Systems, circuits, and methods are disclosed herein for charging (recharging) one or more batteries of an electric vehicle through an on-board charge shaping (or tuning) circuit. The charge shaping circuit may alter the charge signal received from a charging station and/or a regenerative charge signal from the vehicle motor based on one or more charge conditions at the battery. The shaped charge signal as controlled by the charge shaping circuit may improve one or more aspects of charging of the vehicle battery. The charge shaping circuit and/or a motor controller/inverter of the electric vehicle may include circuitry that is controllable to generate a shaped power signal in a similar manner as above, with or without the charge shaping circuit discussed above. In some implementations, one or more heat transfer systems may be included to transfer heat generated from the battery charging system to the battery.

In one embodiment, an EV charging system includes: a plurality of first converters to receive and convert grid power at a distribution grid voltage to at least one second voltage; a high frequency transformer coupled to the first converters to receive the at least one second voltage and output at least one high frequency AC voltage; and a plurality of port rectifiers coupled to a plurality of secondary windings of the high frequency transformer, each of the port rectifiers comprising a unidirectional AC-DC converter to receive and convert the at least one high frequency AC voltage to a DC voltage. At least some of the port rectifiers may be coupled in series to provide at least one of a charging current or a charging voltage to at least one dispenser to which at least one EV is to couple.

A wireless charging system includes a first power receiving device connected in parallel to a first battery and including a first sub resonant circuit having a first resonant frequency, a second power receiving device connected in parallel to a second battery and including a second sub resonant circuit having a second resonant frequency, and a power transmitting device. The power transmitting device is for determining a charging order between the first battery and the second battery. The power transmitting device wirelessly transmits first alternating current (AC) power having the first resonant frequency to the first sub resonant circuit when the first battery is selected according to the charging order and wirelessly transmits second AC power having the second resonant frequency to the second sub resonant circuit when the second battery is selected according to the charging order.

An electric power system includes a vehicle, a vehicle management server, an AC charging stand, a DC charging stand, and a charging stand management server. During AC charging and AC discharging, the AC charging stand is connected to the vehicle. An amount of charging power during AC charging and an amount of discharging power during AC discharging are calculated by the vehicle. The vehicle measures electric power before power conversion by an on-board charger, and calculates an amount of charging power and an amount of discharging power. An amount of charging power during DC charging and an amount of discharging power during DC discharging are calculated by the DC charging stand. The DC charging stand measures electric power before power conversion by a charger, and calculates an amount of charging power and an amount of discharging power.

An on-board charger is provided with a bulk capacitor adapted to couple to a vehicle traction battery and a relay for receiving electrical power from an external power supply and to pre-charge the bulk capacitor. A power factor correction (PFC) circuit is connected between the bulk capacitor and the relay. The PFC circuit includes a switch that is adjustable between an on-position and an off-position. The switch enables current flow from the relay to the bulk capacitor in the off-position. A snubber circuit is coupled to the switch to damp a transient voltage present at the switch during a transition from the on-position to the off-position. A processor is programmed to control the switch.

A vehicle charging apparatus is described herein, which may include a battery pack comprising a plurality of individual batteries, a power input port receiving electrical power at a first wattage, an AC-to-DC conversion circuit configured to provide DC power to charge groups of batteries in the plurality of individual batteries, a power conversion circuit configured to condition a DC output of at least one group of batteries to provide a charging current output to a vehicle via a coupling, and a processing circuit configured to control the power conversion circuit to provide the charging current at a second wattage greater than the first wattage. The first wattage may be actively or inherently limited to a level less than the second wattage in order to provide fast DC charging with a limited power input.

Various disclosed embodiments include illustrative controller units, direct current fast charging (DCFC) units, and methods. In an illustrative embodiment, a controller unit includes a controller and a memory configured to store computer-executable instructions. The computer-executable instructions are configured to cause the controller to determine status of a power electronics module (PEM) of a direct current fast charging (DCFC) unit, and instruct the PEM to control power quality of a three-phase alternating current (AC) grid power signal in response to the determined status being available.

Embodiments of the present application provide a charging and discharging device. The charging and discharging device includes an AC/DC converter, a first DC/DC converter, a second DC/DC converter and a control unit. The control unit is used to: receive a first charging request, the first charging request including a first charging voltage and a first charging current; set output power of the first DC/DC converter based on the first charging voltage and the first charging current; turn on the second DC/DC converter if an SOC of the energy storage unit is greater than a first threshold to charge the battery by the energy storage unit; and adjust output power of the second DC/DC converter, so as to enable a voltage difference between a bus voltage and a bus balance voltage of the charging and discharging device to be less than or equal to a preset value.

Embodiments of the present application provide a charging/discharging apparatus, a method for charging a battery and a charging/discharging system, the charging-and-discharging apparatus including a bidirectional AC/DC converter, a first DC/DC converter, and a control unit, where the first DC/DC converter is a bidirectional DC/DC converter; and where the control unit is configured to: receive a first charging current sent by a BMS of a battery, control the bidirectional AC/DC converter and the first DC/DC converter according to the first charging current to charge the battery through an AC power; receive a first discharging current sent by the BMS and discharging a power of the battery according to the first discharging current; and receiving a second charging current sent by the BMS and control the bidirectional AC/DC converter and the first DC/DC converter according to the second charging current to charge the battery through the AC power.

Embodiments of the application provide a method for charging battery a charging and discharging device, which can ensure the safety performance of the battery. The charging and discharging device includes a first DC/DC converter, a unidirectional AC/DC converter and a control unit, where the first DC/DC converter is a unidirectional DC/DC converter, and the control unit is configured to: receive a first charging current and control the unidirectional AC/DC converter and the first DC/DC converter to charge a battery through an AC power source based on the first charging current; receive a first discharging current, and control the battery to release power based on the first discharging current; and receive a second charging current, and control the unidirectional AC/DC converter and the first DC/DC converter to charge the battery through the AC power source based on the second charging current.