3078 results about "Isolation transformer" patented technology

An impedance monitoring circuit for an electrosurgical generator is disclosed. The monitoring circuit includes an isolation transformer coupled to at least one of an active terminal and a return terminal of an electrosurgical generator, wherein the isolation transformer includes a primary winding coupled to a reference resistor and a secondary winding coupled to a load. The monitoring circuit also includes a driver configured to transmit a sensor signal to the reference resistor and the load, a primary converter coupled to the reference resistor and the load and configured to detect a primary converted signal as a function of the sensor signal passing through the reference resistor and the load. The monitoring circuit further includes a secondary converter coupled to the driver and configured to detect a secondary converted signal as a function of the sensor signal prior to passing through the reference resistor and the load and a controller configured to determine a fault condition based on the primary and secondary converted signals.

A planar transformer power supply for an electrosurgical device to minimize stray capacitance comprising a step down / step-up isolation transformer and circuitry to limit the effects of a short circuit in the output of the planar transformer power supply on the input to the planar transformer power supply to enhance power capacity at a low load impedance as low as from about 5 ohms to about 10 ohms and to operate at resonance at the output of the planar transformer power supply.

A power converter system advantageously employs a modular, bi-directionally symmetrical power converter assembly in a readily customizable configuration to interconnect a direct current power source to a three-phase alternating power grid. Connections external to the power converter assembly are selected to optimize the power converter system for a specific application, such as interconnecting a photovoltaic array to the three-phase electrical power grid. The electrical interconnections of various elements including isolation transformers, voltage sensors, and control switches are optimized to improve efficiency and reliability.

A method and system for enhancing computer peripheral safety is provided. In accordance with various aspects of the present invention, the exemplary method and system are configured to monitor and / or isolate alternating current (A.C.) supplies with and / or from any peripheral subsystems or devices. An exemplary method and system comprises an A.C. supply, a host computer system, and a peripheral subsystem or device connected to the host computer system, such as an ultrasound imaging and / or therapy peripheral, and an isolation subsystem configured for monitoring and / or isolating the A.C. supply from the peripheral subsystem or device. In accordance with an exemplary embodiment, an isolation subsystem comprises application software and associated modules and functions that when executed continuously monitors and / or polls the host computer's hardware and / or operating system for the presence of an isolated source, such as a battery, or an unisolated power source, such as through a battery charger and / or other connection path to the A.C. main supply. In accordance with other exemplary embodiments, an isolation subsystem can comprises a wireless or other safe / isolated electrical link for connecting a patient contact device, and / or a verification link or other verification mechanisms configured between an isolation transformer and host computer to monitor or observe usage to power the host computer and peripheral subsystem.

Stationary and on-board battery chargers, methods of charging batteries, electric-vehicle chargers, and vehicles with chargers, including electric vehicles and hybrid electric vehicles. Chargers may automatically charge at the correct battery voltage for various types of batteries. Chargers have variable AC power supplies controlled by digital controllers, isolation transformers, and rectifiers. Transformers may be foil-type, and may have copper foil. Power supplies may be variable-frequency generators and the controllers may control the frequency. Use of the variable frequency generator supply facilitates reduced component size and weight and better battery charging performance. Electric vehicle chargers may have card readers, and vehicles may have batteries and a charger. Methods of charging include identifying the battery type and gradually increasing the charging at different rates of increase while monitoring charging voltage, charging current, or both, until a current lid is reached. Charging may occur at constant current and then at constant voltage.

The electronic parking meter includes a microcontroller, an input interface, an output interface, communications devices and a power supply. The microcontroller receives instructions through the input interface from a user wishing to purchase parking time, controls the output interface to provide parking related messages or indications, and controls the electronic parking meter's communications with other devices through the communications devices for transmitting and receiving information and data. The power supply, which converts a battery pack voltage up to the operating voltage, may include an isolation transformer and a flyback switcher. The parking meter is maintained in a sleep mode as a default state, is placed in a schedule wake-up mode at a predetermined frequency for a predetermined short period of time to carry-out maintenance functions, and is only placed in an event wake-up mode for the time required to process major events, such as coin chute, card reader or communications port interrupts. The maintenance-free life of the parking meter is extended by using more of the energy that is available in standard battery packs and by decreasing energy consumed in the parking meter to carry out its functions through the three operating modes including the periodic schedule wake-up mode.

A method is disclosed for controlling single-phase DC / AC converters, along with a converter arrangement having at least two single-phase DC / AC converters. A controller is provided which can control the at least two single-phase DC / AC converters, and an isolation transformer, wherein outputs of the at least two single-phase DC / AC converters are cascade-connected with each other and an input of the isolation transformer. The controller is configured to control the at least two single-phase DC / AC converters to deliver power from their inputs to their outputs by turns.

The invention relates to a flexible direct current transmission converter valve steady-state high-power running testing device and a testing method. The testing device comprises an isolation transformer (TR1), a rectifier bridge (REC1) and a converter valve group. An alternating current input end of the rectifier bridge is connected with the isolation transformer. A direct current output end of the rectifier bridge is connected with the converter valve group. The testing device further comprises a BUCK-BOOST circuit which comprises an insulated gate bipolar translator (IGBT) module formed by an IGBT and an antiparallel diode, a resistor (R), a direct current bus support capacitor (C1) and a load electric reactor (L1). The resistor (R) and the IGBT module are connected in series and then connected with a direct current output end of rectifier bridge (REC1) in parallel. The direct current bus support capacitor (C1) is connected with two ends of a series branch circuit of the resistor (R) and the IGBT module in parallel and is connected with the converter valve group through the load electric reactor (L1). Through construction of a test platform which accords with the actual steady-state operation condition, the flexible direct current transmission converter valve steady-state high-power running testing device carries out steady-state power operation tests of a converter valve, carries out detection to current, voltage and temperature rising of components, and checks the correctness of design of the converter valve.