A modular HVDC platform and a method for constructing the same are disclosed herein. The modular HVDC platform has a topside disposed on a structural jacket. The topside includes a first rectifier module, a second rectifier module, and a utility module. The first and second rectifier modules have equipment for converting AC power to DC power disposed therein. The utility module contains equipment for supporting the operations of the rectifier modules. Each of the rectifier modules and the utility modules can be fabricated and commissioned onshore prior to installation on the structural jacket at an offshore location.

The disclosure relates to a method and system for evaluating the stability of HVDC receiving end system and storage medium, which relates to the technical field of high voltage direct current transmission. The method includes: collecting voltage at a generator port, current at the generator port and rotational speed of the generator after eliminating fault; determining a corresponding relationship between the generator dynamic energy and the time according to the voltage at the generator port, the current at the generator port and the rotational speed of the generator; determining the attenuation intensity of the generator dynamic energy according to the corresponding relationship between the generator dynamic energy and the time; determining stability of the HVDC receiving end system according to the attenuation intensity of the generator dynamic energy.

Provided is a control method for a parallel MMC unit of a LCC-MMC hybrid cascade converter station. The control strategy includes: 1) numbering all MMC units connected in parallel in a MMC valve manifold; (2) for a MMC unit using a constant direct-current voltage control manner, calculating a direct-current instruction value of the MMC unit according to a direct-current measurement value; (3) for a MMC unit using a constant active power control manner, calculating an active power instruction value of the MMC unit according to the rated capacity of the MMC unit and a direct-current instruction value of a system rectifier station; (4) for the MMC unit using the constant direct-current voltage control manner, correcting a direct-current voltage instruction value of the MMC unit by using the direct-current instruction value and the direct-current measurement value, and controlling the MMC unit according to the corrected direct-current voltage instruction value.

Pulse power supply systems and methods are disclosed. A method includes providing earth-ground-referenced control circuitry and providing floating pulsed-power circuitry. The method also includes providing a DC offset voltage to the return port of the pulsed-power circuitry with a DC offset module and providing a peak voltage to the pulsed-power circuitry with a DC voltage source. Power is applied from a power source of the control circuitry to a driver of the pulsed-power circuitry via a galvanically-isolating power path and a trigger signal is applied from the control circuitry to the driver via a galvanically-isolated signal path to prompt the driver to produce a driver signal. A voltage pulse is produced between the output port and the return port by closing the switch with the driver signal to couple the peak voltage to the output port.

A first voltage source converter and converter station including such a first voltage source converter, as well as a method and computer program product for controlling the first voltage source converter are disclosed. The first voltage source converter has a DC side for connection to a DC system, has an AC side for connection to an AC system and is interconnected with an AC side of a second voltage source converter, which has a DC side connected to the DC system. The first voltage source converter includes a number of converter valve pairs, each being connected to a corresponding AC phase of the AC system and a control unit controlling the converter valves to generate at least one AC waveform and to reduce oscillations between the converters.

A converter station includes two line-commutated converters for energy transmission through a bipolar high voltage direct current transmission link. The two converters are electrically connected in an anti-parallel circuit to the same pole of the high-voltage direct current transmission link. One of the converters is operated as a rectifier in an AC grid and the other converter is operated as an inverter in the AC grid. A station reactive power exchanged by the converter station with the AC grid is controlled by real power stipulations for converter real powers which are exchanged between the converters and the AC grid. A method for operating the converter station is also provided.

The present invention discloses a power conversion system and a method for pre-charging DC-Bus capacitors therein. The power conversion system comprises a plurality of power modules, each including a power input end; a charging input end; a power output end; at least one power conversion unit, each of the power conversion unit including at least one DC-Bus capacitor and being electrically connected to the power input end and the power output end; and a pre-charging unit electrically connected to the charging input end for receiving direct current and electrically connected to the DC-Bus capacitor for pre-charging the DC-Bus capacitor. The power input ends of the plurality of power modules are connected in series and then electrically connected to an AC power source, and the power output ends of the plurality of power modules are connected in parallel.

A wind power converter device is provided. The wind power converter device includes grid side converters, generator side converters and a DC bus module. Each of the grid side converters includes grid side outputs electrically coupled to a grid and a first and a second DC inputs. Each two of the neighboring grid side converters are connected in series at the second and the first DC inputs. Each of the generator side converters includes generator side inputs electrically coupled to a generator device and a first and a second DC outputs. Each two of the neighboring generator side converters are coupled in series at the second and the first DC outputs. The DC bus module is electrically coupled between the grid side converters and the generator side converters.

A converter station has two line-commutated converters for energy transmission via a bipolar high voltage direct current transmission line. In a first operating mode of the converter station the two converters are electrically connected in an anti-parallel circuit to the same pole of the high voltage direct current transmission link and one of the converters is operated as a rectifier and the other converter is operated as an inverter in an network. In a second operating mode the two converters are connected to different poles of the high voltage direct current transmission link and both converters are operated as either rectifiers or inverters in the AC network. In both operating modes a station active power exchanged between the converter station and the AC network is controlled by active power specifications for converter active powers which are exchanged between the converters and the AC network.

Pulse power supply systems and methods are disclosed. A method includes providing earth-ground-referenced control circuitry and providing floating pulsed-power circuitry. The method also includes providing a DC offset voltage to the return port of the pulsed-power circuitry with a DC offset module and providing a peak voltage to the pulsed-power circuitry with a DC voltage source. Power is applied from a power source of the control circuitry to a driver of the pulsed-power circuitry via a galvanically-isolating power path and a trigger signal is applied from the control circuitry to the driver via a galvanically-isolated signal path to prompt the driver to produce a driver signal. A voltage pulse is produced between the output port and the return port by closing the switch with the driver signal to couple the peak voltage to the output port.