A converter (20) comprises: a first terminal and a second terminal (24,26), the first terminal (24,26) configured for connection to a first network, the second terminal (34) configured for connection to a second network (40); at least one switching module (44) arranged to interconnect the first terminal (24,26) and the second terminal (34), the or each switching module (44) including at least one module switching element (46) and at least one energy storage device (48), the or each module switching element (46) and the or each energy storage device (48) in the or each switching module (44) arranged to be combinable to selectively provide a voltage source, the or each switching module (44) switchable to control a transfer of power between the first and second networks (40); the or each switching module (44) including a discharge circuit, the or each discharge circuit including a discharge switching element (50) and a discharge resistor (52), the or each discharge switching element (50) switchable to switch the corresponding discharge resistor (52) into and out of the corresponding switching module (44); and a controller (54) configured to selectively control the switching of the or each discharge switching element (50) in: a normal mode to switch the corresponding discharge resistor (52) into the corresponding switching module (44) at a first switch-in voltage level of the or each corresponding energy storage device (48) during a normal operating state of the converter (20) so that a normal operating current flowing in the corresponding switching module (44) is divided between the corresponding discharge resistor (52) and the or each corresponding energy storage device (48) the or each first switch-in voltage level being lower than a voltage level corresponding to a maximum voltage capacity of the or each corresponding energy storage device (44); and a fault mode to switch the corresponding discharge resistor (52) into the corresponding switching module (44) at a second switch-in voltage level of the or each corresponding energy storage device (48) during a fault operating state of the converter (20) so that a fault current flowing in the corresponding switching module (44) is divided between the corresponding discharge resistor (52) and the or each corresponding energy storage device (48), wherein the or each second switch-in voltage level is lower than the corresponding first switch-in v

A power factor correction converter that outputs a DC output voltage from an AC input voltage, includes two channels each including a high-side switch and a low-side switch connected in cascade between a positive output terminal and a negative output terminal of the power factor correction converter and with a node between the high-side switch and the low-side switch; an inductor connected to a first terminal of the AC input voltage and the first node; a gate driver connected to the second high-side switch and the second low-side switch; a bootstrap circuit connected to the second node and the gate driver; wherein the second node is connected to a second terminal of the AC input voltage; and the bootstrap circuit is pre-charged at beginnings of negative half-cycles of the AC input voltage.

A converter assembly including a source connection system comprising a primary source connection, and at least one secondary source connection; a load connection system; a primary source converter including a primary rectifier connected electrically to the primary source connection, and having a boost topology, and a DC link connected electrically between the primary rectifier and the load connection system, the DC link including DC link capacitance; a secondary source converter, which is a direct-current converter having a boost topology, connected electrically between the at least one secondary source connection and the DC link; and a pre-charge converter adapted for pre-charging the DC link capacitance. The pre-charge converter includes a pre-charge direct-current converter having a step down topology.

For open loop phase pre-charge, an apparatus includes a Switching Mode Power Supply (SMPS) charging diode and a charge generator. The SMPS charging diode pre-charges an SMPS to a regulation set point from at least one phase of an Alternating Current (AC) voltage. The charge generator is powered by the pre-charged SMPS. In response to detecting the regulation set point iteratively, the charge generator detects a specified phase angle of the AC voltage. In response to the specified phase angle, the charge generator iteratively generates a charging voltage during positive voltage interval that charges a Direct Current (DC) bus capacitor to a target DC bus voltage within a charging time interval. At least a portion of the charge generator comprises one or more of hardware and executable code, the executable code stored on one or more computer readable storage media.

A control device includes a triac and a first diode that is series-connected between the triac and a first terminal of the device that is configured to be connected to a cathode gate of a thyristor. A second terminal of the control device is configured to be connected to an anode of the thyristor. The triac has a gate connected to a third terminal of the device that is configured to receive a control signal. The thyristor is a component part of one or more of a rectifying bridge circuit, an in-rush current limiting circuit or a solid-state relay circuit.

If sensed a connector as being connected to an inlet, an ECU performs pre-charging of a capacitor. When pre-charging of the capacitor is completed, the ECU closes a relay, and controls a U-phase boost chopper circuit to boost a voltage of the capacitor. The ECU closes relays if the voltage is boosted to a second target voltage.

In a switching power supply device, a control circuit controls a first thyristor, a second thyristor, and a switching element according to an input voltage. The control circuit maintains the first thyristor in an on state while maintaining the second thyristor and the switching element in an off state in a first period in which the absolute amplitude value is equal to or less than a first threshold value within the latter half of a first half-cycle of the input voltage at startup, and maintains the second thyristor in an on state while maintaining the first thyristor and the switching element in an off state in a second period in which the absolute amplitude value is equal to or less than a second threshold value within the latter half of a second half-cycle of the input voltage at startup. The second half-cycle is the half-cycle following the first half-cycle.

The invention relates to a power system with an electric circuit connected between a power grid and a power source. The electric circuit includes a main power converter having main input terminals connected to the power source 16 by a DC link and output terminals. The main power converter is controlled by a controller. The electric circuit includes a main transformer having a primary winding 8a and a secondary winding, the primary winding being connected to the output terminals of the main power converter. Main switchgear is connected between the secondary winding of the main transformer and the power grid. An auxiliary transformer has a primary winding connected to the power grid in parallel with the main switchgear and a secondary winding connected to the controller. A pre-charge circuit is connected between the auxiliary transformer and the DC link.

A semiconductor device includes a rectifier circuit that rectifies an AC input voltage, a zero-cross detection circuit that detects a zero-cross of the AC input voltage, a control circuit that turns on the rectifier circuit at a timing determined by the zero-cross detected by the zero-cross detection circuit and a predetermined phase angle, and the phase angle is set so that an output voltage of the rectifier circuit is gradually increased.

An improved AC power supply is described. The supply identifies the load through monitoring the current and voltage wave forms and phase relations with the AC Mains. The comparison is done in conditions where the power to the load is programmably varied through use of a control switch located in the line and neutral between the AC mains and the load. The program of controlling the switch is varied to optimize the ability to distinguish similar load types. The switch can be further used to control power to the load that varies according to a set of rules based upon the identity of the load. In a preferred embodiment, the design enables high efficiency with minimal components that may be fully integrated onto silicon.