TY JOUR TI METHODS OF ESTIMATION OF THE TECHNICAL STATE OF THE ELECTRICAL EQUIPMENT UNDER THE CONDITIONS OF PARAMETRIC FAILURES KW unsafe state KW limit state KW gradual failure KW operation KW critical parameter KW probability KW ageing of insulation JO Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies AU Belov, O.. PY 2015 IS 2015 PB Astrakhan State Technical University