A multiphase converter topology is used for the transmission of electrical energy from an AC voltage input with m grid phase connections to a DC voltage output or vice versa. It has a power part with half-bridges for switching currents, an AC voltage filter between the power part and the AC voltage input, and DC voltage block(s) connected between the power part and the DC output. The AC voltage filter has alternating voltage filter stage(s) with m+1 input connections, m+1 output connections and a ground connection. The m grid phase connections are thereby connected in parallel to one another and form a first phase connection for the connection of a single-phase AC voltage. A neutral conductor connection of the AC voltage filter forms a neutral conductor connection of the AC voltage input and a second phase connection for the connection of the single-phase AC voltage.

There is provided a power supply apparatus for supplying power to an external electrical load, including a power transmission line or cable through which an alternating or direct current may flow, a power supply module, a control unit, an output terminal for connection to the external electrical load, and a converter. The power supply module includes an input terminal connected to the power transmission line or cable, and includes switching elements and energy storage device(s). The control unit controls the switching elements to selectively switch each energy storage device into circuit to direct a current flowing in the power transmission line or cable to flow through each energy storage device so as to store energy to form a power source. The converter draws power from the power source and supplies the drawn power to the output terminal.

A multiphase converter topology is used for the transmission of electrical energy from an AC voltage input with m grid phase connections to a DC voltage output or vice versa. It has a power part with half-bridges for switching currents, an AC voltage filter between the power part and the AC voltage input, and DC voltage block(s) connected between the power part and the DC output. The AC voltage filter has alternating voltage filter stage(s) with m+1 input connections, m+1 output connections and a ground connection. The m grid phase connections are thereby connected in parallel to one another and form a first phase connection for the connection of a single-phase AC voltage. A neutral conductor connection of the AC voltage filter forms a neutral conductor connection of the AC voltage input and a second phase connection for the connection of the single-phase AC voltage.

A multiphase converter topology is used for the transmission of electrical energy from an AC voltage input with m grid phase connections to a DC voltage output or vice versa. It has a power part with half-bridges for switching currents, an AC voltage filter between the power part and the AC voltage input, and DC voltage block(s) connected between the power part and the DC output. The AC voltage filter has alternating voltage filter stage(s) with m+1 input connections, m+1 output connections and a ground connection. The m grid phase connections are thereby connected in parallel to one another and form a first phase connection for the connection of a single-phase AC voltage. A neutral conductor connection of the AC voltage filter forms a neutral conductor connection of the AC voltage input and a second phase connection for the connection of the single-phase AC voltage.

A dynamic stability analysis and control method for a voltage sourced converter based high voltage direct current (VSC-HVDC) transmission system. The method includes the following steps: unlocking a converter station of the VSC-HVDC transmission system to make the VSC-HVDC transmission system run in a non-island control mode; extracting corresponding parameters of the VSC-HVDC transmission system, wherein the parameters include an effective voltage value U.sub.t0 of an AC system, an outgoing reactive power Q.sub.vsc0 of the VSC-HVDC transmission system, a gain k.sub.p of a phase-locked loop (PLL), and a proportional integral time constant k.sub.i of the PLL; calculating a short-circuit ratio (SCR), an unit value of U.sub.t0 and an unit value of Q.sub.vsc0; calculating a key stable component; checking the sign of the key stable component to determine the stability of the VSC-HVDC transmission system.

In the field of high voltage direct current (HVDC) power transmission networks there is a need for an improved power converter.

A power converter, for use in a HVDC power transmission network, comprises first and second DC terminals, for connection in use to a DC network and between which extends at least one converter limb. The or each converter limb includes first and second limb portions which are separated by an AC terminal, for connection in use to an AC network. Each limb portion includes a switching valve, and the power converter including a controller programmed to control switching of the switching valves to control the flow of a converter current (I.sub.max) through the power converter and thereby in-use transfer power between the power converter and the AC network. The power transferred between the power converter and the AC network has an active component and a reactive component. The controller is further programmed in use to: (i) prioritize to a first extent the transfer of reactive power between the power converter and the AC network during a first operating condition, when the AC voltage (V) of the AC network lies outside a desired operating range, by allowing up to a first amount of the converter current (I.sub.max) to be a reactive current; and (ii) prioritize to a second extent, less than the first extent, the transfer of reactive power between the power converter and the AC network during a second operating condition, when the AC voltage (V) of the AC network lies within the desired operating range, by limiting the amount of converter current (I.sub.max) that can be a reactive current to a second amount, less than the first amount, the second amount being determined according to a measured operating frequency of the AC network.

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.

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.

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.