Abstract:
A housing (1) for a power semiconductor, providing a compartment (2) for installation of a power semiconductor (3), and comprising a first and a second terminal (4 A, 4B). The terminals (4A, 4B) are for connection of a power semiconductor (3) installed in the compartment, and for leading current to and from the compartment, The housing comprises a contact mechanism (6, 7, 8, 9, 10) for bypassing the compartment, the contact mechanism comprising at least one movable contact (7) arranged for electrically connecting the first and second terminal (4A, 4B), the at least one movable contact (7) being movable between a disconnected first position and a connected second position, in which second position the movable contact (7) connects the terminals (4A, 4B). The contact mechanism further comprising a bypass actuator (8) arranged inside the compartment and provided for transforming a pressure from an exploding semiconductor into motion, the bypass actuator (8) is operatively connected to the movable contact (7) and arranged to move the movable contact (7) from the first to the second position when subjected the pressure of an exploding semiconductor.
Abstract:
The invention relates to a method and a controller (8) for protection of a voltage source converter (1) comprising one or more phases (L1, L2, L3), each phase comprising one or more series- connected converter cells (2-1L1, 2-2L1,..., 2-nL1; 3-1L2, 3-2L2,..., 3-nL2 : 4-1L3, 4-2L3,..., 4-nL3). Each converter cell comprises a by-pass switch (S-1L1, S-2L1,..., S-nL1; S-1L2, S-2L2,..., S-nL2; S-1L3, S-2L3,..., S-nL3) for enabling by-pass thereof. The method comprises the steps of: detecting an over-voltage condition, and controlling simultaneously the by-pass switches of each converter cell so as to bypass the converter cells upon detection of such over- voltage condition.
Abstract:
An arrangement to determine a cell capacitor voltage value (U dc ) of a cell (10") of a multi-cell power converter comprises the cell (10") and a control unit (28). The cell (10") itself comprises four power electronic valves (1-4) interconnected as a full-bridge converter having a first and a second phase leg, where each phase leg comprises a series-connection of two (1, 3; 2, 4) of the four power electronic valves and where the connection point (6; 7) between the two power electronic valves of each phase leg is externally connectable, a cell capacitor (5) being connected in parallel to the first and the second phase legs, and four gate units (16-19), each being connected to a corresponding one of the power electronic valves (1-4) as well as to the control unit (28). Each of the four gate units (16-19) comprises a voltage measurement unit (24-27) adapted to take a continuous voltage measurement across the corresponding power electronic valve, and each of the four gate units (16-19) is adapted to transmit its continuous voltage measurement. The control unit (28) is adapted to receive from each of the four gate units (16-19) its continuous voltage measurement and to determine the cell capacitor voltage value (U dc ) based on at least one of these voltage measurements.
Abstract:
The invention relates to a rack 13 for a modular voltage source converter 11 comprising one or more converter modules 12 1 ..., 12n. The rack 13 comprises a housing 15 for accommodating the one or more converter modules 12 1 ..., 12 n , and an insulation device 10 comprising: a first electrically conducting layer 16, comprising a first connection means 19 for connection to an enclosure 14 housing the rack 13; a second electrically conducting layer 17, comprising a second connection means 20 for connection to one converter module 12 1 of the one or more converter modules 12 1 ,..., 12 n ; and an insulating layer 18 separating the first electrically conducting layer 16 and the second electrically conducting layer 17. The invention also relates to an insulation device 10.
Abstract:
It is presented a method of controlling a magnitude of an electrical parameter in a power system by means of a high voltage electron tube. The method comprises the steps of measuring (S1) the magnitude of the electrical parameter; generating (S2) a control signal based on the magnitude of the electrical parameter and on a reference magnitude of the electrical parameter;and switching (S3) the high voltage electron tube by means of the control signal such that the reference magnitude of the electrical parameter is essentially obtained. It is also presented a control arrangement and a power system.
Abstract:
Voltage source converter based on a chain-link cell topology, said converter comprising one or more phases (L1, L2, L3), each of said phases comprising one or more series- connected chain- link cell modules connected to each other, an output voltage of said voltage source converter is controlled by control signals applied to said cell modules. In case of failure of a chain- link cell module that module is controlled, by said control signals, such that zero output voltage is provided at its output voltage AC terminal.
Abstract:
A multilevel converter and a method for controlling a multilevel converter is provided. The multilevel converter is a single phase converter with one phase leg (1), or a three phase converter with three phase legs (1A-C), the phase legs of the three phase converter are interconnected in a star-configuration. The (1), or each (1A-C), phase leg comprises switching cells (11, 21),and each switching cell (11, 21) comprises semi-conductor switches (41, 51) arranged to selectively provide a connection to a corresponding energy storage element (42, 52). The converter also includes a controller (31), which is provided to monitor the DC voltage (VDC) of the energy storage elements (42, 52), and the controller (31) is provided to control the switching of each switching cell (11, 21). The phase leg (1) of the single phase converter, or each phase leg (1A-C) of the three phase converter, comprises two parallel branches (10, 20) of switching cells (11, 21), the branches (10, 20) being configured in a closed circuit. The method includes monitoring (105) the voltage levels of each of the energy storage elements, and balancing (107) the voltages of the energy storage elements, wherein the balancing includes circulating a current (104, 107) within the two branches of the (1), or each (1A-C), phase leg of the multilevel converter.
Abstract:
The invention concerns a voltage source converter comprising a number of voltage source converter cells and a method of controlling start up of a cell-based voltage source converter. The voltage source converter comprises a number of voltage source converter cells (CA) connected in cascade in at least two branches, where each voltage source converter cell comprises: a first and a second connection terminal (TE1A, TE2A) each providing a connection to a corresponding branch of the voltage source converter, a number of valve elements (CV1A, CV2A, CV3A, CV4A), an energy storage element (CIA) and a parallel circuit comprising a resistive element (RA) in parallel with a first switching element (SW1A) in order to limit the current running through the voltage source converter branch at start up.
Abstract:
A voltage source converter (22) having a plurality of cell modules (15, 31) connected in series, each cell module (15, 31) comprising a converter unit (6a, 6b) having an ac-side (Uac) and a dc-side (Udc), and the voltage source converter comprises a control unit (33, 70) adapted to control the converter units, where at least one of the cell modules (15) comprises a second redundant converter unit (6a, 6b) having an ac-side which is connected in parallel with the ac-side of the first converter unit and the control unit is configured to substantially synchronously control the first and the second converter units.
Abstract:
An arrangement for exchanging power, in shunt connection, with a three-phase electric power network (2) comprises on one hand for each said phase a reactive impedance element (31, 41, 51) and a Voltage Source Converter (32, 42, 52) connected in series with said element, and on the other a control unit (25) configured to control semiconductor devices of turn-off type of said converter for generating a voltage with a fundamental frequency being equal to the fundamental frequency of the voltage of the respective said phase and by that control a flow of reactive power between said arrangement and the respective phase of said electric power network. Each Voltage Sou rce Converter comprises a series connection of switching cells in the form of so-called H-bridges comprisi ng two switch ing elements connected in parallel and each having at least two semiconductor assemblies connected in series. Each switching cell further comprises at least one energy storing capacitor connected in parallel with said switching elements.