TY - JOUR
T1 - Principles of Charge Estimation Methods Using High-Frequency Current Transformer Sensors in Partial Discharge Measurements
AU - Rodrigo-Mor, Armando
AU - Muñoz, Fabio A.
AU - Castro-Heredia, Luis Carlos
PY - 2020/4/29
Y1 - 2020/4/29
N2 - This paper describes a simplified model and a generic model of high-frequency current transformer (HFCT) sensors. By analyzing the models, a universal charge estimation method based on the double time integral of the measured voltage is inferred. The method is demonstrated to be valid irrespective of HFCT sensor, assuming that its transfer function can be modelled as a combination of real zeros and poles. This paper describes the mathematical foundation of the method and its particularities when applied to measure nanosecond current pulses. In practice, the applicability of the method is subjected to the characteristics and frequency response of the sensor and the current pulse duration. Therefore, a proposal to use the double time integral or the simple time integral of the measured voltage is described depending upon the sensor response. The procedures used to obtain the respective calibration constants based on the frequency response of the HFCT sensors are explained. Two examples, one using a HFCT sensor with a broadband flat frequency response and another using a HFCT sensor with a non-flat frequency response, are presented.
AB - This paper describes a simplified model and a generic model of high-frequency current transformer (HFCT) sensors. By analyzing the models, a universal charge estimation method based on the double time integral of the measured voltage is inferred. The method is demonstrated to be valid irrespective of HFCT sensor, assuming that its transfer function can be modelled as a combination of real zeros and poles. This paper describes the mathematical foundation of the method and its particularities when applied to measure nanosecond current pulses. In practice, the applicability of the method is subjected to the characteristics and frequency response of the sensor and the current pulse duration. Therefore, a proposal to use the double time integral or the simple time integral of the measured voltage is described depending upon the sensor response. The procedures used to obtain the respective calibration constants based on the frequency response of the HFCT sensors are explained. Two examples, one using a HFCT sensor with a broadband flat frequency response and another using a HFCT sensor with a non-flat frequency response, are presented.
KW - high-frequency current transformer
KW - HFCT
KW - Rogowski coils
KW - magnetic loop antenna
KW - partial discharge
KW - PD
KW - magnetically coupled sensors
KW - charge estimation
UR - http://www.scopus.com/inward/record.url?scp=85084276432&partnerID=8YFLogxK
U2 - 10.3390/s20092520
DO - 10.3390/s20092520
M3 - Article
VL - 20
SP - 1
EP - 16
JO - Sensors
JF - Sensors
SN - 1424-8220
IS - 9
M1 - 2520
ER -