Symbol	Name	Unit
$A$	mobility constant	S/m
ADC	analogical digital converter	-
$C_p$	parallel capacity	F
$C_N$	reference capacitor	F
$\tilde{D}$	incidence matrix face–volume in dual mesh	-
DSP	digital signal processing (Figure 7a)	-
$\overline{E}$ & ${\overline{E}}^{\ast }$	complex electric field and its conjugate	V/m
$E_{ac}$	activation energy	eV
$f$	frequency	Hz
G, Gt	incidence matrix edges–nodes of primal mesh and transpose mat.	-
$G_p$	conductance	S
$g_1, g_2, g_{sp}$	objective functions	-
$I_c$	incidence vector of relative cohomology between oil volume and electrode surface	-
${\overline{I}}_{Cp}$	complex capacitive current	A
${\overline{I}}_N$	complex reference capacitor intensity	A
${\overline{I}}_{Rp}$	complex resistive current	A
${\overline{I}}_t$	complex total current	A
j	imaginary unit	-
$\overrightarrow{J}$	volumetric density current	A/m2
$K$	Boltzmann constant	J/K
$M_{\epsilon }$	electrical permittivity constitutive matrix	F
Mσ	electric conductivity constitutive matrix	S
$P_{Joule}$	average total losses over time–rms value	W
QF	quality factor	-
$R_p$	parallel resistance	Ω
$R_X,R_N$	highly accurate shunts $R_X$ and $R_N$	Ω
$T$	temperature	°C, K
$t, t_1, t_2$	time	s
$tan \delta$	tangent of delta	-
$tan {\delta }_C$	conduction	-
$tan {\delta }_H$	dielectric hysteresis	-
$tan {\delta }_P$	polarization	-
$tan {\delta }_I$	ionization	-
${\overline{U}}_{\mathit{Test}}$	complex test voltage	V
${\overline{U}}_X, {\overline{U}}_N$	complex voltage in shunts $R_X$ and $R_N$	V
$v$	volume	m3
$W_e$	time-averaged electrical energy–rms value	J
${\overline{Y}}_p$	complex admittance	S
ε	electrical permittivity of the medium	F/m
εr	relative electrical permittivity	-
ε0	electrical permittivity in vacuum	F/m
$\rho$	resistivity	Ω·m
σ	electric conductivity	S/m
φ	scalar electric potential	V
${\phi }_m$	phase difference between voltages ${\overline{U}}_N$ and ${\overline{U}}_X$	rad
${\phi }_X$	angle of ${\overline{I}}_t$	rad
${\phi }_1$	angle of ${\overline{I}}_N$	rad
$\omega$	angular frequency	rad/s