Ge Energy Power Conversion Technology Gmbh

General Electric Company

Martin Samuel Butcher

Allan David Crane

Lihua Hu

Christof Martin Sihler

Dong Dong

Ara Panosyan

Yan Pan

Richard Ian Stephens

Teng Long

Martin Richard Ingles

Benjamin Guy Salter

Ramasamy Anabarasu

Aravazhi Anabarasu

The invention relates to a power system that includes an electrical machine, (e.g., a motor or generator). The electrical machine has a stator with a stator winding connected to a power converter. The power system includes an assembly to reduce, and optionally eliminate, common mode currents between the electrical machine and the power converter. The assembly includes a stator frame connected to ground potential and an electrical insulator (e.g., a plurality of stator mounts) located between the stator frame and the stator.

Power systems

A power distribution system includes power converter systems electrically connected to a distribution bus which defines a point of common coupling. Each power converter system includes a power converter with semiconductor switching devices controlled using a pulse width modulation strategy with a switching frequency. A controller for each power converter system applies a spectrum analysis process to the respective power converter system that uses measured or derived zero sequence currents associated with the respective power converter system to determine the location of a ground fault within the power distribution system. Each controller applies a switching frequency process where the switching frequency of the power converter of at least one of the power converter systems is different from the switching frequency of the power converter of at least another one of the power converter systems during at least part of the time that the spectrum analysis process is applied.

Ground fault protection methods

A method of controlling a power system that includes an electrical machine, e.g., wind turbine generator, a power converter, a DC circuit and a dynamic braking system (DBS) having a braking circuit having a braking resistor and being connected in series to the DC circuit, is provided. The method includes operating the DBS and controlling operation of the electrical machine based on a prevailing temperature of the braking circuit, stopping the electrical machine and controlling the electrical machine to be restarted at its rated output power once the prevailing temperature of the braking resistor reaches or falls below a lower temperature threshold. The electrical machine may be restarted at a lower output power and after restarting, its output power can be increased based on a power starting profile as the braking resistor cools.

A power system for offshore application includes a plurality of power circuits. Each of the power circuit includes an alternating current (AC) bus which supplies power to an auxiliary load and is connected to a generator. The power circuit further includes a first direct current (DC) bus having a first DC voltage supplying power to a first load and a second DC bus having a second DC voltage supplying power to a second load. The power circuit also includes a first DC to DC converter coupled between the first DC bus and the second DC bus, wherein the first DC to DC converter is configured for bidirectional power flow and an AC to DC converter coupled between the AC bus and the first DC bus. The first DC bus of at least one power circuit is coupled to the second DC bus of at least another power circuit with a second DC to DC converter. The system also includes a controller configured to control the operation of the first DC to DC converter, second DC to DC converter and the AC to DC converter for regulating the first and second DC voltages. The controller is further configured to provide power to the second DC bus from the at least one AC to DC converter during a first operating state and from the first DC to DC converter during a second operating state.

Power system for offshore applications

A converter control arrangement () for regulating the output current of a dc source power converter () comprises a current regulator () for regulating the output current based on a comparison of an output current value (I) of the dc source power converter () with a desired target current value (I). When the output voltage value (V) of the dc source power converter () is within a normal operating voltage range between minimum and maximum voltage values (V, V) defined with respect to a voltage reference value (V) of the dc source power converter (), the converter control arrangement () controls the target current value (I) so that it is equal to a desired reference current value (I). When the output voltage value (V) is outside the normal operating voltage range, which typically indicates a fault condition, the converter control arrangement () modulates the reference current value (I) to provide a target current value (I) that is less than the reference current value (I).

Control arrangement and method for regulating the output current of a dc source power converter connected to a multi-source dc system

The present invention relates to a vacuum switch assembly for interrupting and isolating fault current. The vacuum switch assembly includes first and second dc lines that, in use, are electrically connected to the dc output terminals of a primary dc power source and a dc network. Each dc line includes at least one vacuum switch having contacts that are opened and closed under the control of a vacuum switch controller. A passive dc power supply unit is electrically connected to the first and second dc lines and includes a secondary dc power source that provides a substantially ripple-free sensing voltage. The vacuum switch controller is adapted to open the vacuum switch contacts when a fault condition (e.g. a fault current or other fault) or an operator request has been identified and when the current flowing between the vacuum switch contacts is below a chopping current associated with the vacuum switches.

Growing community of inventors

Rugby, United Kingdom

Martin Samuel Butcher