An electronic circuit comprises a charge storing component, a set of one or more switching components coupled to the charge storing component, and an additional switching component coupled to each of the one or more switching components in the set. The additional switching component is configured to operate in a first state or a second state based on a received current or voltage. The first state prevents current to flow from the charge storing component to each of the one or more switching components in the set and the second state allows current to flow from the charge storing component to each of the one or more switching components in the set.

A drive apparatus includes a DC link; a rectifier to convert power of an external power supply into predetermined DC power to be supplied to the DC link; a motor to rotationally drive a compression mechanism; a supporter to magnetically support a rotating shaft of the compression mechanism; a first driver to drive the motor with power from the DC link, to cause the motor to execute regenerative operations of converting power from the rotating shaft into electric energy, and to output regenerative power to the DC link; and a second driver to drive the supporter with the power from the DC link, wherein the first driver causes the motor to execute the regenerative operations so that a voltage of the DC link becomes higher than a voltage of the DC link when the power of the external power supply is normally supplied.

A drive apparatus includes a DC link; a rectifier to convert power of an external power supply into predetermined DC power to be supplied to the DC link; a motor to rotationally drive a compression mechanism; a supporter to magnetically support a rotating shaft of the compression mechanism; a first driver to drive the motor with power from the DC link, to cause the motor to execute regenerative operations of converting power from the rotating shaft into electric energy, and to output regenerative power to the DC link; and a second driver to drive the supporter with the power from the DC link, wherein the first driver causes the motor to execute the regenerative operations so that a voltage of the DC link becomes higher than a voltage of the DC link when the power of the external power supply is normally supplied.

An electric power tool in one aspect of the present disclosure includes a motor, first and second paths respectively and electrically connect the motor to a DC power supply, a first switch on the first path, a second switch on a the second path, a first drive circuit, and first and second holding circuits. The first drive circuit (i) switches the first switch to the ON-state and (ii) outputs a first drive signal to the second switch. The first holding circuit holds the second switch in the ON-state while the first drive circuit is activated. The second holding circuit holds the first switch in the OFF-state based on the second switch being held in the ON-state.

An electric power tool in one aspect of the present disclosure includes a motor, first and second paths respectively and electrically connect the motor to a DC power supply, a first switch on the first path, a second switch on a the second path, a first drive circuit, and first and second holding circuits. The first drive circuit (i) switches the first switch to the ON-state and (ii) outputs a first drive signal to the second switch. The first holding circuit holds the second switch in the ON-state while the first drive circuit is activated. The second holding circuit holds the first switch in the OFF-state based on the second switch being held in the ON-state.

A power converter according to an aspect of an embodiment includes: a diode converter; an inverter; a smoothing capacitor; a resistor; a current sensor; an estimation unit; and a control unit. The diode converter rectifies an alternating current from a power supply. The inverter is formed such that a DC side is connected to a DC output of the diode converter and an AC side is connected to an electric motor and includes a semiconductor switching element which converts DC power on the DC side into AC power and a reverse connection diode which is connected in antiparallel with the semiconductor switching element. The smoothing capacitor is provided in the DC output of the diode converter. The resistor is connected in parallel with the smoothing capacitor. The current sensor detects a load current flowing between the inverter and the electric motor. The estimation unit calculates an estimation value of the DC voltage Vdc on the DC side on the basis of a current value I detected by the current sensor. The control unit controls the inverter so that the estimation value of the DC voltage Vdc on the DC side does not exceed a predetermined reference voltage during a period in which the electric motor is in a regenerative state.

A power converter according to an aspect of an embodiment includes: a diode converter; an inverter; a smoothing capacitor; a resistor; a current sensor; an estimation unit; and a control unit. The diode converter rectifies an alternating current from a power supply. The inverter is formed such that a DC side is connected to a DC output of the diode converter and an AC side is connected to an electric motor and includes a semiconductor switching element which converts DC power on the DC side into AC power and a reverse connection diode which is connected in antiparallel with the semiconductor switching element. The smoothing capacitor is provided in the DC output of the diode converter. The resistor is connected in parallel with the smoothing capacitor. The current sensor detects a load current flowing between the inverter and the electric motor. The estimation unit calculates an estimation value of the DC voltage Vdc on the DC side on the basis of a current value I detected by the current sensor. The control unit controls the inverter so that the estimation value of the DC voltage Vdc on the DC side does not exceed a predetermined reference voltage during a period in which the electric motor is in a regenerative state.

The electronic parking brake system according to an exemplary embodiment of the present disclosure includes a first ECU (electronic control unit) and a second ECU respectively connected to a plurality of motors for providing a driving force to a wheel to control the plurality of motors, wherein the second ECU includes a power reserve system for storing power supplied from a battery; a switch for switching to connect the plurality of motors to the first ECU or the second ECU based on the operating state of the first ECU; and a second MCU for identifying an operating state of the first ECU, controlling the switch to connect the plurality of motors from the first ECU to the second ECU based on the operating state being an inactive state, and controlling the plurality of motors through the power stored in the power reserve system.

The electronic parking brake system according to an exemplary embodiment of the present disclosure includes a first ECU (electronic control unit) and a second ECU respectively connected to a plurality of motors for providing a driving force to a wheel to control the plurality of motors, wherein the second ECU includes a power reserve system for storing power supplied from a battery; a switch for switching to connect the plurality of motors to the first ECU or the second ECU based on the operating state of the first ECU; and a second MCU for identifying an operating state of the first ECU, controlling the switch to connect the plurality of motors from the first ECU to the second ECU based on the operating state being an inactive state, and controlling the plurality of motors through the power stored in the power reserve system.

Systems and methods are provided for braking a translator of a linear multiphase electromagnetic machine. The system detects a fault event, and in response to detecting the fault event, causes the translator to brake using an electromagnetic technique. Braking includes causing the translator to stop reciprocating, by applying a force opposing an axial motion, which may occur within one cycle, or over many cycles. The fault event may include, for example, a fault associated with an encoder, a controller, an electrical component, a communications link, a phase, or a subsystem. The system includes a power electronics system configured to apply current to the phases. The system may use position information, current information, operating parameters, or a combination thereof to brake. Alternatively, the system need not use position information, current information, and operating parameters, and may brake the translator independent of such information.