Abstract: A controller for a switched reluctance machine is operated to close a switch which would otherwise be open so as to connect a phase winding to the DC link to which the winding is connected during other parts of the electrical cycle. This produces a condition which allows the insulation of the system to be monitored by applying a voltage between the DC link and ground.

Abstract: A controller for a switched reluctance machine is operated to close a switch which would otherwise be open so as to connect a phase winding to the DC link to which the winding is connected during other parts of the electrical cycle. This produces a condition which allows the insulation of the system to be monitored by applying a voltage between the DC link and ground.

Abstract: An electrical drive system includes an electrical machine controlled by an electronic controller and requires control signals representing quantities associated with the operation of the electrical machine. These signals may represent, for example, rotor position and flux or current. A controller includes an estimation routine to use the known magnetic characteristics of the machine and a rotor position signal to provide an estimate of current or of supply voltage.

Abstract: An electrical machine has a rotor position transducer which provides output signals to a control system. The output signals contain errors due to component shortcomings and manufacturing imperfections. A method is disclosed which is able to determine the errors in the signals by the use of a position detection algorithm so as to provide compensations to the control system of the machine. The compensations may be stored in the control system and used to improve the accuracy of the transducer output signals, thus improving the output of the machine.

Abstract: An electrical drive system includes an electrical machine controlled by an electronic controller and requires control signals representing quantities associated with the operation of the electrical machine. These signals may represent, for example, rotor position and flux or current. A controller includes an estimation routine to use the known magnetic characteristics of the machine and a rotor position signal to provide an estimate of current or of supply voltage.

Abstract: A switched reluctance machine is energized by phase circuits with four active switches, for example MOSFETs, arranged in a bridge configuration. The switches are capable of conducting current in both a first direction and a second direction and are capable of operating as a diode. The direction of current flow through the phase winding is reversed when changing from motoring to generating and from generating to motoring. The ratings of the switches are set in accordance with the energy supply and energy return currents.

Abstract: An electrical machine has a rotor position transducer which provides output signals to a control system. The output signals contain errors due to component shortcomings and manufacturing imperfections. A method is disclosed which is able to determine the errors in the signals by successively running the machine with a series of assumed errors in the rpt signals and building up a set of test results. These results are subsequently compared with each other so as to determine the optimum value of corrections to the control system of the machine. The correction may be stored in the control system and used to improve the accuracy of the transducer output signals, thus improving the output of the machine.

Abstract: An electrical machine has a rotor position transducer which provides output signals to a control system. The output signals contain errors due to component shortcomings and manufacturing imperfections. A method is disclosed which is able to determine the errors in the signals by comparison with calibrated data, so as to provide corrections to the control system of the machine. The corrections may be stored in the control system and used to improve the accuracy of the transducer output signals, thus improving the output of the machine.

Abstract: An electrical machine has phase windings composed of coils connected in parallel. A current transducer is arranged to measure the current in only one of the coils and the total phase current is determined by scaling the output of the transducer according to the number of parallel branches in the phase winding.

Abstract: A switched reluctance drive is supplied from a power source and has a DC link, across which is a DC link capacitor. The phases of the machine are controlled by a controller which controls the switches connecting each phase winding to the DC link. The controller switches off the switches of each phase in a sequence which minimizes the peak voltage appearing on the DC link capacitor, thereby allowing a reduction in the voltage rating of the capacitor.

Abstract: A coil is fabricated as two or more tracks of a printed circuit board and arranged close to a conductor to measure the rate of change of current in the conductor. Each turn of the coil is displaced from its neighboring turn in a direction parallel to the direction of the conductor. The output from the coil may be used to provide a detection signal for a position detection scheme in a switched reluctance drive.

Abstract: A switched reluctance machine is energized by phase circuits with four active switches, for example MOSFETs, arranged in a bridge configuration. The switches are capable of conducting current in both a first direction and a second direction and are capable of operating as a diode. The direction of current flow through the phase winding is reversed when changing from motoring to generating and from generating to motoring. The ratings of the switches are set in accordance with the energy supply and energy return currents.

Abstract: A switched reluctance drive is supplied from a first voltage source (V1) during an idle period, in which it transfers energy to a second voltage source (V2). The machine is subsequently run at high power from the second source (V2), so that the first source (V1) does not have to supply the current required when the machine is operating at high power. The drive is able to regulate the amount of energy transferred to the second source (V2).

Abstract: A switched reluctance drive is supplied from a power source and has a DC link, across which is a DC link capacitor. The phases of the machine are controlled by a controller which controls the switches connecting each phase winding to the DC link. The controller switches off the switches of each phase in a sequence which minimizes the peak voltage appearing on the DC link capacitor, thereby allowing a reduction in the voltage rating of the capacitor.