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The new power system puts forward higher requirements for the functionality, real-time performance and reliability of relay protection equipment. Therefore, this paper designs a monitoring platform for the operation of relay protection equipment at distribution network side under the background of new power system. The platform obtains the running state of relay protection equipment by establishing simulation models of different types of relay protection equipment on the distribution network side. The fault time, fault type and current action of relay protection equipment at distribution network side are analyzed to realize the monitoring of operation state. At the same time, the visual representation method of monitoring data based on three-dimensional parallel scattergram and human-computer interaction is adopted for human-computer interaction, and the electromechanical protection device is controlled to realize current quick-break protection and overcurrent protection. The experimental results show that the platform can effectively monitor the operation of relay protection equipment on the distribution network side in real time and accurately judge the action of the equipment, and the application effect is good. [ABSTRACT FROM AUTHOR]

Abstract The new power system puts forward higher requirements for the functionality, real-time performance and reliability of relay protection equipment. Therefore, this paper designs a monitoring platform for the operation of relay protection equipment at distribution network side under the background of new power system. The platform obtains the running state of relay protection equipment by establishing simulation models of different types of relay protection equipment on the distribution network side. The fault time, fault type and current action of relay protection equipment at distribution network side are analyzed to realize the monitoring of operation state. At the same time, the visual representation method of monitoring data based on three-dimensional parallel scattergram and human-computer interaction is adopted for human-computer interaction, and the electromechanical protection device is controlled to realize current quick-break protection and overcurrent protection. The experimental results show that the platform can effectively monitor the operation of relay protection equipment on the distribution network side in real time and accurately judge the action of the equipment, and the application effect is good.

With the rapid development of power grid, the structure and technology of the secondary system in substations are also constantly innovating. The new generation of intelligent substations has achieved online monitoring functions for secondary equipment, making some state variables of relay protection equipment become observable indicators. Based on this, this paper proposes a novel relay protection equipment status evaluation strategy. Firstly, considering the fuzziness and uncertainty of the boundary division of relay protection evaluation levels, a relay protection risk assessment method based on normal cloud model has been proposed. Then, due to the particularity of historical statistical data, a weight calculation method combining analytical hierarchy process (AHP) and entropy weight method is adopted to eliminate subjective factors in the weight calculation process. Meanwhile, the equipment operation risk level was determined by calculating the certainty of the corresponding evaluation level for each indicator. Finally, in case study, the proposed method is used to evaluate the status of relay protection equipment, and the feasibility and accuracy of this method are verified through the analysis of the results. [ABSTRACT FROM AUTHOR]

With the rapid development of power grid, the structure and technology of the secondary system in substations are also constantly innovating. The new generation of intelligent substations has achieved online monitoring functions for secondary equipment, making some state variables of relay protection equipment become observable indicators. Based on this, this paper proposes a novel relay protection equipment status evaluation strategy. Firstly, considering the fuzziness and uncertainty of the boundary division of relay protection evaluation levels, a relay protection risk assessment method based on normal cloud model has been proposed. Then, due to the particularity of historical statistical data, a weight calculation method combining analytical hierarchy process (AHP) and entropy weight method is adopted to eliminate subjective factors in the weight calculation process. Meanwhile, the equipment operation risk level was determined by calculating the certainty of the corresponding evaluation level for each indicator. Finally, in case study, the proposed method is used to evaluate the status of relay protection equipment, and the feasibility and accuracy of this method are verified through the analysis of the results.

Relay protection equipment (RPE) is a type of automation equipment aiming to protect power systems from further damage caused by local faults. It is thus important to ensure the normal operation of RPE. As the power density of electronic components continuously increases, the overheating problem of RPE cannot be neglected. Given the difficulties in implementing direct measurement and predicting development trends of RPE temperature, a novel hotspot temperature monitoring method for RPE was proposed, which is a data-driven method. The generative adversarial network, aided by a physical model, is used to address small samples. Afterwards, a stacked ensemble model established based on random forests was used to predict the hotspot temperature of the RPE. Experiment results show that the proposed method can effectively predict hotspot temperature of RPE with the predictive error lower than 2%. And comparative results demonstrate the superiority of the proposed method compared to other methods. [ABSTRACT FROM AUTHOR]

Effective thermal management measures are of great significance for improving the reliability of relay protection equipment. Firstly, the paper establishes a temperature calculation function for components based on the thermal superposition model, calculates the minimum heat dissipation distance between components, and converts the functional coordination of components into coordinate constraints. An optimised layout scheme for components is obtained quickly based on the minimum heat dissipation distance and coordinate constraints. The finite element simulation results show that the optimized layout significantly improves the temperature of the components, with a maximum temperature reduction of 8.6%. Then a component overheating warning strategy is proposed based on state recognition. The life-accelerated decay ratio of the components is calculated by monitoring the operating temperature, and the allowable operating time and alarm signal of the components at a specific temperature are combined to reflect the components’ status accurately.

Since there are no monitoring devices in relay protection equipment of substations, it takes up a lot of manpower and material resources in operation and maintenance (O&M), and the efficiency is very low. In this paper, we solve the giving fault prediction model by applying particle swarm optimization algorithm and support vector machine algorithm for relay protection equipment. The combined model was found to be able to establish the correlation between the variables more accurately and improve the prediction accuracy of the model by comparison. The simulation result shows that the prediction accuracy of the model is at least 91% for three different devices. The combined prediction model can not only provide strong technical support for the maintenance strategy of relay protection equipment but also improve the maintenance efficiency and reduce the failure rate of protection equipment. [ABSTRACT FROM AUTHOR]

Relay protection equipment is important to ensure the safe and stable operation of power systems. The risks should be evaluated, which are caused by the failure of relay protection. At present, the fault data and the fault status monitoring information are used to evaluate the failure risks of relay protection. However, there is a lack of attention to the information value of monitoring information in the normal operation condition. In order to comprehensively improve monitoring information accuracy and reduce, a generalized proportional hazard model (GPHM) is established to fully exploit the whole monitoring condition information during the whole operation process, not just the monitoring fault condition data, with the maximum likelihood estimation (MLE) used to estimate the parameters of the GPHM. For solving the nonlinear equation in the process of parameter estimations, the adaptive homotopy algorithm is adopted, which could ensure the reversibility of the Jacobi matrix. Three testing cases have been reviewed, to demonstrate that the adaptive homotopy algorithm is better than traditional algorithms, such as the Newton homotopy algorithm, regarding the calculation speed and convergence. Therefore, GPHM could not only reflect the real time state of the equipment, but also provide a sound theoretical basis for the selection of equipment maintenance types. [ABSTRACT FROM AUTHOR]