipation, high output power, and high integration to achieve the transmitter and receiver front-end functions of the components which has been verified in the components.

Recursive Fourier algorithm is a commonly used digital signal processing algorithm for protection relays. Its characteristic is to use the last calculation result to calculate the current result. Its calculation efficiency is very high. However, the recursive algorithm has a memory effect. Errors caused by accidental factors will be kept and be difficult to detect, bringing hidden dangers to the operation of the protection device. In this paper, a fault-tolerant mechanism suitable for recursive algorithm is proposed to eliminate the memory effect and prevent irrecoverable calculation deviation caused by occasional or accumulated errors, thus effectively preventing such problems from causing misoperation or failure of protection devices.

In the context of “dual carbon” goal, integrated photovoltaic storage and charging station (IPSCS) can effectively solve the problem of independent operation of multiple types of flexible resources. To enhance the collaborative consumption capacity of source load and reduce carbon emissions, this paper proposes a multi-timescale day-ahead operation strategy for IPSCS that considers carbon emission stratification and source load interaction. Firstly, hybrid prediction model and Monte Carlo method are applied to historical data to derive typical photovoltaic output and electric vehicle load scenarios, respectively. Secondly, the objective function of the mathematical model of the operation strategy of the integrated station is minimum comprehensive planning cost, minimum carbon emission, and maximum utilization of new energy. The model is solved using an improved whale optimization algorithm (IWOA) incorporating an opposition-based learning strategy and diversity variation processing. Finally, the rationality and effectiveness of the proposed strategy are verified through case analysis.

Ultra-high voltage AC power system usually uses standard lightning current parameters to calculate external overvoltage, and lightning observation data show that more than 80% of the lightning process is multiple lightning strikes, which is significantly different from the standard recommended waveform. Under the background of frequent multiple lightning accidents in ultra-high voltage AC system, it is urgent to put forward a rigorous and scientific evaluation method of multiple lightning parameters. Therefore, this paper takes a 500kV AC ultra-high voltage transmission system as the object, and proposes a multiple lightning current waveform parameter evaluation method considering the transient characteristics of the line from the extreme lightning conditions and the actual fault recording. The analysis shows that the fault recording inversion method can characterize the real multiple lightning strikes. Extreme multiple lightning strikes method analyzes the lightning current parameters under harsh conditions from the lightning resistance level of the cable. The waveform parameter evaluation method proposed in this paper provides a technical scheme for overvoltage analysis of ultr-high voltage transmission system in lightning-prone areas.

To fully exert the advantages of the convolutional neural network (CNN) in image recognition and classification, a fault diagnosis method for four-quadrant pulse rectifiers based on CNN and Gramian angular difference field (GADF) is proposed. GADF is utilized to transform the one-dimensional time series of rectifier current into a two-dimensional feature map, preserving the temporal dependency of the data and identifying the temporal correlations of the signal over different time intervals. The CNN then extracts and classifies the features of open circuit faults in the rectifier from the generated feature maps. This method is compared with other common fault diagnosis methods. Simulation analysis results indicate that this proposed method achieves higher diagnostic accuracy compared to other fault diagnosis methods.

Compared to other primary equipments such as busbars, lines, and circuit breakers, transformers have a more complex structure and are the only equipment in the power system that connect different voltage levels. In addition, the influence of the Y/D transform makes the fault characteristics complex and variable, making it difficult to locate the fault point. The fault localization depends on the experience of the engineer. There is an urgent need for a complete automated fault location system. This article first classifies the possible situations that may cause transformer protection starting or tripping, and then sets fault localization criterion step by step. The criterion greatly enhances the automation level of transformer fault localization and has good engineering implementation value. The feasibility and accuracy of this method are proved through multiple sets of simulation waveforms.

In order to solve the problem of high redundancy and low positioning accuracy of traditional cable fault location spectrum data, this paper proposes a high precision cable fault location method based on chirp-Z transform (CZT). Firstly, according to the transmission line theory, the distribution parameters and reflection coefficient characteristics of the fault cable are analyzed. Then, CZT is performed on the real part of the reflection coefficient. Finally, iterative filtering is used to denoise and obtain the cable fault location spectrum. The results show that the fault point recognition error of the proposed method is 0.025%~0.275%. Compared with fast Fourier transform (FFT), the proposed method has the advantages of refined location spectrum, high resolution, low redundancy and high fault location accuracy.