An electric power system includes a variable-frequency drive and a control module. The variable-frequency drive includes a first power converter, a second power converter and at least one energy storage module. The first power converter is connected between a DC bus and a power terminal. Moreover, electric energy is transferred between the first power converter and the power terminal at a first power. The second power converter is connected between the DC bus and an electric/kinetic energy conversion device. Moreover, electric energy is transferred between the second power converter and the electric/kinetic energy conversion device at a second power. As the second power is dynamically changed, the control module controls a charge/discharge operation of the at least one energy storage module. As a consequence, the operational change of the electric/kinetic energy conversion device is reversely compensated.

A superconducting current pump arranged to cause a DC electrical current to flow through a superconducting circuit accommodated within a cryogenic enclosure of a cryostat comprises a rotor external to the cryogenic enclosure and a stator within the cryogenic enclosure, the rotor and stator separated by a gap through which passes a thermally insulating wall of the cryogenic enclosure, the rotor and the stator comprising at least in part a ferromagnetic material to concentrate magnetic flux in a magnetic circuit across the gap between the rotor and the stator and through the wall, so that movement of the rotor external to the cryogenic enclosure relative to the stator within the cryogenic enclosure induces a DC transport current to flow around the superconducting circuit within the cryogenic enclosure. There is no coupling between a drive motor external to the cryogenic enclosure and an internal rotor which may introduce a path for heat leakage into the cryostat, in turn increasing the heat load and thus increasing the cooling power required to maintain the cold components within the cryogenic enclosure at the low operating temperature required.

A closed-loop circuit is detected based on a short-circuit failure of a motor control switching element of a motor drive circuit and a cutoff switching element. A motor control device including a motor, a motor drive circuit (10a) that is connected to a power supply device and the motor and controls the output of the motor, and a processing unit for detecting a closed-loop circuit formed by the motor and the motor drive circuit (10a) based on a short-circuit failure of switching elements arranged in the motor drive circuit (10a).

An electric motor system having substantially independent hardware-based and software-based pathways for detecting and initiating responses to fault conditions, such as over-current conditions, in an electric motor which is powered by a power inverter which is controlled by a power module and a microprocessor. Each pathway involves comparing a voltage, which is representative of an electric current flowing to the motor, to a predetermined maximum voltage, and if the former exceeds the latter using hardware or software to initiate shutting off the motor, such as by shutting off the power inverter. When one pathway detects a fault condition it may notify the other pathway, and the notified pathway may also initiate shutting off the motor.

A roll shade system is disclosed. The roll shade system includes a motor configured to remain stationary during operation of the motor, a support shaft supporting the motor wherein the support shaft is configured to remain stationary during operation of the motor, and a roll shade tube configured to be rotatable about the motor and the support shaft during operation of the motor. The roll shade system further includes stationary components including a wiring connector, an input wiring system, a bearing, an antenna, a coaxial cable, a motor controller, a counterbalance spring. The roll shade system also includes rotatable components including a bearing housing and one or more O-rings.

A lead screw attachment mechanism for a linear actuator system is provided. The attachment mechanism comprises an attachment housing comprising a fixed cover configured to house the attachment mechanism. The attachment mechanism comprises a first coupling mechanism configured to couple the attachment mechanism to an output shaft of a motor and a second coupling mechanism configured to couple the attachment mechanism to a lead nut, wherein the lead nut is configured to move linearly along an axis defined by a length of the attachment mechanism. The attachment mechanism is configured to rotate about the axis, within the fixed cover.

A lead screw attachment mechanism for a linear actuator system is provided. The attachment mechanism comprises an attachment housing comprising a fixed cover configured to house the attachment mechanism. The attachment mechanism comprises a first coupling mechanism configured to couple the attachment mechanism to an output shaft of a motor and a second coupling mechanism configured to couple the attachment mechanism to a lead nut, wherein the lead nut is configured to move linearly along an axis defined by a length of the attachment mechanism. The attachment mechanism is configured to rotate about the axis, within the fixed cover.

A system, in one embodiment, includes a drive having a housing, a stator disposed in the housing, a rotor disposed in the stator, and a programmable logic controller disposed inside, mounted on, or in general proximity to the housing. In another embodiment, a system includes a network, a first motor having a first integral programmable logic controller coupled to the network, and a second motor having a second integral programmable logic controller coupled to the network. In a further embodiment, a system includes a rotary machine having a rotor and a stator disposed concentric with one another, a microprocessor, memory coupled to the microprocessor, a power supply coupled to the microprocessor and the memory, and a machine sensor coupled to the microprocessor.

A protective redundancy circuit is provided for a power tool having an electric motor. The protective redundant subsystem is comprised of: a motor switch coupled in series with the motor; a motor control module that controls the switching operation of the motor switch; and a protective control module that monitors switching operation of the motor switch and disables the power tool when the switching operation of the motor switch fails. In the context of an AC powered tool, the switching operation of the motor switch is correlated to and synchronized to the waveform of the AC input signal. During each cycle or half cycle, the motor control module introduces a delay period before closing the motor switch and the protective control module determines the operational status of the motor switch by measuring the voltage across the motor switch during the delay period.

A protective redundancy circuit is provided for a power tool having an electric motor. The protective redundant subsystem is comprised of: a motor switch coupled in series with the motor; a motor control module that controls the switching operation of the motor switch; and a protective control module that monitors switching operation of the motor switch and disables the power tool when the switching operation of the motor switch fails. In the context of an AC powered tool, the switching operation of the motor switch is correlated to and synchronized to the waveform of the AC input signal. During each cycle or half cycle, the motor control module introduces a delay period before closing the motor switch and the protective control module determines the operational status of the motor switch by measuring the voltage across the motor switch during the delay period.