Abstract: A voltage source converter having first and second DC terminals for connection to a DC network is provided. The voltage source converter includes at least one converter limb that extends between the first and second DC terminals and first and second limb portions that are separated by a respective AC terminal for connection to a corresponding phase of an AC network. Each limb portion includes a chain-link converter which is defined by a plurality of series-connected switching modules which operate in combination to provide a stepped variable voltage source. The voltage source converter includes a control apparatus configured to coordinate operation of the chain-link converters to cause an exchange of power between the DC and AC networks, evaluate the performance of one of the pluralities of series-connected switching modules, and modify the operation of the respective chain-link converter when the performance becomes degraded to a predetermined amount.

Abstract: In the field of high voltage direct current (HVDC) transmission, a voltage source converter comprises first and second DC terminals that are for connection to a DC network. The voltage source converter also includes at least one converter limb. The or each converter limb extends between the first and second DC terminals and includes first and second limb portions that are separated by a respective AC terminal for connection to a corresponding phase of an AC network. Each first limb portion extends between the first DC terminal and a corresponding AC terminal, and each second limb portion extends between the second DC terminal and the corresponding AC terminal. Each limb portion includes a respective chain-link converter which is defined by a plurality of series-connected switching modules which are operable in combination to provide a stepped variable voltage source.

Abstract: Provided is an apparatus, including a capacitor module having a plurality of connecting terminals and a plurality of switch elements. Each switch element has at least one switch terminal coupled to a corresponding connecting terminal, wherein the switch elements are configured for mutually exclusive operation via a control device.

Abstract: An electric coupler includes a body, a first electrical path through the body having a first resistance to electric current within a first frequency range and a second electrical path through the body having a second resistance to electric current within a second frequency range.

Abstract: A method for controlling a plurality of series connected switch modules each including at least two parallel connected electronic switches, the method includes the step of, in response to failure of any electronic switch of one or more switch modules, turning on any non-faulty electronic switch of one or more faulty switch modules when the electronic switches of other non-faculty switch modules are controlled to be turned on.

Abstract: A method for controlling a plurality of series connected switch modules each including at least two parallel connected electronic switches, the method includes the step of, in response to failure of any electronic switch of one or more switch modules, turning on any non-faulty electronic switch of one or more faulty switch modules when the electronic switches of other non-faculty switch modules are controlled to be turned on.

Abstract: A power conversion system includes a first converter effectively connected in series to a second converter. Each converter has a plurality of output levels. A phase-shifted transformer is coupled to the converters. The phase-shifted transformer has a delta-wound winding and an open star winding. The first converter is coupled to the open star winding and the second converter is coupled to the delta winding. The open star winding is configured for direct connection to either of a load or the open star winding of a second phase-shifted transformer, having a delta winding connected to a third converter. One or more DC voltage sources are each connected to the first and second converters by a respective DC link capacitor. Each DC voltage source is connected to a common power grid by an isolated multiphase transformer winding.

Abstract: An electric coupler includes a body, a first electrical path through the body having a first resistance to electric current within a first frequency range and a second electrical path through the body having a second resistance to electric current within a second frequency range.

Abstract: An electrical device comprises indicators used to indicate the operating status of the electrical device and/or the presence of hazardous voltage within the electrical device cabinet. The indicators comprise a lighting strip mounted on the outside of the device. The lighting strip can display different colors and/or flash according to the actual status of the electrical device.

Abstract: Provided is an apparatus, including a capacitor module having a plurality of connecting terminals and a plurality of switch elements. Each switch element has at least one switch terminal coupled to a corresponding connecting terminal, wherein the switch elements are configured for mutually exclusive operation via a control device.

Abstract: A magnetic component such as a transformer or inductor comprises one or more litz-wire windings and one or more metallic cooling tube windings. Each litz-wire winding is wound together with a corresponding single metallic cooling tube winding on a common bobbin to provide an indirectly-cooled magnetic component.

Abstract: A power conversion apparatus includes plural press-pack power semiconductor devices; plural thermal and electric conducting blocks provided among the plural press-pack power semiconductor devices; and plural bus bars provided among the plural press-pack power semiconductor devices and the plural thermal and electric conducting blocks to form a first column that is clamped under a predetermined mechanical force. The plural bus bars are directly pressed in the first or more columns for electrical connection, at least one of the press-pack power semiconductor devices is sandwiched between two thermal and electrical conducting blocks, and at least one of the bus bars is sandwiched between two thermal and electric conducting blocks. A method for assembling the power conversion apparatus is also provided. The apparatus and the method can provide optimum heat transfer for press-pack power semiconductor devices and minimum commutation loss and stress.

Abstract: A power conversion system includes a first converter effectively connected in series to a second converter. Each converter has a plurality of output levels. A phase-shifted transformer is coupled to the converters. The phase-shifted transformer has a delta-wound winding and an open star winding. The first converter is coupled to the open star winding and the second converter is coupled to the delta winding. The open star winding is configured for direct connection to either of a load or the open star winding of a second phase-shifted transformer, having a delta winding connected to a third converter. One or more DC voltage sources are each connected to the first and second converters by a respective DC link capacitor. Each DC voltage source is connected to a common power grid by an isolated multiphase transformer winding.

Abstract: A grid-side transformerless power conversion system configured to perform power conversion between a power grid and a load, the transformerless power conversion system includes a first converter, a first filter, and a second converter. The first converter is configured to convert first AC power provided from the power grid into DC power. The first converter includes a first converter module and a second converter module coupled to the first converter module to form a nested neutral point piloted topology. The first filter is coupled between the power grid and the first converter. The second converter is coupled to the first converter. The second converter is configured to convert the DC power into second AC power and provide the second AC power to the load.

Abstract: A method and cooling system that cools a power stack in a power conversion apparatus. The liquid cooling system includes a first cooling stage that includes first cooling components, wherein the first cooling components are connected to form parallel cooling branches; a mixing manifold configured to be fluidly connected to the parallel cooling branches so that cooling liquid streams from the parallel cooling branches are mixed in the mixing manifold; and a second cooling stage that includes second cooling components, and the second cooling stage is connected in series with the first cooling stage in terms of a cooling liquid that flows through the cooling system.

Abstract: A converter includes a first converter module and a second converter module coupled to the first converter module in a nested manner. Each of the first converter module and the second converter module includes a plurality of switch units. When the converter is operated to perform power conversion, at least two of the plurality of switch units is configured to be switched both in a complementary pattern and a non-complementary pattern.

Abstract: Systems and methods for suppressing resonances in power converters are provided. A power converter (100) includes an input stage (101) configured to receive alternating current (AC), an output stage (102) configured to output alternating current (AC), a first direct current (DC) bus (106) coupling the input stage (101) to the output stage (102), a second DC bus (108) coupling the input stage (101) to the output stage (102), a first capacitor leg (110) coupling the first DC bus (106) to the second DC bus (108) and a second capacitor leg (112) coupling the first DC bus (106) to the second DC bus (108). The first DC bus (106), the second DC bus (108), the first capacitor leg (110), and the second capacitor leg (112) form a current loop (130) having an effective inductance, and at least one resistor (140,142) configured to suppress a resonance of the power converter (100), wherein the resonance is based at least in part on the effective inductance of the current loop.

Abstract: A sub-sea power delivery system includes a plurality of modular power converter building blocks on each of the power source side and the sub-sea load side that are stacked and interconnected to meet site expansion requirements and electrical load topologies. The power delivery system comprises a system DC transmission link/bus, wherein the system DC link is configured to carry HVDC or MVDC power from an onshore utility or topside power source to multiple sub-sea load modules. The stacked modular power converter topology on the sub-sea side of the sub-sea power delivery system is symmetrical with the stacked modular power converter topology on the on-shore/top-side of the sub-sea power delivery system.

Abstract: An AC-AC Converter for an AC source which in one embodiment has a first rectifier section rectifying the AC source into a first pulsed DC link voltage signal and a high frequency modulating section coupled to the first pulsed DC link voltage signal and producing a high frequency AC voltage signal. A high frequency transformer is coupled to the high frequency AC voltage signal producing a transformed high frequency AC signal. There is a second rectifier section coupled to the transformed high frequency AC signal and producing a second pulsed DC voltage signal and an unfolder section coupled to the second pulsed DC voltage signal and producing an output AC signal.

Abstract: A method of controlling electrical power systems coupled to an electrical connection point includes obtaining carrier signals and fundamental waveforms from electrical power systems coupled to at least two renewable energy sources, generating pulse width modulation (PWM) signals using the carrier signals and the fundamental waveforms while interleaving carrier signals, fundamental waveforms, or a combination of carrier signals and fundamental waveforms of the electrical power systems, and driving grid side converters of the electrical power systems with the PWM signals.