Simulation of differential relay for transformer protection
2020-03-20,
Azizan N.S.,
Wooi Chin Leong,
Baharuddin Ismail,
Syahrun Nizam Md Arshad @ Hashim,
Isa M.,
Wan Azani Wan Mustafa,
Rohani MNK
In electric power system, transformers are an important element and their protection are critical. As the transformer might be damaged during a fault, faster and more selective protection was required. For this purpose, the design of differential protection was utilized. In this study, the differential relay simulation has been successfully done using MATLAB/Simulink. The essential approach is to protect the power transformer against internal faults and avoid interference in the power system. The evaluation has been accomplished at different fault conditions. Several types of faults including double line-to-ground, single line-to-ground and line-to-line faults are studied. Simulation studies were performed and the relays performance with different system parameters and conditions were investigated. The obtained results illustrated for the differential relay represents an appropriate action.
A Review: Partial Discharge Detection using UHF sensor on High Voltage Equipment
2020-01-07,
Roslizan N.D.,
Mohamad Nur Khairul Hafizi Rohani,
Wooi Chin Leong,
Isa M.,
Baharuddin Ismail,
Afifah Shuhada Rosmi,
Wan Azani Wan Mustafa
Partial discharge (PD) is one of the most popular failure or breakdown that can happen at high voltage (HV) equipment. PD is the fault that causes the insulation breakdown occurred between two electrodes. It happened or occurred because of the improper insulation, ageing, environment effect and manufacturing defects. The loss of the power will affect consumer and system operation. One of the technique that can measure or detect the PD is by using ultra high frequency (UHF) method for HV equipment insulation condition monitoring and assessment. In this paper, the application of UHF method have been reviewed as the best method to detect PD in transformer, GIS and cable. The UHF method for every electrical equipment is described in order to detect the PD and the laboratory result shows that this method can be considered as suitable technique. Based on this review, the new design in UHF sensor is required in order to improve the sensitivity and bandwidth for PD detection in HV equipment. The valuable parameter such as size and PD frequency range can be used for early stage of designing new the UHF sensor.