2700 results about "Rectiformer" patented technology

Embodiments of a power provision system of the present invention generally include a transformer, a drive assembly, a motor control center, rectifiers, circuit breakers, and a cooling system, all of which are enclosed in a cabinet that is divided into a plurality of compartments that house various components and that is adapted and configured to be skid mounted on a trailer. In one embodiment, high voltage power is supplied to the power provision system, wherein it is stepped down to lower voltages by the transformer and the lower voltage power is utilized to drive a fracking pump motor via the drive assembly, as well as auxiliary equipment, such as the cooling system, via the motor control center. Embodiments of a method of using the power provision system are also provided.

Power conversion apparatus and methods are presented for providing electrical power to a grid or other load in which a synchronous machine is driven by a wind turbine or other prime mover to provide generator power to a switching type current source converter (CSC), with a current source rectifier (CSR) of the CSC being switched to provide d-axis control of the synchronous machine current based on grid power factor feedback, and with a current source inverter (CSI) of the CSC being switched to provide leading firing angle control and selective employment of dumping resists to dissipate excess generator energy in a fault mode when a grid voltage drops below a predetermined level.

A circuit for providing power factor correction in accordance with an embodiment of the present application may include a boost converter circuit and a control circuit receiving as inputs a rectified AC input voltage from a rectifier, a signal proportional to current through the boost inductor and the DC bus voltage across the capacitor of the boost converter. The control circuit provides a pulse width modulated signal to control the on time of a PFC switch. The control circuit further includes a voltage regulator and a current regulator. The current regulator includes a difference device operable to subtract a signal proportional to the inductor current from the current reference signal, a PI controller adapted to receive the output of the difference device and provide a first control signal, a feed forward device operable to receive the rectified AC input voltage and to provide a second control signal with a smaller dynamic range than the AC input voltage, and an adder operable to add the first control signal to the second control signal to provide a PWM reference signal for generating the pulse width modulated signal. A zero crossing detector and vector rotator may be provided to provide a clean sinusoidal reference to the current regulator. A partial PFC regulator may be provide to provide partial mode PFC if desired.

An LED driver circuit is disclosed. The top of a string of series connected LED segments is connected to the output of a rectifier, which in turn is connected to an AC source. The string is tapped at various locations, including the bottom of the string. Each segment can consists of any number of serial or parallel connected LEDs. Current control elements or regulators sink current at each tap and are sequentially turned on and off one at a time, tracking the rectified sine wave voltage. Voltage across each regulator and current when conducting is individually controllable. The regulators may control current in a multitude of ways, including a constant current, or a current dependent on voltage across the regulators including a resistor, or a combination. The driver is self-commutating, with the sequencing of the current control elements an inherent feature closely integrated with the current control elements and providing optimal performance over variable operating conditions.

A vehicle has an engine driving an alternator. The electrical energy supplied by the alternator feeds an electric traction motor, via a rectifier, an electric line, and an inverter. The electric traction motor is mechanically coupled to a wheel. A super-capacitor is connected to the electric line by means of a voltage-matching circuit. A unit for controlling the torque applied to the vehicle wheel manages the circulation of the electrical energy in the drivetrain so as always to discharge the super-capacitor as a priority, in order to be able to be ready to recover the energy at the next braking.

The invention discloses an emergency traction power supply system of an electric motor unit, which comprises a traction transformer used for reducing high voltage of a contact network, two rectifiers used for rectifying alternating current of secondary side windings of the traction transformer into voltage of middle direct current links, two inverters used for taking electricity from the middle direct current links and performing inversion into three-phase alternating current, a two-way auxiliary current transformer used for taking electricity from the middle direct current links and performing inversion into three-phase alternating current or taking electricity from a two-way charger and then performing boosting and rectification into the voltage of the middle direct current links, an auxiliary load used for obtaining the three-phase alternating current from the two-way auxiliary current transformer or the two-way charger by an auxiliary load power supply busbar, and the two-way charger used for obtaining the three-phase alternating current from a three-phase alternating current output side of the two-way auxiliary current transformer and performing voltage reduction and rectification on the three-phase alternating current into direct current to supply power to a lithium titanate battery and a direct current load which are connected with the two-way charger, or used for taking electricity from the lithium titanate battery and performing boosting and inversion into the three-phase alternating current to supply power to the auxiliary current transformer.

The invention relates to a LCL (Lower Control Unit) filtering controlled rectifying active damping control method of electric currents on a feedback variable current side, belonging to an active rectifying method of power electronics. The method comprises the following steps: a direct current voltage control unit is used for finishing the control on a direct current voltage and producing d-shaft active currents of an electric current control unit; a q-shaft current given is used for controlling reactive components of a rectifier; a soft phase locking unit is used for locking a power grid voltage phase position and realizing the synchronous rotational transformation of the power-grid voltage and sampling currents on the variable current side; the current given and a sampling actual value are fed into the electric current control unit; the output quantity of the electric current control unit is accumulated with the electric current on the variable current side which is fed back by usinga first-order high-pass filter to generate the given quantity of a voltage space vector unit; and finally, the voltage space vector unit generates six PWM (Pulse-Width Modulation) signals to finish the control on the rectifier. The method solves the stability problem of a LCL (Low Control Unit) filtering voltage type controlled rectifier and realizes the control of the rectifier on direct-currentvoltages and currents on line side under the condition that the electric current or voltage detection of a capacitor branch is not needed.

The invention discloses a three-phase bridge PWM rectifier switching tube open-circuit fault diagnosis method, and belongs to the field of a three-phase AC / DC converter. The invention aims to solve the problems of inaccurate, poor robustness and the like in multi-tube fault diagnosis in an existing diagnostic scheme. The method uses the characteristic that a fault phase grid-side current occurs to be a zero region when an open-circuit fault happens to any one of switching tubes in a three-phase bridge PWM rectifier, a current phase angle is extracted from a three-phase grid-side current, and fault detection and positioning are achieved according to the variation amount of the current phase angle and a power grid phase angle. The method disclosed by the invention can achieve effective diagnosis of open-circuit faults of both a single switching tube and a plurality of switching tubes in the three-phase bridge PWM rectifier, the software algorithm is simple, no additional hardware circuit is required, and the transient state of a system is highly robust.

The invention relates to an alternating current and direct current mixed traction power supply system with an ice melting function. The alternating current and direct current mixed traction power supply system comprises an alternating current power supply assembly, a direct current power supply assembly and a discharging coil, wherein the alternating current power supply assembly is used for realizing alternating current power supply, a traction transformer of the alternating current power supply assembly is connected into a traction power supply net through a first circuit breaker, the traction transformer outputs alternating current after the voltage reduction and is connected with the traction net through an alternating current feeder switch, the direct current power supply assembly is used for realizing direct current power supply, a rectifying transformer of the direct current power supply assembly is connected into a traction power supply net through a second circuit breaker, the rectifying transformer is subjected to voltage reduction and outputs direct current after being rectified via a rectifier, one path is connected with the traction net through the direct current feeder switch, the other path is connected with the traction net through a double-electrode high-voltage isolation switch, in addition, a high-voltage isolation switch used for realizing short circuit on a traction net uplink and a traction net downlink is arranged at the tail end of a section post line, and the traction net uplink and the traction net downlink form a ice melting loop; the discharging coil is arranged at the positive bus end of the output side of the direct current feeder switch and is provided with a high-voltage switch. The alternating current and direct current mixed traction power supply system has the advantages that the principles are simple, the function integrality is high, the operation is safe and reliable, and the like.