A switch controller coupled to control a transistor. The switch controller comprising an interface coupled to receive a command signal in response to an event sensed in a control system. The command signal is representative of a first command to control the transistor with a first drive strength or a second command to control the transistor with a second drive strength. The switch controller is coupled to adjust a fall time or a rise time, or to adjust both the fall time and the rise time, of a voltage across the transistor in response to the command signal. The fall time or the rise time, or both the fall time and the rise time in response to the second command is shorter than the fall time or the rise time, or both the fall time and the rise time in response to the first command.

A motor system comprises a motor comprising: a stator with a plurality of subwindings each having a plurality of phase connections for receiving phase voltages, wherein each of the subwindings is electrically insulated from each of the other subwindings; a rotor comprising a plurality of permanent magnets or energisable electromagnets; a controller comprising a plurality of control parts, each control part associated with a respective subwinding, each control part being configured to monitor phase voltages of the associated subwinding, between phase connections. The system further comprises a controller configured to: obtain, from each control part, at set discrete time intervals, a plurality of back measured electromotive force, EMF, readings for each of the respective subwindings; using the plurality of measured back EMF readings and an a priori knowledge of the motor's construction to estimate a commutation event timing.

A motor system comprises a motor comprising: a stator with a plurality of subwindings each having a plurality of phase connections for receiving phase voltages, wherein each of the subwindings is electrically insulated from each of the other subwindings; a rotor comprising a plurality of permanent magnets or energisable electromagnets; a controller comprising a plurality of control parts, each control part associated with a respective subwinding, each control part being configured to monitor phase voltages of the associated subwinding, between phase connections. The system further comprises a controller configured to: obtain, from each control part, at set discrete time intervals, a plurality of back measured electromotive force, EMF, readings for each of the respective subwindings; using the plurality of measured back EMF readings and an a priori knowledge of the motor's construction to estimate a commutation event timing.

A control system configured to control a transistor configured to control energy delivery to a load. The control system comprises a system controller to sense an event in the control system and to assert a command signal in response to the sensed event and a switch controller configured to receive the command signal. The switch controller is configured to control the turn on and the turn off of the transistor, wherein the system controller controls the turn on or the turn off, or control both the turn on and the turn off of the transistor with a first drive strength in response to a first command in the command signal and controls the turn on or the turn off, or control both the turn on and the turn off of the transistor with a second drive strength in response to a second command in the command signal.

A control system configured to control a transistor configured to control energy delivery to a load. The control system comprises a system controller to sense an event in the control system and to assert a command signal in response to the sensed event and a switch controller configured to receive the command signal. The switch controller is configured to control the turn on and the turn off of the transistor, wherein the system controller controls the turn on or the turn off, or control both the turn on and the turn off of the transistor with a first drive strength in response to a first command in the command signal and controls the turn on or the turn off, or control both the turn on and the turn off of the transistor with a second drive strength in response to a second command in the command signal.

A control system to control a conductivity modulated device of a power switching array. The control system comprises a system controller to sense a power event and to output a command signal to adjust a drive characteristic of the conductivity modulated device in response to the sensed power event and a switch controller configured to receive the command signal and to control energy delivery to the load by controlling the turn on and turn off of the conductivity modulated device. The switch controller includes an adjustable drive element to control a rise time and/or fall time of a voltage across the conductivity modulated device and a drive characteristic control to receive the command signal and vary the drive characteristics by control of the adjustable drive element to adjust the rise time and/or fall time of the voltage across the conductivity modulated device in response to the command signal.

A control system to control a conductivity modulated device of a power switching array. The control system comprises a system controller to sense a power event and to output a command signal to adjust a drive characteristic of the conductivity modulated device in response to the sensed power event and a switch controller configured to receive the command signal and to control energy delivery to the load by controlling the turn on and turn off of the conductivity modulated device. The switch controller includes an adjustable drive element to control a rise time and/or fall time of a voltage across the conductivity modulated device and a drive characteristic control to receive the command signal and vary the drive characteristics by control of the adjustable drive element to adjust the rise time and/or fall time of the voltage across the conductivity modulated device in response to the command signal.

According to one embodiment, a power generation system includes a power generator, a displacement measuring part, and a converter. The power generator includes a movable part and converts mechanical energy of the movable part into electric power. The displacement measuring part measures a displacement of the movable part. The converter includes a switching circuit whose duty ratio is controlled based on the measured displacement, and converts a voltage level of the electric power.

According to one embodiment, a power generation system includes a power generator, a displacement measuring part, and a converter. The power generator includes a movable part and converts mechanical energy of the movable part into electric power. The displacement measuring part measures a displacement of the movable part. The converter includes a switching circuit whose duty ratio is controlled based on the measured displacement, and converts a voltage level of the electric power.

A piezoelectric driving device includes a vibrating plate, and a piezoelectric vibrating body including a substrate, and piezoelectric elements provided on the substrate. The piezoelectric element includes a first electrode, a second electrode, and a piezoelectric body, and the first electrode, the piezoelectric body, and the second electrode are laminated in this order on the substrate. The piezoelectric vibrating body is installed on the vibrating plate so that the piezoelectric element is interposed between the substrate and the vibrating plate. A wiring pattern including a first wiring corresponding to the first electrode and a second wiring corresponding to the second electrode is formed on the vibrating plate, the first electrode and the first wiring are connected to each other through a first laminated conducting portion, and the second electrode and the second wiring are connected to each other through a second laminated conducting portion.