A PC based ground impedance measurement instrument

Abstract

This paper presents a PC based instrument for ground impedance measurements. The instrument injects a transient electric current between the ground under measurement and an auxiliary ground, and it measures ground potential differences (GPDs) around the ground under measurement. The GPD measurements are processed with software which rejects external noise using correlation methods. Subsequently, estimation methods are used to extract the ground potential rise and ground impedance. The final result is the ground impedance versus frequency in a user selected frequency range. The instrument has been constructed and field tested by three utilities.

An application of maintaining constant grounding resistance of renewable energy sources by using a dspic

“…[5][6][7][8][11][12][13][14][15][16][17][18][19][20][21]. In this study, a method is developed to measure, analyze and observe the grounding resistance continuously.…”

An oscilloscope method for eliminating the interference and disturbance voltages for the earthing measurements of large earthing systems in substations

“…For performance measurements on the earthing systems, presented in [5][6][7] and also in [19], a special meter is required, such as the SGM. The methods are based on additional measurements of specific resistance of the soil and additional parameters are required in order to calculate the final result.…”

“…The other technique represents the smart ground meter (SGM) method which is based on the ground potential difference. Each method has its advantages and disadvantages that are listed in [2][3][4][5][6][7] and discussed in [5].…”

“…Therefore, any potential interference and disturbance voltages must be eliminated. Several different processes or methods [1,3,[5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] are used to eliminate the disturbance voltages. If the disturbance voltage during the measurements is not eliminated, the value of the impedance to earth, and the touch and step voltages can severely deviate from the real value.…”

A Comparative Analysis of Step and Touch Voltages Depending on Two Test Voltage Waveforms

“…The main functions of grounding is in preventing electric shocks to the human body and to protect electrical installations from a potential rise in current due to breakdown, lightning, or overvoltage by allowing the fault current to flow to the ground [1][2][3][4]. The performance of the grounding system, especially in regards to electric shock, is evaluated using step and the touch voltages.…”