An electrical brake energy feedback system, including a rectifier and inverter circuit, an intermediate DC circuit, a first voltage detection circuit configured to detect voltages of positive and negative terminals of the intermediate DC circuit to obtain a first voltage signal, a bidirectional DC/DC conversion circuit and/or a regeneration control circuit, and an electrical energy flow control circuit for controlling operating states of the bidirectional DC/DC conversion circuit and/or the regeneration control circuit according to the first voltage signal. With this system, the electrical brake energy can be recovered to the greatest extent when the vehicle is running in different zones, and the electrical brake energy consumed by the brake resistor is as little as possible. Accordingly, the vehicle and the entire transportation system can be more energy-saving and environmentally friendly.

A motor vehicle has a motor performing power driving and regeneration. The motor includes an inverter, a first power storage device suppling energy to the motor, a power converter and a circuit. The converter has a voltage step down function during the power driving and a voltage step up function during the regeneration. The power converter, with the voltage step down function during the power driving, is connected in the circuit to the first power storage device. During the power driving of the motor, the power converter steps down an output voltage of the first power storage device to supply the energy from the first power storage device to the inverter. During the regeneration in the motor, the power converter steps up a DC voltage of the inverter to recover regenerated energy into the first power storage device.

A motor vehicle has a motor performing power driving and regeneration. The motor includes an inverter, a first power storage device suppling energy to the motor, a power converter and a circuit. The converter has a voltage step down function during the power driving and a voltage step up function during the regeneration. The power converter, with the voltage step down function during the power driving, is connected in the circuit to the first power storage device. During the power driving of the motor, the power converter steps down an output voltage of the first power storage device to supply the energy from the first power storage device to the inverter. During the regeneration in the motor, the power converter steps up a DC voltage of the inverter to recover regenerated energy into the first power storage device.

According to an embodiment, a power supply system for an electric motor car includes a first terminal, a second terminal, and a conversion unit. The first terminal is electrically connected to one of a power storage device and an overhead wire provided within a formation of electric motor cars. The second terminal is electrically connected to a lead wire together with a plurality of electric motors within the formation, a host power supply device, an external power supply device different from the host power supply device. The conversion unit receives first electric power supplied from the plurality of electric motors and the external power supply device via the second terminal and causes a direct current (DC) voltage to be generated at the first terminal according to a regenerative operation of the conversion unit to charge the power storage device in a first operation state and receives second electric power supplied from one of the power storage device and the overhead wire via the first terminal, converts a part of the second electric power into third electric power according to a powered operation of the conversion unit, and outputs the third electric power from the second terminal in a second operation state, thereby converting electric power.

A control device (2) for an inverter (1) which has a DC voltage input (3) and a power unit (5) with three half-bridges (11u, 11v, 11w) each formed by two power switching elements (13u, 13v, 13w, 15u, 15v, 15w), the control device (2) being arranged to driving the power switching elements (13u, 13v, 13w, 15u, 15v, 15w) in a normal operating mode for converting a DC voltage applied to the DC voltage input (3) into a polyphase AC current provided at an AC current output (4), wherein the control means (2) is adapted to evaluate a signal state of a signal (21) indicating a disconnection of a DC voltage source (9) from the DC voltage input (3) and to control the power switching elements (13u, 13v, 13w, 15u, 15v, 15w) in dependence on a result of the evaluation for alternately adopting a first switching pattern causing DC braking and a second switching pattern causing freewheeling.

In a power supply system, a plurality of voltage converters have chargeable/dischargeable batteries connected to the respective primary sides and have respective secondary sides connected in parallel to each other. For each of the voltage converters, a voltage transformation rate is set such that the current measured by a primary side current measuring instrument is maintained within a first range between the discharge current maximum value of the batteries connected to the primary sides and the charge current maximum value of the batteries.

A power supply system includes a first energy storage, a second energy storage, a power transmission circuit, and circuitry. The first energy storage outputs first output power to an electric load. The second energy storage outputs second output power to the electric load. The circuitry is configured to acquire a demand power to be supplied to the electric load. The circuitry is configured to acquire a remaining capacity value indicating remaining capacity in the second energy storage. The circuitry is configured to control the power transmission circuit to change a ratio of the first output power to the second output power to supply the demand power in accordance with the demand power and the remaining capacity value.

A power supply system includes a first energy storage, a second energy storage, a power transmission circuit, and circuitry. The first energy storage outputs first output power to an electric load. The second energy storage outputs second output power to the electric load. The circuitry is configured to acquire a demand power to be supplied to the electric load. The circuitry is configured to acquire a remaining capacity value indicating remaining capacity in the second energy storage. The circuitry is configured to control the power transmission circuit to change a ratio of the first output power to the second output power to supply the demand power in accordance with the demand power and the remaining capacity value.

A vehicle power supply system, a controlled unit is connected to a controllee power supply system that is one of a first power supply system and a second power supply system of the vehicle power supply system. A parameter acquiring unit is connected to a controller power supply system that is another one of the first power supply system and the second power supply system and configured to acquire a parameter indicating a sign of voltage change of the controllee power supply system. An operation setting unit is configured to predict the voltage change of the controllee power supply system in response to the sign indicated by the parameter and set a power supply state of the controlled unit indicating at least one of a number of drive pulses per unit time, a duty ratio, and a drive current so as to obtain a constant output from the controlled unit.

A vehicle power supply system, a controlled unit is connected to a controllee power supply system that is one of a first power supply system and a second power supply system of the vehicle power supply system. A parameter acquiring unit is connected to a controller power supply system that is another one of the first power supply system and the second power supply system and configured to acquire a parameter indicating a sign of voltage change of the controllee power supply system. An operation setting unit is configured to predict the voltage change of the controllee power supply system in response to the sign indicated by the parameter and set a power supply state of the controlled unit indicating at least one of a number of drive pulses per unit time, a duty ratio, and a drive current so as to obtain a constant output from the controlled unit.