A motor drive apparatus includes a converter; an inverter for drive; a power storage device configured to supply DC power to a direct current link or to store DC power from the direct current link; a power consumption estimation unit configured to acquire a power consumption estimation value which is an estimation value of a total power consumption at a time point later, by a predetermined time, than a value at a present time point, the total power consumption being obtained as a sum of an output of the servomotor for drive, a winding loss in the servomotor for drive, a loss in the converter and a loss in the inverter for drive; and a power storage device control unit configured to control power supply and power storage of the power storage device in accordance with the power consumption estimation value.

Example electrical power systems include an output for supplying a DC output voltage to a load, a first power source connected with the output to supply DC power to the load, and a second power source connected with the output to supply DC power to the load. The electrical power system is configured to supply DC power to the load using only the first power source when a demand of the load is less than an output capacity of the first power source, and the second power source is configured to maintain an enabled on-state when only the first power source is supplying DC power to the load. Additional electrical power systems and methods are also disclosed.

A current-sharing control circuit, a power supply system and a current-sharing control method are disclosed. One embodiment of the power supply system comprises: multiple CV/CC power supplies connected in parallel to a load, whose nominal output voltages are the same and CV mode to CC mode switching points are adjustable; a current-sharing control circuit including an average load current sensor which senses a total current supplied to the load and outputs a first level linearly related to an average load current equal to the total current divided by the number of the working power supplies, and an output current sensor which senses an output current of each power supply and outputs a second level linearly related to the output current. The control circuit provides feedback signals related to the first level and the respective second levels to the power supplies to adjust their switching points to the average load current.

Systems, devices, computer-implemented methods, and/or computer program products that can facilitate an intelligent battery cell are addressed. In one example, a device can comprise: active battery cell material; and an internal circuit coupled to the active battery cell material and comprising: a circuit board; two alternating current (AC) power points; two isolated direct current (DC) power points; and a controller that can operate one or more switches on an H-bridge circuit to disconnect the device from a main battery in a bypass mode. In another example, a smart cell modulator can comprise: a set of smart battery cells; and a controller that can operate to selectively engage a subset of the smart battery cells to enable load sharing, distributed feedback control, circulate load across one or more smart battery cells of the set of smart battery cells to increase torque, and to enable speed requests.

Systems, devices, computer-implemented methods, and/or computer program products that can facilitate an intelligent battery cell are addressed. In one example, a device can comprise: active battery cell material; and an internal circuit coupled to the active battery cell material and comprising: a circuit board; two alternating current (AC) power points; two isolated direct current (DC) power points; and a controller that can operate one or more switches on an H-bridge circuit to disconnect the device from a main battery in a bypass mode. In another example, a smart cell modulator can comprise: a set of smart battery cells; and a controller that can operate to selectively engage a subset of the smart battery cells to enable load sharing, distributed feedback control, circulate load across one or more smart battery cells of the set of smart battery cells to increase torque, and to enable speed requests.

A method for stabilizing a DC voltage in a DC grid that includes a DC bus connected to a higher-order grid and to which an energy generating system and at least one load are connected. A variable electric grid output is exchanged between the DC bus and the higher-order grid in order to keep the DC voltage in the DC bus at a nominal voltage. The energy generating system includes a PV generator connected to the DC bus via a DC-to-DC converter and which exchanges an electric generator output with the DC bus. In a normal operating mode, the generator output is set to a normal operating output by the DC-to-DC converter on the basis of an MPP output of the PV generator. In a grid support mode, the generator output is set to a grid support output on the basis of the DC voltage in the DC bus in order to counteract a power imbalance between the electric power supplied in total to the DC bus and the power drawn in total from the DC bus.

A power supply system includes a plurality of power conversion devices connected in parallel with each other, a load state detector to detect an operating state of a load connected to the DC system, and a command generator to generate a distribution voltage command Vref Each of the power conversion devices includes a DC voltage controller to generate an output power command Pdc_ref based on a voltage of the DC system and the distribution voltage command Vref, and an AC/DC converter to convert AC power received from the main power source based on the output power command Pdc_ref and output the converted power to the DC system. The command generator generates the distribution voltage command Vref such that loss of the load connected to the DC system is reduced, based on a detection result of the load state detector.

In a power supply system, a first system includes a first power supply connected to a first load. A second system includes a second power supply connected to a second load. A connection path connects the systems. An intersystem switch is provided on the connection path. A control apparatus sets the intersystem switch to a closed state and sets a voltage of the first power supply to be higher than a voltage of the second power supply to be a first state in which power supply is performed from the first power supply to the loads. In response to a reverse-direction current from the second system to the first system flowing to the connection path in the first state, the control apparatus sets the intersystem switch to an open state to be a second state in which power supply is performed from the second power supply to the second load.

A plurality of generators redundantly supply power to AC motors via a main DC bus system having a pair of buses, each of which is connected to each generator by an active front end (AFE) inverter containing an insulated-gate bipolar transistor. Isolated DC/AC inverters are connected to the pair of main buses in pairs, respectively. Each pair of the isolated DC/AC inverters is connected to one of the AC motors with a filter of capacitors and inductors between each inverter and the motor. The AFE inverters and isolated DC/AC inverters galvanically isolate the main buses and enable load sharing among the generators.

The power supply device with multiple outputs includes two output ports, a power converting module with two power output ends, and two switching modules connected among the two power output ends and the two output ports. The output power from the two power output ends can be independently allocated to either one or two of the two second output ports. When one of the output ports requests for a demand power, the power supply device is able to determine which one or both of the power output ends to output power to the output port, reaching a better power allocation efficiency.