Abstract: A neutral point clamped, multilevel level converter including a DC voltage link having a positive rail and a negative rail; a phase leg coupled to an AC node, the phase leg having a first switch and a second switch in series between the negative rail and the AC node, the phase leg having a third switch and a fourth switch in series between the positive rail and the AC node; and a gate drive power supply having a charge pump section, the charge pump section generating a first gate drive voltage for the first switch and a second gate drive voltage for the second switch.

Abstract: An elevator control system is configured to control an elevator car constructed and arranged to move along a hoistway defined by a stationary structure. The elevator system may include a communication pathway and a hoistway control system supported by the stationary structure and configured to send a continuous brake command signal over the pathway. A car control system is carried by the elevator car and is configured to receive the continuous brake command signal and initiate a brake Ustop mode upon a loss of the brake command signal, and independent of the hoistway control system.

Abstract: A regenerative drive device and a method for configuring the DC link of a regenerative drive device are disclosed. The multilevel regenerative drive device may include an inverter having a plurality of power components and a converter having a plurality of power components. The multilevel regenerative drive device may also include a direct current (DC) link bridging the inverter and the converter, the DC link including a capacitor, an inverter neutral point, and a converter neutral point independent of the inverter neutral point. Alternatively, the inverter neutral point and the converter neutral point may be connected.

Abstract: A method of stopping an elevator in the event of a power failure is provided. The method includes determining that a power source for a drive system of an elevator has failed, retaining energy electrically separate from the power source, managing the retained energy to enable drive-assisted emergency stopping of an elevator, and stopping an elevator using the managed, retained energy.

Abstract: A method (70) for controlling a multilevel regenerative drive (30) having a converter (32) and an inverter (34) is disclosed. The method (70) may include applying at least one of unipolar modulation and bipolar modulation to the converter (32), and applying at least one of unipolar modulation and bipolar modulation to the inverter (34). A control system (52) for a mechanical system (20) having a motor (28) is also disclosed. The control system (52) may comprise a converter (32) operatively connected to a power source (29), and an inverter (34) operatively connected to the motor (28) of the mechanical system (20). At least one controller may be in communication with the converter (32) and inverter (34), and may be configured to apply at least one of unipolar modulation and bipolar modulation to each of the converter (32) and the inverter (34).

Abstract: A control system (48) having a motor (28) is disclosed. The control system (48) may include a converter (32) operatively connected to a power source (36), an inverter (34) operatively connected to the motor (28), and a controller (50) operatively connected to the converter (32) or inverter (34). The controller (50) may be configured to receive control command signals, receive state feedback signals, and generate duty cycle signals for upper and lower arms of each phase (40) of the motor (28) based at least in part on the control command signals and state feedback signals. The duty cycle signals may minimize neutral point current in the converter (32) or inverter (34).

Abstract: A switching assembly for use in a drive unit for driving a motor. The switching assembly includes a gallium nitride switch having a gate terminal, drain terminal and source terminal; a gate driver generating a drive signal; a gate drive circuit including a turn on resistor in series with the gate driver and the gate terminal and a clamping circuit connected across the gate terminal and the source terminal, a turn on drive signal from the gate driver being applied to the gate terminal through the turn on resistor; and a snubber circuit connected across the drain terminal and source terminal.

Abstract: A drive unit for a motor includes a printed circuit board (PCB); a first gallium nitride switch having a gate, the first gallium nitride switch mounted to the PCB; a second gallium nitride switch having a gate, the second gallium nitride switch mounted to the PCB; a gate driver generating a turn-off drive signal to turn off the first gallium nitride switch and turn off the second gallium nitride switch; a first turn-off trace on the PCB, the first turn-off trace directing the turn-off drive signal to the gate of the first gallium nitride switch; and a second turn-off trace on the PCB, the second turn-off trace directing the turn-off drive signal to the gate of the second gallium nitride switch; wherein an impedance of the first turn-off trace is substantially equal to an impedance of the second turn-off trace.

Abstract: A system includes an electronic device, a heat spreader with a vapor chamber attached to a bottom end of the electronic device, so that heat flows from the electronic device to the heat spreader, and a heat sink with microchannels running through it attached to a bottom end of the heat spreader, so that heat from the heat spreader flows through the heat sink and to an ambient. A method for cooling a device includes transferring heat generated by a device through a conductivity layer, spreading the heat through a heat spreader, transferring the heat from the heat spreader to a heat sink that contains microchannels, and releasing the heat from the heat sink into an ambient.

Abstract: A neutral point clamped, multilevel level converter including a DC voltage link having a positive rail and a negative rail; a phase leg coupled to an AC node, the phase leg having a first switch and a second switch in series between the negative rail and the AC node, the phase leg having a third switch and a fourth switch in series between the positive rail and the AC node; and a gate drive power supply having a charge pump section, the charge pump section generating a first gate drive voltage for the first switch and a second gate drive voltage for the second switch.

Abstract: A neutral point clamped, multilevel level converter includes a DC voltage link; a first capacitor coupling one side of the DC link to a neutral point; a second capacitor coupling another side of the DC link to the neutral point; a plurality of phase legs, each phase leg including switches, each phase leg coupled to an AC node; a current sensor associated with each AC node; and a controller generating a PWM signal to control the switches, the controller generating a current zero sequence component in response to current sensed at each of the current sensors, the controller adjusting a modulation index signal in response to the current zero sequence component to produce the PWM signal.

Abstract: A system includes an electronic device, a heat spreader with a vapor chamber attached to a bottom end of the electronic device, so that heat flows from the electronic device to the heat spreader, and a heat sink with microchannels running through it attached to a bottom end of the heat spreader, so that heat from the heat spreader flows through the heat sink and to an ambient. A method for cooling a device includes transferring heat generated by a device through a conductivity layer, spreading the heat through a heat spreader, transferring the heat from the heat spreader to a heat sink that contains microchannels, and releasing the heat from the heat sink into an ambient.

Abstract: A microsource is provided, which includes a generator, a prime mover, and a controller. The prime mover includes a shaft connected to drive the generator to generate power at a frequency controlled by a rotation rate of the shaft. The controller calculates an operating frequency for the generator based on a comparison between a power set point and a measured power flow. A requested shaft speed for the prime mover is calculated by combining a maximum frequency change, a minimum frequency change, and the calculated operating frequency. A shaft speed adjustment is calculated for the prime mover based on a comparison between the requested shaft speed and a measured shaft speed of the prime mover. A fuel command for the prime mover is calculated based on the shaft speed adjustment. A rotation rate of the shaft of the prime mover is adjusted based on the calculated fuel command to control the frequency.

Abstract: A doubly fed axial flux induction generator may include a prime mover configured to provide mechanical energy. The doubly fed axial flux induction generator may also include a rotor assembly coupled to the prime mover, wherein the prime mover is configured to rotate the rotor assembly. The doubly fed axial flux induction generator may further include a stator. The doubly fed axial flux induction generator may further include a power electronics module coupled to the rotor assembly and the stator, wherein the power electronics module is arranged in parallel with the prime mover, and is configured to assist with converting the mechanical energy into electrical energy, as well as with dispatching power between the prime mover and an energy storage device. The energy storage device may be coupled to the power electronics module, and may be configured to meet variations in power demand.