Abstract: A turbomachine having a rotor assembly, a stator assembly and a toroidal inductor. The rotor assembly includes an impeller. The inductor is located between the impeller and the stator assembly, and is exposed to an airflow generated by or acting upon the impeller.

Abstract: An electric motor including: a frame; a rotor assembly including a magnet, a bearing assembly, an impeller, and a shaft; and a stator assembly including a stator core and a bobbin. The frame has an inner wall and an outer wall, the outer wall surrounds the inner wall and defines an annular channel between the inner wall and the outer wall, and diffuser vanes extend from the inner wall to the outer wall through the annular channel. The inner wall defines a bore for supporting the rotor assembly, and the outer wall defines a substantially cylindrical outer casing of the motor.

Abstract: A four-pole stator assembly including a bobbin assembly; and two c-shaped stator cores, each c-shaped stator core comprising a back and first and second pole arms extending from the back. The bobbin assembly includes first and second bobbin portions, each bobbin portion comprising two hollow bobbin arms, each bobbin arm defining a slot for receiving a pole arm, and a winding wound around each bobbin arm. The c-shaped stator cores are arranged such that each c-shaped stator core bridges across both bobbin portions with one of the first and second pole arms extending through a slot in the first bobbin portion, and the other of the first and second pole arms extending through a slot in the second bobbin portion, the pole arms being fixed in the slots by adhesive.

Abstract: An electric motor comprising: a stator assembly; a rotor assembly; and a support body. The stator assembly comprises a plurality of stator elements, and the rotor assembly comprises a shaft to which is mounted at least a first and a second bearing mounted either side of a permanent magnet. The support body comprises an elongate central part, and first and second bearing seats positioned axially at opposite ends of the elongated central part to each other, and the elongate central part defines a plurality of openings each configured to receive one of the plurality of stator elements.

Abstract: An electric motor comprising: a stator assembly; a rotor assembly; and a support body. The stator assembly comprises a plurality of stator elements, and the rotor assembly comprises a shaft to which is mounted at least a first and a second bearing mounted either side of a permanent magnet. The support body comprises an elongate central part, and first and second bearing seats positioned axially at opposite ends of the elongated central part to each other, and the elongate central part defines a plurality of openings each configured to receive one of the plurality of stator elements.

Abstract: An AC/AC boost converter comprising input terminals, output terminals, an inductor, a bridge arm comprising a pair of bi-directional switches, a capacitor and a control circuit for controlling the switches. The bridge arm and the capacitor are connected in parallel across the output terminals. The inductor has a first end connected to one of the input terminals and a second end connected to one of an end and a junction of the bridge arm, the junction being located between the two switches. Another of the input terminals is then connected to the other of the end and the junction of the bridge arm. An AC power supply supplies an AC input voltage at the input terminals, and the control circuit controls the switches of the bridge arm such that an AC output voltage is supplied at the output terminals, the AC output voltage being greater than the AC input voltage.

Abstract: A product that includes a compressor, a housing and a vibration isolation mount located between the compressor and the housing. The compressor includes an impeller, a first inlet located upstream of the impeller, a first outlet located downstream of the impeller, a second inlet located downstream of the first outlet, and a second outlet located downstream of the second inlet. During operation, fluid enters the compressor via the first inlet and exits the compressor via the first outlet. The mount creates a restriction between the compressor and the housing that causes fluid exiting the first outlet to re-enter the compressor via the second inlet.

Abstract: A method of controlling an electric machine, the method comprising storing a plurality of power maps, each power map comprising control values for driving the electric machine at different power, and selecting a power map in response to an input signal. Additionally, a control system for an electric machine, and a product incorporating the control system and electric machine.

Abstract: An electric motor including: a frame; a rotor assembly including a magnet, a bearing assembly, an impeller, and a shaft; and a stator assembly including a stator core and a bobbin. The frame has an inner wall and an outer wall, the outer wall surrounds the inner wall and defines an annular channel between the inner wall and the outer wall, and diffuser vanes extend from the inner wall to the outer wall through the annular channel. The inner wall defines a bore for supporting the rotor assembly, and the outer wall defines a substantially cylindrical outer casing of the motor.

Abstract: A four-pole stator assembly including a bobbin assembly; and two c-shaped stator cores, each c-shaped stator core comprising a back and first and second pole arms extending from the back. The bobbin assembly includes first and second bobbin portions, each bobbin portion comprising two hollow bobbin arms, each bobbin arm defining a slot for receiving a pole arm, and a winding wound around each bobbin arm. The c-shaped stator cores are arranged such that each c-shaped stator core bridges across both bobbin portions with one of the first and second pole arms extending through a slot in the first bobbin portion, and the other of the first and second pole arms extending through a slot in the second bobbin portion, the pole arms being fixed in the slots by adhesive.

Abstract: A stator core that includes a pair of poles separated by an air gap. Each pole includes a first side adjacent the air gap and a second opposite side remote from the air gap. A pole arc is formed in the first side and an arcuate mounting recess is formed in the second side of each pole. Additionally, an electric machine that includes the stator core.

Abstract: An AC/AC boost converter comprising input terminals, output terminals, an inductor, a bridge arm comprising a pair of bi-directional switches, a capacitor and a control circuit for controlling the switches. The bridge arm and the capacitor are connected in parallel across the output terminals. The inductor has a first end connected to one of the input terminals and a second end connected to one of an end and a junction of the bridge arm, the junction being located between the two switches. Another of the input terminals is then connected to the other of the end and the junction of the bridge arm. An AC power supply supplies an AC input voltage at the input terminals, and the control circuit controls the switches of the bridge arm such that an AC output voltage is supplied at the output terminals, the AC output voltage being greater than the AC input voltage.

Abstract: A turbomachine having a rotor assembly, a stator assembly and a toroidal inductor. The rotor assembly includes an impeller. The inductor is located between the impeller and the stator assembly, and is exposed to an airflow generated by or acting upon the impeller.

Abstract: A turbomachine having a rotor assembly, a stator assembly and a toroidal inductor. The rotor assembly includes an impeller. The inductor is located between the impeller and the stator assembly, and is exposed to an airflow generated by or acting upon the impeller.

Abstract: An electric machine that includes a permanent-magnet rotor and a stator. The stator includes a plurality of poles, each pole having a leading edge and a trailing edge relative to the direction of rotation of the rotor. The leading edge of each pole is thicker than the trailing edge in a direction normal to the rotational axis of the rotor.

Abstract: A vacuum cleaner that includes a suction source, a cleaner head, and a controller. The suction source includes an impeller and a first motor for driving the impeller, and the cleaner head includes an agitator and a second motor for driving the agitator. The controller is configured to generate control signals for controlling simultaneously the excitation of the first motor and the second motor.

Abstract: A drive circuit for a brushless motor comprising power lines for carrying an AC voltage, an inverter, and a controller. Each leg of the inverter is connected to a winding of the motor and comprises one or more bi-directional switches. The controller can output control signals that cause a pair of switches to conduct in one direction during the positive half-cycle of the AC voltage, and to conduct in the opposite direction during the negative half-cycle of the AC voltage. Alternatively, The controller can output control signals that cause a first pair of switches to conduct during the positive half-cycle of the AC voltage and a second pair of switches to conduct during the negative half-cycle of the AC voltage such that the winding is excited in the same direction irrespective of the polarity of the AC voltage.

Abstract: A turbomachine that includes a housing and a circuit assembly. The housing includes an inlet for admitting a working airflow and a flange that extends from the inlet. The circuit assembly includes a circuit board and an electrical component having a heat sink. The circuit assembly is located within the housing such that the flange extends beyond the circuit board and the heat sink extends beyond the flange.

Abstract: A method of controlling a brushless motor that includes rectifying an alternating voltage to provide a rectified voltage having a ripple of at least 50%, exciting a winding of the motor with the rectified voltage, and performing a first process or a second process in response to current in the winding exceeding a threshold that is proportional to the rectified voltage. The first process includes freewheeling the winding, while the second process includes continuing to excite the winding for an overrun period and freewheeling the winding at the end of the overrun period. Additionally, a control system that implements the method, and a motor system that incorporates the control system.

Abstract: A method of controlling a brushless permanent-magnet motor that includes rectifying an alternating voltage to provide a rectified voltage having a ripple of at least 50%, and exciting a winding of the motor with the rectified voltage. The winding is excited in advance of zero-crossings of back EMF by an advance period and is excited for a conduction period over each electrical half-cycle of the motor. The advance period and/or the conduction period are then adjusted in response to changes in the speed of the motor and/or the RMS value of the alternating voltage so as to maintain constant average power. Additionally, a control system that implements the method, and a motor system that incorporates the control system.