A power converter includes: a plurality of semiconductor devices; a heat receiving plate; and a first partition member. The semiconductor devices constitute a power conversion unit. The heat receiving plate includes a first surface supporting the semiconductor devices. The first partition member is fixed to the heat receiving plate and partitions the semiconductor devices.

A power converter includes: a plurality of semiconductor devices; a heat receiving plate; and a first partition member. The semiconductor devices constitute a power conversion unit. The heat receiving plate includes a first surface supporting the semiconductor devices. The first partition member is fixed to the heat receiving plate and partitions the semiconductor devices.

A controller of an embodiment includes a limiter receiving an active current command initial value, limiting a maximum value of the active current command initial value with a predetermined value, and outputting a first value; a circuit to calculate a reactive current command initial value; a calculator to calculate a reactive current command adjustment value; a unit receiving the first value as an input, and calculating a reactive current upper limit value such that a composite value of the first value and the reactive current upper limit value is equal to or smaller than an input current maximum value; and a limiter to output the reactive current command adjustment value or the reactive current upper limit value, whichever is smaller. The predetermined value is a value to set the reactive current upper limit value to a value larger than zero and smaller than the input current maximum value.

A controller of an embodiment includes a limiter receiving an active current command initial value, limiting a maximum value of the active current command initial value with a predetermined value, and outputting a first value; a circuit to calculate a reactive current command initial value; a calculator to calculate a reactive current command adjustment value; a unit receiving the first value as an input, and calculating a reactive current upper limit value such that a composite value of the first value and the reactive current upper limit value is equal to or smaller than an input current maximum value; and a limiter to output the reactive current command adjustment value or the reactive current upper limit value, whichever is smaller. The predetermined value is a value to set the reactive current upper limit value to a value larger than zero and smaller than the input current maximum value.

For starting an AC electric motor of a mining vehicle, it is first accelerated to a first speed with a second AC voltage provided by an onboard battery-powered inverter of the mining vehicle. A phase of a first AC voltage taken from an external grid is compared to a phase of said second AC voltage. If the phase difference between the first and second AC voltages is larger than a predetermined limit, the speed at which said inverter rotates said AC electric motor is changed. If the difference between the phases of the first and second AC voltages is smaller than the predetermined limit, a change is made from rotating the AC electric motor with the second AC voltage to rotating the AC electric motor with the first AC voltage.

A power conversion system includes a transformer, a power conversion device for travel, a power conversion device for auxiliary power sources, an electrical storage device, and an auxiliary device. The power conversion device for travel converts AC power into power for travel and supplies it to a travel motor. The power conversion device for auxiliary power sources includes an AC to DC conversion unit which converts AC power into DC power, a power conversion unit for AC loads which converts the DC power into AC power and supplies it to an AC load, and a power conversion unit for DC loads which converts DC power to DC power and supplies it to a DC load. The electrical storage device is connected to power lines connecting DC power output terminals of the AC to DC conversion unit and DC power input terminals of both the power conversion units for AC and DC loads. The auxiliary device is connected to power lines connecting the power conversion device for auxiliary power sources and the electrical storage device and operates with power supplied from the electrical storage device.

A power conversion system includes a transformer, a power conversion device for travel, a power conversion device for auxiliary power sources, and an electrical storage device. The power conversion device for auxiliary power sources includes a first AC to DC conversion unit, a power conversion unit for AC loads, and a power conversion unit for DC loads. The power conversion unit for AC loads converts DC power into AC power and supplies it to an AC load. The power conversion unit for DC loads converts DC power produced through conversion by the first AC to DC conversion unit into DC power and supplies it to a DC load. The electrical storage device is connected to power lines connecting DC power output terminals of the first AC to DC conversion unit and DC power input terminals of both the power conversion units for AC and DC loads. When power supplied from a tertiary winding of the transformer to the first AC to DC conversion unit is reduced, the electrical storage device discharges power corresponding to the power reduction.

A converter system for electrically driving a vehicle, including a grid-side converter, a DC link with at least a first and second potential conductors, and a motor-side converter. The motor-side converter allows a bidirectional flow of energy. The grid-side converter has a single phase on the input side and is connected to a supply grid. The grid-side converter is unidirectional and allows a flow of energy from the supply grid into the DC link. The DC link connects the grid-side converter to the motor-side converter and has a first electrical energy storage between the first and second potential conductors. The electrical energy storage is connected to the DC link via an electrical connection. The flow of energy from the DC link into the further electrical energy storage and the flow of energy from the further electrical energy storage into the DC link is able to be controlled.

A converter system for electrically driving a vehicle, including a grid-side converter, a DC link with at least a first and second potential conductors, and a motor-side converter. The motor-side converter allows a bidirectional flow of energy. The grid-side converter has a single phase on the input side and is connected to a supply grid. The grid-side converter is unidirectional and allows a flow of energy from the supply grid into the DC link. The DC link connects the grid-side converter to the motor-side converter and has a first electrical energy storage between the first and second potential conductors. The electrical energy storage is connected to the DC link via an electrical connection. The flow of energy from the DC link into the further electrical energy storage and the flow of energy from the further electrical energy storage into the DC link is able to be controlled.

A power conversion controller for electric train in one aspect of the present disclosure includes an active current command value generator, an overhead line voltage detector, an initial value calculator, an adjustment value calculator, an upper limit value setter, and an output limiter. The output limiter outputs a reactive current command adjustment value calculated by the adjustment value calculator as a reactive current command value when the reactive current command adjustment value is equal to or lower than an upper limit value set by the upper limit value setter, and outputs the upper limit value as the reactive current command value when the reactive current command adjustment value exceeds the upper limit value.