Breaker Failure Research Articles

Optimal circuit breaker allocation strategy in DC transmission-connected systems

The purpose of this study is to provide data for the best possible circuit breaker allocation in power grids with HVDC transmission while taking circuit breaker failure into account. The lack of a suitable selection of HVDC circuit breakers is one of the primary obstacles to establishing an appropriate protection system for HVDC transmission. This research focuses on finding the optimal circuit breaker allocation strategy with respect to the transient response of the system, especially when the grid operator is using existing circuit breakers, rather than on the necessary steps to improve the technology of circuit breakers. Case studies are simulated using PSCAD/EMTDC in order to verify the transient response of the transmission system corresponding to the allocation of circuit breakers and the circumstance of circuit breaker failure. It is crucial to remember that there isn’t a strategy that is always the best. Consequently, a detailed analysis of the suggested approach is required, taking into account the benefits and drawbacks from the standpoints of fault clearing, power system planning, and operational factors. In the context of HVDC transmission, the authors hope that their research will spark and start conversations about circuit breaker allocation strategies.

An efficient hydrogen-based water-power strategy to alleviate the number of transmission switching within smart grid

The main advantage of Transmission Switching (TS) is decreasing the cost function in a power system. Using TS requires a high number of transmission switching in the system, which can cause some problems in the long run. These problems include decreased lifetime and failure of circuit breakers (CBs), higher repair and maintenance costs, line outage, increased probability of load shedding, and lower reliability of the system. In this paper, congestion management is utilized in the unit commitment problem constrained to the security with the TS to decrease the number of switching. This methodology will resolve the mentioned problems and improve the overall security of the system. Besides, a grid-connected water-power package is suggested to make relaxation for the line congestion which results in the alleviation of the transmission switching. The proposed water-power system is restructured regarding the fuel cell based renewable resource considering the hydrogen tank. Indeed, such a restructured system utilizes the water grid to generate the hydrogen and then power with the aim of linking the electrical grid. Also, on the account of being uncertain of some parameters coming in the electrical grid, an uncertainty-based UT function is addressed to handle uncertainty impacts on the grid's performance. To make awareness-raising, we carry out an outage of the generators as a different contingency scenario of the problem. Finally, the introduced model is testified on two 6-bus and 118-bus grids and solved by Bender's decomposition method. The simulations are performed in GAMS software to confirm the introduced approach effectiveness. Inferred from the results that the proposed strategy can help the grid operator lessen the line congestion up to an acceptable level.

APLICAÇÃO DA LOGICA FUZZY PARA PRIORIZAÇÃO DA MANUTENÇÃO DE DISJUNTORES DE SUBESTAÇÃO DE ENERCIA ELÉTRICA

In electric power supply, in order for electric power substations to continue to operate, the maintenance of the electrical equipment present is of utmost importance. Currently there are several forms of preventive maintenance scheduling, where each power supply company adopts an existing method or develops a new method. To perform this work, we used the methodology of fuzzy logic that enables the calculation of reliability among the uncertainties, in order to classify the degree of criticality in the maintenance of circuit breakers that may present technical problems, performed a preventive maintenance, comparing with the method already used by the distribution company. The results found demonstrate greater accuracy than the model currently presented by the distributor. Although the results obtained are satisfactory, its use is only indicated as a support tool for teams and specialists. Since its factors still need to be adjusted, for a better predictability rate, where some samples the maintenance date is very close to the breaker failure date.

The problem of the actual insulation coordination for 500 kV with overvoltage in substations and the needed for more surge arresters in high voltage grid

The new extra high voltage overhead lines and substations have increased the overvoltage phenomenon in the electrical interconnected system, especially in high voltage circuit breakers operate in a failure condition. This research develops a new methodology for transitory analysis, due to limits in the insulation coordination, available in the international standards IEC 60071, however it is not enough, more surge arresters should be required with the new overhead lines caused by overvoltage. The influence by lightning, circuit breaker failure (50BF), grounding system, towers and insulation chains are affected, in three-phase reclosing, maneuvers and transformer energization, finally a new assessment of the performance develops an accurate calculation of the overvoltage. Our findings are in the three-phase reclosing, the maneuvers have introduced overvoltage through the transmission line, higher values ​than 2.3625p.u. However, the insulation coordination is less than 2.32p.u.; compared with the limit of 2.28p.u. Finally, the overvoltage has increased from 160% to 258% according to the distance in the overhead line in 500 kV, with the needed of surge arresters, with the new equipment the overvoltage has decreased from 258% to 100%.

The modular design and verification of a 110kV circuit breaker

The reliability of circuit breakers is of great importance for the safe operation of the power grid. Most failures of the circuit breakers were caused by their operating mechanism, which often contains a lot of components. What is more, the secondary connections of the circuit breakers are also complicated. The lack of modular design of domestic circuit breakers now limits the development of reconditioning. To improve the reliability and reduce the maintenance time of the circuit breaker, research on the modular design of a 110 kV circuit breaker has been carried out and the verification was also conducted.

Transient overvoltage transfer and amplification in a 400 kV network – A case study

The paper investigates overvoltage propagation in a 400 kV network within the National Grid Electricity Transmission system in the UK. The studies were triggered by a replacement project for two parallel 400 kV cables and the installation of an additional one. The network in the vicinity of the cables has historical issues of flashover and circuit breaker failures. Electromagnetic transient studies were performed to simulate energisation and fault inception and clearance for the three new cables to examine compliance against overvoltage standards and limits. Studies were performed using the DIgSILENT analysis tool. Studies show that due to resonance in a specific frequency range, switching overvoltage propagated and amplified at remote nodes to a level close to the equipment's rated switching voltage. As mitigation, surge arresters with characteristics different from the National Grid recommended surge arresters were proposed and found suitable to bring the overvoltage values within the design limits for temporary overvoltage.

Research on circuit breaker failure protection and the secondary accelerated fault isolation scheme of VSC-HVDC grids

When the direct current circuit breaker (DCCB) fails to operate, the fault range will further expand, endangering the safe operation of the power gird. Therefore, this study proposes a DCCB failure protection method and a secondary accelerated fault isolation scheme of voltage source converter-based high-voltage direct current (VSC-HVDC) grids. On the basis of considering the influence of DCCB disconnection, characteristics of fault current after the failure of the DCCB are analyzed, and a circuit breaker failure protection method based on “increase current” discrimination is proposed. By analyzing the logical relationship among failed breaker re-tripping, adjacent DCCB action, blocking of the converter station, and AC circuit breaker action, a secondary accelerated fault isolation scheme is proposed to minimize the fault isolation area. The scheme achieves the accelerated isolation of DC faults after the failure of the DCCB and avoids the trip of the AC circuit breaker effectively. Simulation results verify the effectiveness of the proposed scheme.

Motor Control Center Breaker Modification Through On/Off Switch to Prevent Motor Failure

Motor Control Center (MCC) GT module, is a power breaker device that connects the voltage source to the load. MCC breaker rack-in and rack-out activities can be classified as unsafe action and unsade condition. Because there is a possibility of explosion. As it had happened several times in several places in the world. In 2021 there were 3 force derating and force outages which are caused by MCC motor breaker failures. That accident resulted 500,516.67 KWh loss or Rp 682,262,223,- ($ 44,766). Therefore, modifications need to be made to 0.4kV MCC breaker by adding a selector for the order off blocker to minimize socket damage due to frequent rack-in-rack-out breakers activity. After installing the modification to all breakers in Priok POMU, there was no failures occurred. The frequency of rack-in-rack-out activities were reduced significantly and that is a good result for operation safety. This modification can also prevent Priok POMU from a potential loss and potentially increase net profit up to Rp 221,549,398,- ($ 14,537).

Deep auto-encoder network for mechanical fault diagnosis of high-voltage circuit breaker operating mechanism

Abstract To improve the accuracy of the mechanical fault diagnosis of the operating mechanism and fully exploit the characteristic information in the vibration signal of the high-voltage circuit breaker, a mechanical fault diagnosis method of the operating mechanism of the high-voltage circuit breaker based on the deep self-encoding network is proposed. First, the vibration signal of the switch operating mechanism is extracted, the wavelet packet conversion is performed, and the vibration signal of each frequency band is divided into equal times. The energy of the time–frequency subplane of the vibration signal is then calculated, and the time–frequency energy distribution is used as a switch. Finally, a breaker failure diagnostic model based on the deep self-coding network is established. Pretraining and tuning and a 126 kV high-voltage switch are used to simulate different types of faults and validate the method. Experimental results show that this method can acquire sample failure data and perform failure diagnosis, and the diagnosis accuracy rate reaches 97.5%. The deep self-coding network can fully pierce deep information on the switch vibration signal.

FUZZY MODELING OF SWITCHING EQUIPMENT FOR TASKS OF ASSESSING THE RISK OF EMERGENCY SITUATIONS IN THE EPS IN CASE OF ELECTRICAL EQUIPMENT FAILURES

Today in the electric power industry of Ukraine the issue of assessing the risk of EPS operation due to failures of electrical equipment is particularly important. Failures are associated with significant level of aging and low replacement rates of electrical equipment, also with the possible simultaneous emergency decommissioning of several elements as a result of terrorist attacks.
 Based on the analysis of the operating conditions of high-voltage switching equipment, standards and operational documentation method of diagnosing the technical condition of SF6 circuit breakers is proposed. This method is based on the use of fuzzy set theory.
 To assess the risk of power outages in the EPS in case of electrical equipment failures, a linguistic model is proposed for determining the total residual life and the probability of failure of SF6 high-voltage circuit breakers of various types. Which is based on the aggregation of information on the technical condition of individual functional units.
 An approach is proposed to take into account the importance of individual units of the circuit breaker in terms of the impact on the total residual life by weight coefficients determined due to failure statistics. The result of determining the total residual life is the ability to estimate the probability of failure on the observation time interval.
 Tuning and adaptation of the developed linguistic model of the SF6 circuit breaker to real operating conditions is provided by adjusting the parameters of the membership functions of the terms of the input linguistic variables using weighting coefficients and fuzzy inference with weighted average truth.
 The developed linguistic mathematical model for assessing the technical condition and probability of failure of SF6 circuit breakers can be used as a component of the complex of risk analysis programs in the EPS. And the formation of preventive actions to ensure the operational reliability of electrical equipment and regime reliability of the EPS in case of emergency equipment failures.

Circuit Breaker Identification Based on SSD

The circuit breaker is a device that cuts off and connects the load circuit in the power system, cuts off the fault circuit, prevents the accident from expanding, and ensures safe operation. Detecting circuit breaker failures is necessary to ensure power systems’ safety. Before fault identification, the circuit breaker must be identified and positioned first. In this paper, a circuit breaker identification technology based on SSD is adopted, and SSD is used to identify the circuit breaker and mark the voltage name quickly.

A Coordinated Multi-Element Current Differential Protection Scheme for Active Distribution Systems

This paper introduces a current differential protection scheme, appropriate for application in medium voltage active distribution systems, where it is desired to keep the greatest possible number of loads and DG units energized during a fault. Conventional two-terminal percentage current differential relays are used to form successive, time-current-coordinated, differential protection zones. Multiple time-delayed differential elements in each protection zone guarantee coordination with the zone's lateral protection devices, as well as between successive differential protection zones. Sensitive time-delayed differential elements protect against relatively high-resistance faults, while instantaneous differential elements minimize protection speed whenever possible. Additional emergency differential elements deal with post-fault topology changes and breaker failure conditions enhancing the overall scheme's performance. The proposed scheme is applied to a model of real medium voltage distribution system with distributed generation, considering a ring topology operation. A detailed simulation-based study proves the applicability and enhanced performance of the proposed scheme.

A Novel Fault Isolation Scheme in Power System With Dynamic Topology Using Wide-Area Information

The flexible and dynamic operation condition of the power system requires that the fault isolation scheme has sufficient adaptability. A novel fault isolation scheme based on wide-area information is proposed in this article. Based on graph theory, the adjacency matrices of the electrical components and circuit breakers are constructed. The real-time switch status data is exploited to reflect the dynamic changes of the network topology. Then, the tripping path of the circuit breaker connecting each protected electrical component is searched by the Floyd–Warshall algorithm to formulate the fault isolation set for all protected electrical components. The proposed approach is applied to fault isolation from a wide-area perspective, and it is not affected by system coordination and selectivity compared with the one based on local information. The effectiveness of the proposed scheme is verified on a power system with the typical electrical connection under the cases of a single fault, multiple faults, circuit breaker failure, and substation with the outage of dc power supply, and the case where the circuit breakers cannot trip. Since the tripping sequence of the circuit breakers is determined before the fault occurs, even with dynamic changes of the power system conditions, the proposed scheme can minimize the fault isolation zone with low fault clearance time.

Improved generator circuit breaker failure protection method combined with voltage quantities

Safe and reliable generator circuit breaker (GCB) failure protection can ensure effective isolation between generator and system under different fault conditions to avoid generator damage. In this paper, aiming at the existing problems of the GCB failure protection criterions based on current quantities, the voltage quantities are combined to constitute the improved GCB failure protection. Through fault sequence network analysis, it is concluded that there are voltage phasor differences between the two sides of GCB for the normally separated phases, while the values are zero for the rejected phases. On this basis, a GCB failure protection criterion based on the voltage phasor difference is proposed for the generators equipped with PTs at the two sides of GCB. After a generator fault occurs, in the process of de-excitation, the terminal voltage drops quickly except GCB three-phase rejection because of the voltage support from the system side. Moreover, under the GCB three-phase rejection situation, the loads cannot be effectively shed and no terminal voltage increase is caused compared with other GCB operation situations. Thus, the protection criterions based on the voltage variation are proposed to distinguish GCB three-phase rejection situation, including the voltage changing rate criterion and the increased voltage mutation criterion. They are used for generators equipped with only one terminal PT. Simulation results of PSCAD/EMTDC verify the effectiveness of the proposed methods.

Transient stability risk assessment framework incorporating circuit breaker failure and severe weather

ABSTRACT Due to the rising uncertainties in the power system and the need to develop a competitive electricity market, the risk of transient stability is an important issue to address. The traditional deterministic methods of transient stability assessment fail to consider the uncertain nature of input variables. Moreover, there is a dire requirement to incorporate the impact of circuit breaker failure and severe weather in the transient stability risk assessment procedure. Majority of transient stability risk research assumes that the circuit breaker will always trip upon fault detection; however, in practice, the circuit breaker may not operate due to internal fault. Thus, this paper proposes a transient stability risk assessment framework,incorporating circuit breaker failure and severe weather. It considers the impact of severe weather, in the form of wind storms. The concept of fragility curves is used to model this impact. The IEEE 14-bus and the IEEE 39-bus test systems were used to test and validate the effectiveness of the proposed approach. DIgSILENT PowerFactory was utilised for time-domain simulations for transient stability risk evaluation. The results show that it is vital to consider the circuit breaker failure and severe weather in the transient stability risk assessment procedure.

An additional bus inductance-based protection scheme for shipboard DC zonal electric distribution systems

The shipboard DC zonal electric distribution system (DC ZEDS) has seen a recent explosion of interest for its high reliability and strong survivability. With multiple sources and zones, however, the complicated structure brings challenges to its protection design, in which the breaker coordination is one of the key issues. In this regard, this paper proposes a protection scheme based on the additional bus inductance (ABI) for the shipboard DC ZEDS, which meets the requirements on speed, selectivity and reliability in shipboard protection. The breaker configuration is analyzed based on the structure characteristics of DC ZEDS, and the breaker coordination is addressed from transverse and longitudinal directions. The ABI assists shipboard protection in identifying faults in different zones, improving operation speed and lessening fault severity. A reasonable simulation model has been built, in which breaker failures and different operation modes are considered. Simulation results are shown to verify the effectiveness and applicability of the proposed protection scheme. The sizing of the ABI is discussed in the paper to provide theoretical basis for engineering practice.

A Breaker Failure Detection Method Based on Nonlinear Parameter Estimation for Modular Hybrid DC Circuit Breakers

Modular hybrid dc circuit breakers (DCCBs) have been widely employed to protect multiterminal high-voltage dc (MT-HVdc) grids. However, breaker failures still pose a challenge to the protection of MT-HVdc grids, especially for a single module failure of breakers. To this end, a breaker failure detection method based on nonlinear parameter estimation is presented. This proposed method consists of three parts. The first is a signal preprocessing method that eliminates the effect of the RC circuit of the hybrid DCCB. The second is an offline optimal parameter acquisition method that has an improved numerical model of the metal–oxide varistor (MOV) and combines the Levenberg–Marquardt (LM) algorithm with the particle swarm optimization (PSO) algorithm. The third is an online breaker voltage error calculation that estimates the breaker voltage based on the improved numerical MOV model to detect the partial failure of the modular hybrid DCCB. The performance of the proposed algorithm is evaluated by both power system computer aided design (PSCAD)/electro-magnetic transient design and control (EMTDC) tests and field tests. The study results prove the effectiveness of the proposed method for the partial failure of the modular hybrid DCCB considering different faulty conditions and the aging of MOVs.

Hardware in the Loop Testing of Main and Backup Protection Scheme for Systems with High Penetration of Inverter-Based Resources

Several challenges arise when designing an adequate protection scheme for transmission systems with inverter-based resources. The communication network plays a vital role in help- ing the protective relays to overcome the complexities of the archi- tecture and provide a suitable protection technique. This paper presents a co-simulation platform linking the simulated model of the modified IEEE 14 bus transmission system simulated on the RTDS simulator and the commercial SEL-421 protective relays to protect the system. The protection scheme utilizes voltage signals from the buses to identify the faulted section and determine the fault type. Voltages and currents are communicated to the relays by sending SV messages from RTDS to the relays using the GTNETx2 interface, synchronized by the GTSYNC interface card and SEL-2488 Satellite-Synchronized Network Clock. Several cases were simulated to investigate the protection system under breaker and relay failures to provide a suitable backup solution and allow the healthy feeders to serve the system during abnormal conditions. The real-time results show the capability of the sug- gested protection scheme.

Оценка надежности выключателей в схемах распределительных устройств с различной топологией

The article discusses issues related to assessing the reliability of high-voltage circuit breakers in switchgear schemes with different topology of their design. A generalized formula is presented, using which it is possible to carry out calculations and further assessment of the failure flow parameter versus the switchgear scheme in which the circuit breaker is installed. To identify topological features, the standard switchgear schemes presented in the regulatory documents are analyzed. Five main types of circuit topologies and types of circuit breakers have been identified depending on the type of switched connections. For carrying out comparative calculations, one typical option was selected for each type of circuit topology. The distribution of circuit breakers by types in these schemes is presented. Calculations of the circuit breaker failure rates in schemes with the same initial data and with breaking down by types are carried out. Conclusions on the extent to which various types of schemes influence the reliability of high-voltage circuit breakers both as a whole and separately, depending on the type of switched connection are presented.

Failure analysis of motorcycle shock breakers

AbstractThe shock breaker is one of the most important parts of a motorcycle, which functions as a vibration damper. This study aims to analyze the causes of motorcycle shock breaker failure. The research method used is comprised of visual observation, chemical composition testing, Vickers hardness testing, scanning electron microscopy-energy dispersive X-ray spectroscopy analysis, and tensile testing of a damaged shock breaker. From visual observation, it is found that the damage can be classified as a fatigue fracture, forming a damage pattern at 45°. The chemical composition testing results of the shock breaker fractures show that the material includes low-carbon alloy steel (of ST42 series) with a carbon content of 0.162%. The average hardness value of the damaged part of the shock breaker was increased to 204.87 HV, compared with 171.02 HV in areas far from the damage. The difference in hardness in the shock breaker was caused by the high stress acting on the shock breaker and the consequent strain hardening. The results of this study indicate that the failure mechanism of the motorcycle shock breaker was a functional failure due to errors in the shock breaker manufacturing process and fatigue.