摘要:
The present patent application relates to a method and equipment for eliminating harmonics based on two complementary techniques, namely the elimination of harmonics by selective harmonic elimination pulse-width modulation in conjunction with the multiple-wiring transformer. The association of these two resources is capable of reducing the harmonic distortion of currents to extremely low values, providing a truly unitary power factor. The technology is suitable for low and medium intensity alternating current - direct current and direct current - alternating current converters, which make interface with the electricity network and should have low harmonic distortion of the current because of the high power value involved, and also because of fragility of the electricity network (low power of short circuit at the coupling point).
摘要:
The invention concerns a reversible current rectifier, for connection to part of a polyphase network and to a continuous bus (2, 3) comprising a plurality of rectifier cells (200u, 200v, 200w, 300u, 300v, 300w), each rectifier cell including a rectifying device (4) and a one-way electronic switch (5) connected in anti-parallel with the rectifier device, the rectifying devices of different cells being arranged so as to form one rectifier. Each rectifier cell comprises means for controlling (600, 600'; 600'') the electronic switch (5) of the cell arranged to control the latter in closure after detecting a conduction of the rectifying device (4) of the cell so as to enable current to be returned to the network. The control means are arranged to receive a signal (601) external to the cell, for controlling the opening of the electronic switch (5), derived from another rectifier cell.
摘要:
A three-phase regenerative drive configured for operation from a single phase alternating current (AC) power source, the three-phase regenerative drive including a three-phase converter having inputs for connection to a single-phase AC source, the three-phase converter having three phase legs, a three-phase inverter for connection to a motor, the three phase inverter configured to provide three phase command signals to the motor, and a DC bus connected between the three-phase converter and the three-phase inverter. A first phase leg of the three-phase converter and a second phase leg of the three-phase converter are employed to direct current from the single-phase AC source to the DC Bus and a third phase leg of the three phase legs of the three-phase converter returns current to a return of the AC source.
摘要:
Approaches for controlling power supplied to an electric grid are disclosed. In embodiments, methods and systems control power supplied to an electric grid using an energy storage device. In an embodiment, a method receives an indication of power to be supplied to the electric grid, generates power from a power generator and adjusts, using the generated power, an energy level of the energy storage device to control power supplied to the grid in accordance with the received indication. In another embodiment, a system comprises a grid indication receiver for receiving an indication of power to be supplied to the electric grid; a power generator connected to the grid; an energy storage device coupled to the power generator; and a controller for adjusting, using the generated power from the generator, an energy level of the energy storage device to control power supplied to the grid in accordance with the received indication.
摘要:
Multilevel voltage arrangement having a transformer and a power converter or inverter comprising one or more common DC links connectable to a power source, said arrangement comprising one first set of H bridges being connected to said common DC link, wherein each of said H bridges comprises with at least two nodes connected to the ends of wirings at the primary side of a transfer, wherein control means are configured for controlling H bridges so as to achieve a multilevel voltage signal between the first node and the second node of said H bridges.