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.

An interface arrangement is configured to couple an alternating current, AC, power system with a direct current, DC, power system, or vice versa. The interface arrangement includes a plurality of series-connected converter modules. Each converter module includes at least one multi-level converter cell configured to provide a voltage contribution to at least a portion of an AC waveform for example based on voltage of the DC power system. Each converter module includes at least one converter valve, electrically connected to the multi-level converter cells and including at least two anti-parallel thyristors. The converter valves are switchable between conducting states with a selected current conduction direction and a non-conducting state so as to selectively control polarity of any voltage contribution provided by the at least one multi-level converter cell. The converter valves can also serve as fault protection, e.g. to divert overcurrents.

A bipolar DC power transmission scheme including first and second DC poles, each including a respective DC power transmission medium extending between first and second ends; a plurality of converters wherein each end of the transmission medium of each of the poles is operatively connected to at least one of the converters to form a rectifier and an inverter at opposite ends of the DC power transmission media; and a controller to operate at least one converter of one of the rectifier and inverter in a control mode and at least one converter of the other of the rectifier and inverter in a second control mode in response to a fault occurring on either of the poles. Additionally, the first control mode decreases and the second control mode increases the operating DC voltage of the or each corresponding converter from a normal operating voltage value.

The present disclosure provides an electric vehicle, a vehicle-mounted charger and a method for controlling the same. The method includes: obtaining a first total charging time and a second total charging time in a second manner, and a first total discharging time and a second total discharging time in the second manner; calculating a first total working time in the first manner and a second total working time in the second manner; obtaining a first predetermined charging time in the first manner, a second predetermined charging time in the second manner, a first predetermined discharging time in the first manner and a second predetermined discharging time in the second manner; selecting a manner according to the first and second total working time; and performing an alternate control according to the first and second predetermined charging time or according to the first and second predetermined discharging time.

The present disclosure provides an electric vehicle, a vehicle-mounted charger and a method for controlling the same. The method includes: obtaining a first total charging time and a second total charging time in a second manner, and a first total discharging time and a second total discharging time in the second manner; calculating a first total working time in the first manner and a second total working time in the second manner; obtaining a first predetermined charging time in the first manner, a second predetermined charging time in the second manner, a first predetermined discharging time in the first manner and a second predetermined discharging time in the second manner; selecting a manner according to the first and second total working time; and performing an alternate control according to the first and second predetermined charging time or according to the first and second predetermined discharging time.

A line commutated converter (LCC) for a high voltage direct current power converter, the LCC comprising at least one LCC bridge circuit for connection to at least one terminal of a DC system, each bridge circuit comprising a plurality of arms, each associated with a respective phase of an AC system, each arm comprising: an upper thyristor valve or valves, and lower thyristor valve or valves connected in series; an associated branch extending from between the upper and lower thyristors; and at least one thyristor-based capacitor module for each phase, each module comprising a plurality of module thyristors, the or each capacitor module operable to insert a main capacitor into the respective arm of the bridge circuit by firing at least one or more of said module thyristors.

The invention relates to the field of electrical engineering. An electricity supply system for a transport vehicle contains an electric network (1) with negative and positive wires, to which are connected an accumulator battery (2) and an electric starter (3); a capacitor bank (4); a bidirectional converter (5), which is connected between the capacitor bank and the electric network; a regulator (6); and a temperature sensor (11). Voltage from the capacitor bank is fed to an input (10) of the regulator, an additional input (12) of the regulator is connected to the temperature sensor, and outputs of the regulator are connected to control inputs (7, 8, 9) of the bidirectional converter, which bidirectional converter, in accordance with a signal at the control inputs, is capable of changing the parameters of its own volt-ampere characteristics at the outputs on the side of the electric network. The regulator is carried out in a way that the maximum current flowing from the bidirectional converter to the electric network is a decreasing function of the temperature-sensor temperature. The invention extends the service life of an electric starter and enhances the reliability of an electricity supply system.

A power transmission network, for interconnecting a variable power source and a AC electrical network including: a DC transmission link for power transmission between a network side converter and a source side converter; a AC transmission link for power transmission from the respective variable power source to a source side converter; a source side converter including: a DC connecting point operably connected to the respective transmission link; and an AC connecting point operably connected to the respective transmission link; a network side converter including: an AC connecting point for connection to the respective electrical network; and a DC connecting point operably connected to the respective transmission link; and a control system, where a network side converter is designated as a first converter, and the control system is configured to operate each first converter as a DC slack bus to vary a DC voltage at its DC connecting point.

In a power conversion device in a configuration in which a plurality of power converter cells has serially connected outputs and includes a converter and an inverter as components, when a load is light, the cells also operate with a light load, and efficiency is reduced. A power conversion device has a plurality of power converter cells. The outputs of the cells are connected in series. The device has a controller that controls the cells. The cells each have a converter that converts an externally inputted power supply voltage and generates a DC link voltage and an inverter that converts the DC link voltage into an alternating current voltage and outputs the current. The controller stops a converter in some of the cells depending on power supply electric power or load electric power. The inverter continues to operate using a link capacitor as a power supply.

A multi-pulse line-interphase transformer converter includes an electric part that includes magnetic components configured to be connected to a three-phase AC grid, and an electric part that includes a multi-phase voltage system configured to be connected to a common DC capacitor. The electric part splits each AC grid phase n times into two phases, resulting in a plurality of intermediate phases at an internal interface, each intermediate phase corresponding to a pulse of the multi-pulse line-interphase transformer converter. The intermediate phases are connected to the multi-phase voltage system. The multi-phase voltage system comprises bridges with actively controlled switches. The bridges are connected in parallel to the common DC capacitor.