FIELD: physics.
SUBSTANCE: instantaneous voltage and current values are measured in the same time instants tj=t1,t2,…,tn with sampling interval 
where T is the period of the current/voltage signal; N is the number of readings per period T. Said values are stored as present values. Further, active power loss ΔP on ohmic resistance of the capacitor, reactive power Q and the current value of current I are simultaneously determined. After that parametres of the series equivalent circuit of the power capacitor are determined: ohmic resistance 
and capacitance: 
where ω is angular frequency.
EFFECT: avoiding the need for additional measurements.
3 dwg, 3 tbl
