Abstract: A motor circuit for driving a motor having two independent sets of windings forming 3 or more phases, wherein each phase of a first set is paired with a respective phase of a second set. A first bridge driver circuit has a top side switch and a bottom side switch driving each phase of the first set, and a second bridge driver circuit has a top side switch and a bottom side switch driving each phase of the second set. First and second current determining means determine current flowing in each respective sets of windings independent of the current flowing in the other set of phase windings. A third current determining means is configured to determine the sum of the current flowing in each pair of the N pairs of phases of the motor.

Abstract: A control circuit for a multi-phase motor (57) comprises a plurality of inverter bridges, a plurality of outputs, and at least one isolation switch (62, 63). Each inverter bridge is arranged to provide an output voltage for a phase of the motor (57). Each output is arranged to be coupled to one phase of the motor (57) to provide the output voltage to that phase of the motor (57). Each isolation switch (62, 63) is coupled between one of the inverter bridges and one of the outputs, so as to selectively isolate the output from the inverter bridge. Each isolation switch (62, 63) comprises a Gallium Nitride (GaN) transistor.

Abstract: A method of controlling an electric power assisted steering (EPS) apparatus comprises a plurality of inverter bridges each connected to a multi-phase motor configured to provide power assist to steering of a vehicle. After detection of a failure within one of said inverter bridges, the current flow within the faulty inverter bridge is controlled, and one or more of the other inverter bridges is used to provide power assistance. A control system for an electric power assisted steering (EPS) apparatus comprises a plurality of inverter bridges each connected to a multi-phase motor configured to provide power assist to steering of a vehicle, selection means for selectively operating switches in an inverter bridge in which a failure has been detected to control the current flow within the faulty inverter bridge, and control means for controlling one or more of the other inverter bridges to provide power assistance in accordance with the method.

Abstract: An electric power steering system includes an electric motor configured to provide power to a steering mechanism of a vehicle. A controller operates the electric motor in response to an input. A flash memory device is in communication with the controller. A temperature sensor provides an output indicative of a temperature of a part of the electric power steering system. The controller is configured to power down or prevent power up of the flash memory device if the temperature of the electric power steering system is outside of a predetermined temperature range. A method of operating an electric power steering system includes measuring a temperature of the electric power assisted steering system and switching off a flash memory device of the electric power steering system if the temperature of the electric power steering system is outside of a predetermined temperature range.

Abstract: A method of controlling an electric power assisted steering (EPS) system comprises the steps: During a first mode of operation of the EPS system driving a motor using two inverter bridges simultaneously, the nominal current that is applied to the motor at any time by each bridge being limited to a first value, and during a fault mode of operation driving the motor using only one of the two inverter bridges whereby the nominal current that is applied to the motor at any time in the fault mode is limited to a second value, the method varying the second value as a function of one or more operating parameters of the EPS system whereby the second value is set higher than the first value when it is deemed safe to do so.

Abstract: A method of controlling an electric power assisted steering (EPS) system comprising one or more inverter bridges each connected to a multi-phase motor configured to provide power assist to steering of a vehicle, each inverter comprising a plurality of switching elements each associated with a phase of the motor, is provided. The method comprises, preventing current flow in said one or more affected inverters by applying a gate-source voltage to one or more of the switching elements of the affected inverter bridge(s) in response to detecting a predefined event affecting current flow in one or more of the inverter bridges. A control system for an electric power assisted steering apparatus comprising one or more inverter bridges and a control means configured to control the switching elements in accordance with the method is also provided.

Abstract: A power-assisted steering assembly for a vehicle comprises: a motor shaft for transmitting torque from a motor; a steering rack; a primary transmission mechanism; a secondary transmission mechanism; a motor coupling; and a rack coupling. The primary transmission mechanism is configured to transmit power from the motor shaft to the steering rack and includes a drive belt. The secondary transmission mechanism is configured to transmit power from the motor shaft to the steering rack upon a failure of the primary transmission mechanism. The motor coupling is configured to transmit power from the motor shaft to the primary transmission mechanism and the secondary transmission mechanism. The rack coupling is configured to transmit power from the primary transmission mechanism and the secondary transmission mechanism to the steering rack.

Abstract: A control circuit for a multi-phase motor (57) comprises a plurality of inverter bridges, a plurality of outputs, and at least one isolation switch (62, 63). Each inverter bridge is arranged to provide an output voltage for a phase of the motor (57). Each output is arranged to be coupled to one phase of the motor (57) to provide the output voltage to that phase of the motor (57). Each isolation switch (62, 63) is coupled between one of the inverter bridges and one of the outputs, so as to selectively isolate the output from the inverter bridge. Each isolation switch (62, 63) comprises a Gallium Nitride (GaN) transistor.

Abstract: A monitoring system for an electric power-assisted steering system comprising a DC power supply; an inverter bridge including a plurality of bridge switches selectively connecting phases of a multi-phase electric motor to the DC power supply, the multi-phase electric motor being configured to provide power-assistance to a steering system of a vehicle; a bridge driver circuit for providing control signals to the inverter bridge; and a DC link capacitor circuit interposed between the DC power supply and the inverter bridge, the DC link capacitor circuit at least one DC link capacitor. The monitoring system comprises a monitoring circuit configured to monitor the integrity of the DC link capacitor circuit, and outputting a ripple value indicative of a ripple voltage in an output of the DC power supply; and comparison means for comparing the ripple value with at least one ripple parameter indicative of a fault in the DC link capacitor circuit and determining whether a fault is present.

Abstract: A motor drive stage, particularly for an electric power steering (EPS) system, comprises at least one inverter bridge connected to a multi-phase motor, wherein the inverter bridge comprises a plurality of switching elements arranged as a Z-source or quasi-Z-source inverter bridge with the switching elements each comprising wide band gap semiconductor devices. This arrangement enables very high PWM frequencies to be achieved whilst occupying relatively low amounts of physical space.

Abstract: A motor bridge driver integrated circuit comprises a first set of input ports arranged to receive control signals from a first microprocessor, a second set of input ports arranged to receive control signals from a second microprocessor, and at least one set of output ports arranged to output motor phase switching signals to the switches of a motor bridge. A diagnostic circuit receives and monitors the control signals received from the two microprocessors and from those signals determines which microprocessor is to be treated as a master and which is to be treated as a slave at any given time by the motor bridge driver. An arbitration circuit selectively enables only the master microprocessor to the take control of the motor bridge at any given time while preventing the slave microprocessor from taking control of the motor bridge.

Abstract: A method of operation of an automotive vehicle control system of the kind which includes at least one downstream control subsystem having at least one actuator which modifies the longitudinal or lateral motion of the vehicle in response to received control signals from an upstream subsystem is provided. The method comprises: (a) transmitting in real time to the downstream control sub-system one or more control signals from the upstream, (b) determining that a fault has occurred upstream of the downstream control subsystem which causes the control signals to be erroneous, unreliable or unavailable to the downstream control system, and (c) thereafter using a response plan of action for the downstream subsystem that defines a sequence of operation of the at least one actuator of the down steam sub-system over a period of time and which has been previously stored in a local area of memory accessible to the downstream subsystem.

Abstract: A power-assisted steering assembly for a vehicle comprises: a motor shaft for transmitting torque from a motor; a steering rack; a primary transmission mechanism; a secondary transmission mechanism; a motor coupling; and a rack coupling. The primary transmission mechanism is configured to transmit power from the motor shaft to the steering rack and includes a drive belt. The secondary transmission mechanism is configured to transmit power from the motor shaft to the steering rack upon a failure of the primary transmission mechanism. The motor coupling is configured to transmit power from the motor shaft to the primary transmission mechanism and the secondary transmission mechanism. The rack coupling is configured to transmit power from the primary transmission mechanism and the secondary transmission mechanism to the steering rack.

Abstract: A monitoring system for an electric power-assisted steering system comprising a DC power supply; an inverter bridge including a plurality of bridge switches selectively connecting phases of a multi-phase electric motor to the DC power supply, the multi-phase electric motor being configured to provide power-assistance to a steering system of a vehicle; a bridge driver circuit for providing control signals to the inverter bridge; and a DC link capacitor circuit interposed between the DC power supply and the inverter bridge, the DC link capacitor circuit at least one DC link capacitor. The monitoring system comprises a monitoring circuit configured to monitor the integrity of the DC link capacitor circuit, and outputting a ripple value indicative of a ripple voltage in an output of the DC power supply; and comparison means for comparing the ripple value with at least one ripple parameter indicative of a fault in the DC link capacitor circuit and determining whether a fault is present.

Abstract: A method of controlling an electric power assisted steering (EPS) apparatus comprises a plurality of inverter bridges each connected to a multi-phase motor configured to provide power assist to steering of a vehicle. After detection of a failure within one of said inverter bridges, the current flow within the faulty inverter bridge is controlled, and one or more of the other inverter bridges is used to provide power assistance. A control system for an electric power assisted steering (EPS) apparatus comprises a plurality of inverter bridges each connected to a multi-phase motor configured to provide power assist to steering of a vehicle, selection means for selectively operating switches in an inverter bridge in which a failure has been detected to control the current flow within the faulty inverter bridge, and control means for controlling one or more of the other inverter bridges to provide power assistance in accordance with the method.

Abstract: A method of controlling an electric power assisted steering (EPS) system comprising one or more inverter bridges each connected to a multi-phase motor configured to provide power assist to steering of a vehicle, each inverter comprising a plurality of switching elements each associated with a phase of the motor, is provided. The method comprises, preventing current flow in said one or more affected inverters by applying a gate-source voltage to one or more of the switching elements of the affected inverter bridge(s) in response to detecting a predefined event affecting current flow in one or more of the inverter bridges. A control system for an electric power assisted steering apparatus comprising one or more inverter bridges and a control means configured to control the switching elements in accordance with the method is also provided.

Abstract: A motor circuit for driving one or more motors, which in combination include at least two independent sets of windings forming 3 or more phases, in which each of the phases of a first one of the sets of phase windings is paired with a respective phase of a second one of the sets of phase windings, the circuit comprising a first bridge driver circuit comprising for each phase of a first one of the sets of phase windings a top side switch and a bottom side switch, a second bridge driver circuit comprising for each phase of a second of the sets of phase windings a top side switch and a bottom side switch, a first current determining means for determining the current flowing in each phase of the first set of phase windings independent of the current flowing in the second set of phase windings, a second current determining means for determining the current flowing in each phase of the first set of phase windings independent of the current flowing in the first set of phase windings; and a third current determining

Abstract: A motor bridge driver integrated circuit comprises a first set of input ports arranged to receive control signals from a first microprocessor, a second set of input ports arranged to receive control signals from a second microprocessor, and at least one set of output ports arranged to output motor phase switching signals to the switches of a motor bridge. A diagnostic circuit receives and monitors the control signals received from the two microprocessors and from those signals determines which microprocessor is to be treated as a master and which is to be treated as a slave at any given time by the motor bridge driver. An arbitration circuit selectively enables only the master microprocessor to the take control of the motor bridge at any given time whilst preventing the slave microprocessor from taking control of the motor bridge.

Abstract: A measurement circuit in a motor circuit generates signals for use in a motor control strategy for an electric motor. The measurement circuit comprises a first current sensing means which produces an output signal indicative of the current flowing in a di/dt path connecting the phases of the motor to a ground or a common positive supply voltage, and further comprises a second current sensing means which produces an output signal indicative of the rate of change of current flowing in the ground line, and in which the second current sensing means comprises a Rogowski coil.

Abstract: A measurement circuit in a motor circuit generates signals for use in a motor control strategy for an electric motor. The measurement circuit comprises a first current sensing means which produces an output signal indicative of the current flowing in a di/dt path connecting the phases of the motor to a ground or a common positive supply voltage, and further comprises a second current sensing means which produces an output signal indicative of the rate of change of current flowing in the ground line, and in which the second current sensing means comprises a Rogowski coil.