Method of measuring the state of health at several instants ti of at least one solid-state power electronic component by calculating a quantitative indicator D(ti) of the degradation of the power electronic component, in order to determine the evolution of the ageing of said power electronic component, the power electronic component comprising at least one input terminal and one output terminal for an electric current of intensity I, between which a voltage V is established, the power electronic component having a zero temperature coefficient point ZCP defined by an electric current intensity I,ZCP and a voltage V,ZCP, ZCP being independent of temperature, the method using an electric current sensor, an electric voltage sensor and a processor exchanging information with said sensors, the method comprising: a- a first step of determining, at an initial time t0, a first value of the current I =I,ZCP0 when the electric voltage V is equal to a voltage V =V, ZCPO, the power electronic component then being in an 'initial instant' state; b- a step of measuring a value of the current I at each subsequent instant ti, when the voltage V at instant ti of the power electronic component is equal to the voltage V,ZCPO, the power electronic component then being in an 'instant ti' state; c- a step in which the processor calculates a quantitative indicator D(ti) of the ageing of the power electronic component at each subsequent instant ti, the value of which is a function of the variation in the value of the current I between the 'initial instant' state and the 'instant ti', the ageing being independent of the voltage V,ZCP but dependent on the intensity I,ZCP which decreases with ageing. the power electronic component comprising at least one input terminal and one output terminal for an electric current of intensity I, between which a voltage V is established, the power electronic component having a zero temperature coefficient point ZCP defined by an electric current intensity I,ZCP and a voltage V,ZCP, ZCP being independent of temperature, the method using an electric current sensor, an electric voltage sensor and a processor exchanging information with said sensors, the method comprising: a- a first step of determining, at an initial time t0, a first value of the current I =I,ZCP0 when the electric voltage V is equal to a voltage V =V, ZCPO, the power electronic component then being in an 'initial instant' state; b- a step of measuring a value of the current I at each subsequent instant ti, when the voltage V at instant ti of the power electronic component is equal to the voltage V,ZCPO, the power electronic component then being in an 'instant ti' state; c- a step in which the processor calculates a quantitative indicator D(ti) of the ageing of the power electronic component at each subsequent instant ti, the value of which is a function of the variation in the value of the current I between the 'initial instant' state and the 'instant ti', the ageing being independent of the voltage V,ZCP but dependent on the intensity I,ZCP which decreases with ageing. a- a first step of determining, at an initial time t0, a first value of the current I =I,ZCP0 when the electric voltage V is equal to a voltage V =V, ZCPO, the power electronic component then being in an 'initial instant' state; b- a step of measuring a value of the current I at each subsequent instant ti, when the voltage V at instant ti of the power electronic component is equal to the voltage V,ZCPO, the power electronic component then being in an 'instant ti' state; c- a step in which the processor calculates a quantitative indicator D(ti) of the ageing of the power electronic component at each subsequent instant ti, the value of which is a function of the variation in the value of the current I between the 'initial instant' state and the 'instant ti', the ageing being independent of the voltage V,ZCP but dependent on the intensity I,ZCP which decreases with ageing.