The present invention discloses a control system for monitoring and control of a micro-grid (100). The control system comprises a first controller for controlling of at least one of a power generation source and an electrical load, and a second controller (245) for controlling a rotating electrical machine (246). The rotating electrical machine (246) is electrically connectable to an electrical bus (205) of the micro-grid (100) for one of receiving electrical power and supplying electrical power. The second controller (245) is configured to coordinate with the first controller for operating the rotating electrical machine (246) by engaging the clutch (244) to couple the rotating electrical machine (246) to the prime mover (242), for supplying power.

A power management system for an elevator system. A power management system for an elevator system includes a power converter having three input terminals, two of the three input terminals coupled to a main power source for supplying single-phase AC power to the power management system, the power converter configured to convert the AC power from the main power source into DC power on a common DC bus, a secondary power source for supplying DC power to the common DC bus, a power inverter configured to invert the DC power on the common DC bus into AC output power for driving an electric motor of the elevator system, and a dynamic braking resistor which is coupled between a third input terminal among the three input terminals of the three-phase power converter and the common DC bus.

An electric power-regulating system includes an electric-load end, a power-supply end, a power regulator, a DC-bus device, a flywheel energy-storage device, a switch device and a controller. The flywheel energy-storage device connects the DC-bus device. The switch device is connected between the flywheel energy-storage device and the DC-bus device. The switch device provides at least one current-flow direction between the DC-bus device and the flywheel energy-storage device. The controller controls the power regulator and the flywheel energy-storage device. When a voltage of the DC-bus device exceeds a operation range, the controller selectively limits the current-flow direction of the switch device. Further, when a voltage-bias direction of the switch device and the current-flow direction are the same, the controller allows a current of the DC-bus device to flow into or out of the flywheel energy-storage device in the current-flow direction. In addition, an electric power-regulating method is also provided.

A motor drive system includes a power source unit configured to supply DC power to a DC link, a servo-amplifier for drive configured to convert the DC power in the DC link into AC power and supply the AC power as drive power to a servomotor for drive, a power storage device configured to store the DC power from the DC link or supply the DC power to the DC link, a power consumption calculation unit configured to calculate total power consumption as the sum of power consumed by the servomotor for drive, the servo-amplifier for drive and the power source unit, and a power storage device control unit configured to control power storage and power supply of the power storage device according to the total power consumption, wherein the power storage device control unit determines start and end of power storage or power supply, based on different thresholds.

A motor drive system includes a power source unit configured to supply DC power to a DC link, a servo-amplifier for drive configured to convert the DC power in the DC link into AC power and supply the AC power as drive power to a servomotor for drive, a power storage device configured to store the DC power from the DC link or supply the DC power to the DC link, a power consumption calculation unit configured to calculate total power consumption as the sum of power consumed by the servomotor for drive, the servo-amplifier for drive and the power source unit, and a power storage device control unit configured to control power storage and power supply of the power storage device according to the total power consumption, wherein the power storage device control unit determines start and end of power storage or power supply, based on different thresholds.

A power supply device for a molding machine with an intermediate circuit, which can be connected with at least one drive of the molding machine and is suitable for supplying the at least one drive with electrical energy; a supply module connected to the intermediate circuit; an energy storage device connected to the intermediate circuit; and a closed loop control device for closed loop controlling an energy content of the energy storage device. The energy storage device can be closed loop controlled by means of the closed loop control device so that the energy content of the energy storage device does not go outside a range, in which a power input and/or a power output of the energy storage device is essentially constant.

A power supply device for a molding machine with an intermediate circuit, which can be connected with at least one drive of the molding machine and is suitable for supplying the at least one drive with electrical energy; a supply module connected to the intermediate circuit; an energy storage device connected to the intermediate circuit; and a closed loop control device for closed loop controlling an energy content of the energy storage device. The energy storage device can be closed loop controlled by means of the closed loop control device so that the energy content of the energy storage device does not go outside a range, in which a power input and/or a power output of the energy storage device is essentially constant.

A motor drive system includes a converter configured to convert power between AC power in a power source and DC power in a DC link, an inverter for drive configured to convert power between the DC power in the DC link and AC power serving as drive power or regenerative power for a servomotor for drive, a motor control unit for drive configured to control the servomotor for drive connected to the inverter for drive, a power storage device configured to store the DC power from the DC link or to supply the DC power to the DC link, and a base holding energy change unit configured to change a base holding energy defined as a reference value of a holding energy of the power storage device, in accordance with the holding energy of the power storage device.

A motor drive system includes a converter configured to convert power between AC power in a power source and DC power in a DC link, an inverter for drive configured to convert power between the DC power in the DC link and AC power serving as drive power or regenerative power for a servomotor for drive, a motor control unit for drive configured to control the servomotor for drive connected to the inverter for drive, a power storage device configured to store the DC power from the DC link or to supply the DC power to the DC link, and a base holding energy change unit configured to change a base holding energy defined as a reference value of a holding energy of the power storage device, in accordance with the holding energy of the power storage device.

An emulator apparatus that emulates entities included in a microgrid is described herein. The emulator apparatus emulates a load with time-varying inductance/resistance or an energy storage device or combination of energy storage devices. The emulator apparatus is electrically coupled to a system or device that is desirably tested/maintained/designed. The emulator apparatus emulates a particular device, and response of the system of device to the emulated device is monitored for purposes of design, testing, or maintenance.