Failure Of Switchgear Research Articles

Detecting surface discharge faults in switchgear by using hybrid model

<span>Switchgear plays a crucial role in power systems, providing protection and control over electrical equipment. However, tracking (surface discharge) can lead to insulation degradation and switchgear failure, necessitating reliable and effective identification of tracking defects. In this paper, we propose a hybrid one-dimension convolutional neural network long short-term memory networks (1D-CNN-LSTM) model as a solution to this problem. Data from both time domain analysis (TDA) and frequency domain analysis (FDA) are utilized for model evaluation. The model achieved error-free accuracy of 100% in both TDA and FDA during the training, validation, and testing phases. The model's performance is further assessed using performance measures and the visualization of accuracy and loss curves. The results show that the hybrid 1D-CNN-LSTM model works well to accurately find and classify surface discharge tracking defects in switchgear. The model offers precise and dependable fault identification, which has the potential to significantly enhance switchgear functionality. By enabling proactive maintenance and timely intervention, the proposed model contributes to the overall reliability and performance of switchgear in power systems. The findings of this research provide valuable insights for the design and implementation of advanced fault detection systems in switchgear applications.</span>

Explore the verification and improvement method of insulation of 10~35kV high voltage switchgear

In the rapid development of China’s power system, the number of applications of high-voltage switchgear is increasing. Every year, tens of thousands of switchgear are put into the power industry. Since the performance and quality of high-voltage switchgear directly determines the operation efficiency of the system and has a positive impact on the safety production and effective power supply of the power grid system, scholars from all over the world have gradually strengthened the research on the insulation failure of switchgear and conducted verification and analysis based on practical cases. In this paper, based on the understanding of the development status and fault research technology of 10-35kV high voltage switchgear, according to representative insulation accident cases, taking the high voltage switchgear in a certain area as an example to verify and analyze, and finally put forward effective improvement methods.

Evaluation and optimization of electric field on a high-voltage switchgear in nuclear power station

Safety of electric power systems depends heavily on distribution of electric field in high-voltage switchgear. Switchgear failure can lead to fatal disasters in important systems. It is necessary to evaluate electric field and insulation performance for high-voltage switchgear in key systems. In this paper, considering a high-voltage switchgear system designed for nuclear power station, a three-dimensional finite element model is developed for the whole system. Distribution of electric field is simulated under different loads, including the specified voltage and the overload. The insulation property of the switchgear system is then evaluated. Experiment on the physical prototype validates the simulation evaluation. To make the electrical field well distributed and reduce peak value, method of orthogonal experiment is used for parameter design. Optimization and improvement are then proposed. The optimization results show that the reliability is improved and the electric field is well distributed. The numerical model is established on personal computer, while it is solved remotely on High Performance Computing Center. Corresponding modeling techniques and computing methods are provided in this paper.

Study on Determination of SF6 Decomposition Based on Gas Chromatography

The current research about SF6 switchgear failures mainly focuses on various troubleshooting methods, while ignoring the impact of SF6 gas decomposition products on equipment and the types of failures they reflect, and the application of SF6 gas decomposition products to diagnose equipment failures still needs to be further explored and improved. Therefore, this paper focuses on the study of the decomposition process of SF6 under partial discharge failure, and conducts theoretical analysis of the decomposition product composition of SF6 under partial discharge failure, and detects SF6 gas decomposition products by gas chromatography. Finally, it can be concluded that when the concentration of S2F10 and S2OF10 is about 5μL/L, the switchgear is likely to have a partial discharge failure. At this time, the maintenance personnel should deal with it in time to ensure that the switchgear can be put into use normally.

Reliability model for switchgear failure analysis applied to ageing

AbstractThe failure analysis for each component is the biggest problem for maintenance task for switchgears. It should consider the redundant mechanical and electrical systems, in circuit breakers for the analysis. In recently researches, they are often described innumerable system failure modes, according to the methodology applied: RCM plus, RCM 2, among others. Nevertheless, in these methodologies, the specific effects are independently considered (for example the IEEE standard) has proposed 11 failures modes, furthermore CIGRE has proposed 4 evolutionary failures modes however The effects are independent for the failure mode, there is no interaction between them. On the other hand, this research proposes a new perspective with combinations between them and the degradation sequence for ageing process. A proficient method is used to recognize main failure modes, according to IEC 62271–100 (2011) and IEC 62271-1 (2007), later, in the space of arbitrary components, it accomplishes system reliability analysis to calculate the system failure probability, due to reliability analysis, this research proposes a new proposal to complement the IEC standards. To establish the main failure and to propose in decreasing in order their influence. This new proposal to model the searching technique uses the Weibull and gamma distribution. Finally, the authors have done a case study with the new proposal, to prove the reliability goal for contending failure modes under the faster circumstances than traditional methods. In the section 1, the main aspect for the failure analysis in switchgear is described, in the section 2 a system reliability is analyzed with the failure modes criteria: A classical approach and a reliability scope in the analysis. In the section 3 a new proposal is described for a framework, it considers the failure mode analysis and reliability studies, later, in the section 4, the case study is developed with thirty-four hydraulic switchgear and 3201 site acceptance test for preventive maintenance and a section 5, for a discussion about the new proposal in the international standards.

Modular online monitoring system to allow condition-based maintenance for medium voltage switchgear

Nowadays, the concern to have a better maintenance strategy of an electrification system is being one of the key results of online monitoring and diagnostic approach. This study illustrates a new modular solution for online condition monitoring in order to implement condition-based maintenance for medium voltage (MV) switchgears and breakers. The solution can predict potential failures allowing maintenance scheduling in advance by applying dedicated sensing technologies. Circuit breaker failure modes regard, for instance, open and close commands malfunction, charging mechanism malfunction, current interruption issues (contact wear), and overheating. Switchgear failure modes regard mainly insulation deterioration and loose connections. The online monitoring and diagnostic solution can detect in advance the mentioned failure modes by means of specific sensors pluggable whenever required on new or existing switchgears. Innovative algorithms process all the information provided by sensors, to provide health indication for each component and failure mode. Moreover, an overall health index of the monitored equipment is calculated and represented by a traffic light. The red, yellow, and green colours indication with corresponding alert messages gives indication on predictive maintenance planning. The solution allows savings on maintenance costs (OPEX), asset lifetime extension (CAPEX), as well as prediction on failure (outages liabilities).

Research on Monitoring System of Environment in Switchgear

When high voltage electrical equipment running in electrical transformer station, heating, electrical accident would be caused by some factors, for example, the temperature of switch node higher then alarm, discharge with high humidity, condensation of electrical equipment. Therefore, the implementation on-line monitoring for high voltage electrical equipment has become the important problem needed to solve. This paper analyzes the effect of node temperature and the humidity in the switchgear failure, and designs temperature/humidity environment monitoring terminal with low power controller and integrated temperature/humidity sensor. The RS485 interface is used as the communication channel to exchange information with monitor server. In monitor computer, a server is working to collect real time environment information from each terminal and provides web service for user in internet. Experimental results show that this system can realize the contact temperature and humidity environment online monitoring, display, alarm and other functions, and has good scalability and maintainability.

The effect of switching surges on 34.5 kV system design and equipment

High failure rates of equipment resulting in severe operational problems caused the Colorado Springs Dept. of Utilities to investigate switching surge phenomena on their 34.5 kV distribution system. Digital simulations were performed to quantify the magnitude of overvoltages created by such operations as cable switching, capacitor bank switching, and switch restrike in an effort to identify the causes of padmount switchgear failures on the underground portions of the system. Results of the study indicated that certain system design changes could be made which would greatly alleviate the severity of the switching surge environment found on the system. The application of arresters was investigated in an effort to further reduce the impact of these transients. Results of field tests and digital simulations confirmed the need for increased BIL levels in switchgear being purchased for this system voltage. >

A High-Power Oilless Circuit Interrupter Using Water

The oil circuit breaker has been for many years the standard type of circuit interrupter for heavy-duty powerhouse service. Since the introduction of modern arc-rupturing devices into these circuit breakers, the occurrence of serious trouble attributable directly to oil switch-gear failure has been rare. However, the appearance on the market of various types of oilless circuit breakers of considerable interrupting capacity has encouraged the idea that the complete elimination of oil in power house switchgear may be both desirable and practicable. Further experimental investigation and development activity on the part of switchgear manufacturers seems to indicate that currents of 60,000 amperes or more at 13,200 volts can be interrupted satisfactorily in circuit breakers using either air or water as the arc-quenching medium. This paper describes the construction and operating characteristics of a high-power water circuit breaker.