摘要:
A partial-voltage buck regulator controls a high-voltage bus to a full-bridge circuit such that overall switching losses are reduced and distributed. Low-voltage buck regulator devices are PWM-switched when high output voltage is needed, and high-voltage bridge devices are PWM-switched when low output voltage is needed. A variable input power supply, which may be operated in a high power factor mode, can adjust the input bus voltages to achieve optimum performance for a given magnetic resonance imaging sequence.
摘要:
A current control device is disclosed. The current control device includes control circuitry integrally arranged with a current path and at least one micro electromechanical system (MEMS) switch disposed in the current path. The current control device further includes a hybrid arcless limiting technology (HALT) circuit connected in parallel with the at least one MEMS switch facilitating arcless opening of the at least one MEMS switch, and a pulse assisted turn on (PATO) circuit connected in parallel with the at least one MEMS switch facilitating arcless closing of the at least one MEMS switch.
摘要:
An apparatus, such as a switch module, is provided. The apparatus can include an electromechanical switch structure configured to move between an open configuration and a fully-closed configuration (associated with a minimum characteristic resistance) over a characteristic time. A commutation circuit can be connected in parallel with the electromechanical switch structure, and can include a balanced diode bridge configured to suppress arc formation between contacts of the electromechanical switch structure and a pulse circuit including a pulse capacitor configured to form a pulse signal (in connection with a switching event of the electromechanical switch structure) for causing flow of a pulse current through the balanced diode bridge. The electromechanical switch structure and the balanced diode bridge can be disposed such that a total inductance associated with the commutation circuit is less than or equal to a product of the characteristic time and the minimum characteristic resistance.
摘要:
An apparatus, such as a switch module, is provided. The apparatus can include an electromechanical switch structure configured to move between an open configuration and a fully-closed configuration (associated with a minimum characteristic resistance) over a characteristic time. A commutation circuit can be connected in parallel with the electromechanical switch structure, and can include a balanced diode bridge configured to suppress arc formation between contacts of the electromechanical switch structure and a pulse circuit including a pulse capacitor configured to form a pulse signal (in connection with a switching event of the electromechanical switch structure) for causing flow of a pulse current through the balanced diode bridge. The electromechanical switch structure and the balanced diode bridge can be disposed such that a total inductance associated with the commutation circuit is less than or equal to a product of the characteristic time and the minimum characteristic resistance.
摘要:
A current control device is disclosed. The current control device includes control circuitry and a current path integrally arranged with the control circuitry. The current path includes a set of conduction interfaces and a micro electromechanical system (MEMS) switch disposed between the set of conduction interfaces. The set of conduction interfaces have geometry of a defined fuse terminal geometry and include a first interface disposed at one end of the current path and a second interface disposed at an opposite end of the current path. The MEMS switch is responsive to the control circuitry to facilitate the interruption of an electrical current passing through the current path.
摘要:
An optically powered MEMS gate driver includes a photovoltaic converter configured to receive a light signal from a light source and output a DC supply voltage for a MEMS gate driver in response thereto. The MEMS gate driver further includes a DC to DC converter electrically coupled to the photovoltaic converter and configured to output a line level DC voltage in response to the DC supply voltage. An electrical circuit, also included as a portion of the MEMS gate driver is electrically coupled to both the photovoltaic converter and the DC to DC converter is configured to receive the supply voltage and the line level voltage and to output a line level drive signal in response thereto. The optically powered MEMS gate driver is self-contained within a common EMI enclosure thus providing isolation between the gate driver and command signal electronics.
摘要:
A motor starter is provided. The motor starter includes micro-electromechanical system switching circuitry. The system may further include solid state switching circuitry coupled in a parallel circuit with the electromechanical switching circuitry, and a controller coupled to the electromechanical switching circuitry and the solid state switching circuitry. The controller may be configured to perform selective switching of a load current from a motor connected to the motor starter. The switching may be performed between the electromechanical switching circuitry and the solid state switching circuitry in response to a load current condition appropriate to an operational capability of a respective one of the switching circuitries.
摘要:
The present invention comprises MEMS enabled apparatus for the detection of arc-faults and the elimination of arc-flash conditions. The apparatus comprises an arc-flash detection component and a current limiting component. The current limiting component comprises a logic circuit in communication with the user interface, an MEMS protection circuit in communication with the logic circuit, and a switching circuit in communication with the MEMS protection circuit. The switching circuit comprises a plurality of micro-electromechanical system switching devices and a voltage limiting device, wherein the voltage limiting device is configured to prevent an over voltage event during a current limiting operation.
摘要:
A circuit for controlling operation of a load. In one example, a MEMS switch is positioned in the circuit to place the load in one of a conducting state or a nonconducting state. A piezoelectric transformer provides a relatively high voltage output signal or a relatively low voltage output signal to control movement of the switch between a closed position, placing the load in the conducting state, and an open position. The high voltage output signal includes a frequency component in the resonant frequency range of the transformer. Control circuitry provides an input voltage signal to the piezoelectric transformer to provide the high voltage output signal or the low voltage output signal at the output terminals of the piezoelectric transformer.
摘要:
A system is presented. The system includes a micro-electromechanical system switch. Further, the system includes a balanced diode bridge configured to suppress arc formation between contacts of the micro-electromechanical system switch. A pulse circuit is coupled to the balanced diode bridge to form a pulse signal in response to a fault condition. An energy-absorbing circuitry is coupled in a parallel circuit with the pulse circuit and is adapted to absorb electrical energy resulting from the fault condition without affecting a pulse signal formation by the pulse circuit.