摘要:
Systems 10 and methods 300 for converting power are presented. The power conversion includes conducting load current through a first current path 92 of multiple current paths in a power conversion unit 12 using switches 60, diodes 74, or a combination thereof. The power conversion also includes blocking one or more additional current paths 94 of the multiple current paths in the power conversion unit 12 using one or more of the switches 60, one or more of the diodes 74, or a combination thereof. Furthermore, the power conversion includes reducing potential voltage stress on the one or more switches 60 by using one or more voltage stress reduction switches to reduce a voltage that is blocked by the one or more blocking switches or diodes 74 by connecting an end of each of the one or more switches 60 opposite to a blocking edge to an intermediate voltage node 84.
摘要:
A system 100 for commissioning a wind turbine 110 is provided. The system includes a test wind turbine 140, one or more additional wind turbines 160 coupled to the test wind turbine, and a control system 130. The control system 130 includes a first control module 132 for controlling the one or more additional wind turbines 160 to act as a power source and provide power to the test wind turbine 110. The control system 130 also includes a second control module 134 for controlling the one or more additional wind turbines 160 to act as a load for dissipating test power generated by the test wind turbine 110.
摘要:
High performance gate drives 200, 300 and methods 500 for driving semiconductor switching elements, such as insulated gate bipolar transistors (IGBTs), are provided. The gate drive 200, 300 can control the voltage applied to the gate of the IGBT 210, 220 to one or more intermediate voltages near the threshold voltage of the IGBT 210, 220 to control dv/dt of the collector-emitter voltage during and the di/dt of the collector current turn off. For instance, a voltage level between the turn on voltage and the turn off voltage can be applied for a first time period 506 to control dv/dt of the collector-emitter voltage and di/dt of the collector current during turn off. Another voltage level between the turn on voltage and the turn off voltage can be applied for a second time period 508 during reverse recovery of a freewheeling diode 215, 225 coupled in parallel with the IGBT 210, 220.
摘要:
The present subject matter is directed to apparatus 150 and methods for producing a variable frequency output waveform from a power converter 162 for use in a power generation system, such as a wind turbine power generation system 11. A voltage divider is employed to provide plural voltage levels to which a multi-level bridge circuit employing selectively activated switches (1 ... 14) in pairs of switches is coupled. The switches (1 ... 14) are operated in such a fashion as to produce a generally sinusoidal waveform that may be easily filtered by low cost filters 110 due to the plural voltage levels to produce a generally smooth sine wave from the converter 162. Such converters 162 may be used in various environments including in pairs in multi-phase power converters.
摘要:
A line side crowbar circuit (140) for an energy converter (105) is disclosed. In one aspect there is a power unit (100) that includes an energy converter (105); a transformer (130) configured to transfer electrical energy generated from the energy converter (105) to an electrical grid; and a crowbar (140) coupled to the energy converter (105) and the transformer (130) that is configured to prevent an overvoltage event from damaging electrical components associated with the energy converter (105) and the transformer (130).
摘要:
An electrical system for connecting a wind turbine 10 to a power grid 179 that includes: a frequency converter 103 that converts electric power produced by a generator 101 of the wind turbine 10 into electric power that is synchronized with the electric power of the power grid 179; a transformer 181 that steps up the voltage for connection to the power grid 179, the transformer 181 being disposed between the frequency converter 103 and a connection to the power grid 179; and a grid-side crowbar circuit 302; wherein the grid-side crowbar circuit 302 is configured to apply a short circuit to the electrical system upon the detection of a fault.
摘要:
An electric power converter 104 for a renewable power source 102 includes at least one alternating current (AC) conduit 176,178,180 coupled to an external AC power device 106 and at least one direct current (DC) conduit 114,116,118,132 coupled to an external DC power device 102. The converter also includes at least one immersion structure 222,322 defining at least one immersion cavity 226,326 therein and a plurality of semiconductor devices 200,300. The semiconductor devices include a substrate 204,304 positioned within the immersion cavity. The substrate defines a plurality of heat transfer surfaces 206,207,306,307 thereon. The semiconductor devices also include at least one semiconductor die 202,302 coupled to the substrate, the AC conduit, and the DC conduit. The converter further includes a liquid 228,328 at least partially filling the immersion cavity such that the semiconductor die is fully immersed in and in direct contact with the liquid. Heat 248,348 generated in the semiconductor device induces a phase change in the liquid.
摘要:
A method 200 for determining rotor position comprising sending a signal to a stator 102, receiving a first signal indicative of a first estimated stator inductance, and receiving a second signal indicative of a second estimated stator inductance. The method further includes, calculating a first rotor position angle using a function including the first estimated stator inductance and the second estimated stator inductance.
摘要:
A power converting apparatus and method providing for the addition of a fourth power connection wire to the neutral point of the normal three phase load circuit (105). This allows delivery of combined current from the center of the DC link voltage to load. The added control enables a third harmonic injection to flow and allows for increased power rating per peak amp handled by the conversion system. Limiting of faults to the positive half versus the negative half of the DC system allows for more robust behavior when encountering these fault conditions.