Leakage Current Monitoring System Research Articles

An energy and leakage current monitoring system for abnormality detection in electrical appliances

Unsafe electrical appliances can be hazardous to humans and can cause electrical fires if not monitored, analyzed, and controlled. The purpose of this study is to monitor the system’s condition, including the electrical properties of the appliances, and to diagnose fault conditions without deploying sensors on individual appliances and analyzing individual sensor data. Using historical data and an acceptable range of normal and leakage currents, we proposed a hybrid model based on multiclass support vector machines (MSVM) integrated with a rule-based classifier (RBC) to determine the changes in leakage currents caused by installed devices at a certain moment. For this, we developed a sensor-based monitoring device with long-range communication to store real-time data in a cloud database. In the modeling process, RBC algorithm is used to diagnose the constructed device fault and overcurrent fault where MSVM is applied for detecting leakage current fault. To conduct an operational field test, the developed device was integrated into some houses. The results demonstrate the effectiveness of the proposed system in terms of electrical safety monitoring and detection. All the collected data were stored in a structured database that could be remotely accessed through the Internet.

A Labview Based Leakage Current Monitoring System For HV Insulators

A Labview Based Leakage Current Monitoring System For HV Insulators

The Analysis in Several Application Issues for Leakage Current Electrical Fire Monitoring System

This paper starts with an introduction into the current situation of electical fires and the development of electrical fire monitoring systems. Then the paper summarizes some main issues of leakage current electric fire monitor system of engineering application. In order to improve product quality, the necessity of carrying out some tests is dicussed in this paper, too, such as the product feature extension, EMC tests, super-current shock test, balance test and the transformer function test. Nest, the paper proposes some ideas on the standardization of electric fire prevention and the improvement of management policy. Finally, a few suggestions for the sound development of electric fire prevention application are provided.

Computer–Based Monitoring System for Analysing Surface Leakage Current in an IEC 587 Test Set–Up

Surface discharge is a common electrical discharge that normally occurs on outdoor insulators under wet and contaminated conditions. The dry–band discharge exists because of the leakage current that flows on the insulator surface. Measuring the surface leakage current can identify the performance of insulating materials as well as the characteristics of discharges. A computer–based on–line monitoring of surface leakage current is found to be more practical due to the long period of time taken in conducting the laboratory test. This paper describes the design and development of a leakage current monitoring system associated with surface tracking and erosion resistance test set–up of IEC 587. The LabVIEW software package is used to develop a measurement program for recording and analysing leakage current signals. Experimental works have shown the capability of the developed system in detecting the performance of insulating materials as well as identifying the characteristics of the surface discharges. Besides the on–line monitoring function, a data storage feature is also added to the system to allow for further analysis. Key words: surface discharge; leakage current; signal analysis; virtual instrument program

Leakage Current and Discharge Phenomenon of Outdoor Insulators

This paper descirbes leakage current characters and discharge phenomenon of outdoor insulators both in the lab and in the field. The results are hoped to be used for online monitoring of the contamination levels. The following contents are introduced in the paper: leakage current monitoring systems, relationships between leakage current and discharge phenomenon, flashover prediction methods and its applications in the field. The leakage current monitoring system is introduced firstly. Then the relationships between leakage current and discharge phenomenon for both suspension insulators and post insulators are presented based on the laboratory tests. A new parameter (I * ) that accounted for maximum leakage current (Ih) and different insulator shapes is introduced to estimate the flashover voltage for different kinds of pollutant layers when they are saturated with moisture. Meanwhile, the relationships between relative humdity (RH) and maximum leakage curren, altitude and maximum leakage current are investigated. With these results a flashover prediction method is developed. Ih measured in different relative humidity is converted to I * for the same contaminate layer when it is saturated with moisture. Then the flashover voltage is estimated by I * . Furthermore, an online leakage current monitoring results are analyzed. The relationships between leakage current characters in the field and ambient relative humidity are analyzed. The results show that although there are some differences between the leakage current in the field and in the lab because of some especially serve atmospheric conditions, the relationships are similar. Meanwhile, leakage current waveforms in different weather conditions are investigated. The waveforms of leakage current in the field are similar with those in the lab. The leakage current waveform that accounted for strong arc is found in the field. Finally, the contamination level of the field insulator is evaluated. The results corresponds well with the local condition.

A New Broadband Microcurrent Transducer for Insulator Leakage Current Monitoring System

In this paper, a type of high bandwidth microcurrent transducer designed for online monitoring of an insulator is described. According to the equivalent circuit model, the effects of transducer winding number, stray capacitance, and loading resistance on passbandwidth and sensitivity are discussed. The academic lower limit of the transducer is nearly zero and the upper limit is infinity, which are proven by the analysis of the electronic circuit and the simulation by saber. The test of the current transducer shows that the transducer can be used in most high-voltage insulations systems with broad passbandwidth, high linearity, high sensitivity, and noncontact.

A new on-line leakage current monitoring system of ZnO surge arresters

This paper presents a new on-line leakage current monitoring system of zinc oxide (ZnO) surge arresters. To effectively diagnose the deterioration of ZnO surge arresters, a new algorithm and on-line leakage current detection device, which uses the time-delay addition method, for discriminating the resistive and capacitive currents was developed to use in the aging test and durability evaluation for ZnO arrester blocks. A computer-based measurement system of the resistive leakage current, the on-line monitoring device can detect accurately the leakage currents flowing through ZnO surge arresters for power frequency ac applied voltages. The proposed on-line leakage current monitoring device of ZnO surge arresters is more highly sensitive and gives more linear response than the existing devices using the detection method of the third harmonic leakage currents. Therefore, the proposed leakage current monitoring device can be useful for predicting the defects and performance deterioration of ZnO surge arresters in power system applications.