Abstract: An electric power converter for a photovoltaic energy source, including: an inverter to receive a dynamically changing DC signal generated by the photovoltaic energy source and to generate a corresponding dynamically changing AC signal having a frequency substantially equal to a mains supply frequency; and an electromagnetic apparatus, including: a magnetic core and a plurality of windings around the magnetic core. The windings include: one or more input windings to receive the dynamically changing AC signal as an AC input; one or more output windings to provide an AC output signal; and control windings configured to control electromagnetic coupling between the input and output windings; and a control component configured to dynamically control electrical currents through the control windings so that the electrical characteristics of the AC output signal are relatively constant despite the dynamically changing AC signal and include a fundamental frequency equal to the mains supply frequency.

Abstract: An improved method of starting a switched reluctance motor uses two neighbouring pairs of coils, both energised, to bring the rotor to its initial position. Then one of pairs of coils is turned off and the rotor is attracted by the other pair of coils to give it an initial rotational speed. An intermediate stage uses just one pair of coils of the motor to bring it up to operational speeds, after which the normal cycling of all the coils can be used.

Abstract: An improved method of starting a switched reluctance motor uses two neighbouring pairs of coils, both energised, to bring the rotor to its initial position. Then one of pairs of coils is turned off and the rotor is attracted by the other pair of coils to give it an initial rotational speed. An intermediate stage uses just one pair of coils of the motor to bring it up to operational speeds, after which the normal cycling of all the coils can be used.

Abstract: A switched reluctance motor is controlled by sensing the position of the rotor of the motor to provide indications of the timings of one or more positions of the rotor per revolution of the rotor, deriving from those indications, indications of the timings of one or more estimated positions of the rotor between the timings indicated by the sensing, and then energising the stator coils of the motor at those times.

Abstract: A magnetic indicator ring has a set of boundaries between magnetic domains. Some or all of these are to be identified. A reference set of measurements of the angular widths between the boundaries to be identified are measured and recorded. Later a second set of measurements of the widths between those boundaries are made and these widths are matched against the reference set. Matching up widths identifies which of the boundaries are which from the reference set. This enables other data recorded respective to those boundaries to be used. For example the other date may be offsets between the boundaries and the position of a rotor in a switched reluctance motor used to drive the compressor wheel in a supercharger.

Abstract: The present invention relates to a method for transferring a charge from an electricity source to a battery means (21) of an electric device of a motor vehicle, said electric device including: a voltage converter (13) connected to the battery means (21), a capacitor connected to the voltage converter (13), a means for connecting the electric device, intended for being connected to the electricity source, a second voltage converter (14) connected between the first battery means (21) and the first converter (13) as well as to a second battery means (22). The method includes a step of connecting a means for connecting to the electricity source in order to enable a charge transfer towards the battery means (21). The method also includes a step of precharging the capacitor with a predetermined voltage from the voltage provided by the battery means (21) via the voltage converter (13), said precharging step being prior to the transfer of the charge from the electricity source to the battery means (21).