A de-exciting system for dissipating energy from an inductive circuit that comprises at least one coil adapted to be attached to said inductive circuit and comprising a series connection of a discharge resistor and a unidirectional discharge switching element; a unidirectional bypass switching element that is connected in parallel to the discharge resistor such that, when the de-exciting system is attached to the inductive circuit and both the discharge switching element and the bypass switching element are in a conducting state, a closed conducting path comprising the coil, the discharge switching element, and the bypass switching element is formed; and a control device configured to, in a first de-excitation phase, switch both the discharge switching element and the bypass switching element into a conducting state, and in a second de-excitation phase, switch the bypass switching element into a non-conducting state, while keeping the discharge switching element in the conducting state.

A control apparatus is applied to a system that includes a rotating electric machine and an inverter. The inverter has, for each of a plurality of phases, upper-arm and lower-arm switches each of which has a diode connected in antiparallel thereto. The control apparatus includes an all-phase short-circuiting unit and a single-phase short-circuiting unit. The all-phase short-circuiting unit performs all-phase short-circuit control of turning on, for example, all the upper-arm switches of the plurality of phases while turning off all the lower-arm switches of the plurality of phases. The single-phase short-circuiting unit performs, in a regenerative drive state of the rotating electric machine and prior to execution of the all-phase short-circuit control, single-phase short-circuit control of turning on one of the upper-arm and lower-arm switches of one of the plurality of phases, turning off the other switch of the phase and turning off all the switches of the remaining phases.

A method of updating a thermal model describing the thermal behaviour of an electric motor having a stator provided with stator windings, the method including: a) injecting a current into the stator windings to heat the stator windings, b) obtaining temperature measurements over time from each of a plurality of temperature sensors distributed in the electric motor while step a) is being performed and the stator windings are heating up, or after step a) has been terminated or the current has been decreased, and the electric motor is cooling down, and c) updating parameter values of the thermal model based on the temperature measurements.