An improved method for sharing power between multiple battery energy storage systems (BESS) connected to a common DC network having a nominal voltage wherein the current from each BESS is regulated based upon a voltage-current characteristic which defines an output current which increases linearly in a predetermined ratio as the measured system voltage decreases. The predetermined ratio is constant in respect of each BESS. The output current of each BESS varies based upon an external signal that varies with the state of charge of the BESS.

A decentralized voltage control method for a microgrid based on nonlinear state observers, comprising the steps of step 10), establishing a large-signal model of distributed generations, a connection network and impedance-type loads in the microgrid; step 20), establishing a Luenberger-like nonlinear state observer for each distributed generation; step 30), estimating the dynamic characteristics of other distributed generations in real time based on the local measured values of each distributed generation; and step 40), implementing the decentralized voltage control based on the control requirements of reactive power sharing and voltage restoration. The control method realizes the voltage control of microgrid based on the decentralized state observers, which does not rely on communication transmission or remote measurement and avoids the adverse effects of communication latency and data drop-out on the control performance.

A power system and method for performing a blackstart on a microgrid. The power system includes at least a first power converter and a second power converter. The first power converter comprises a first controller having a plurality of startup sequences for performing the blackstart. The second power converter is electrically coupled to the first power converter at a point of common coupling. During the blackstart, the first controller is configured to select and perform one of the plurality of startup sequences according to a point at which the second power converter is within the second power converter's startup sequence during the blackstart. The first controller selects the one of the plurality of startup sequences according to a microgrid voltage at the point of common coupling.

Energy supply system includes at least one local energy supply unit, at least one local energy consumption unit at least one local energy store, and a control unit which controls the energy consumption, by the at least one local energy consumption unit of the energy supply system, of the volume of energy generated by the at least one local energy generation unit, and controls the volume of energy stored in the at least one energy storage unit. After detecting at least one predictable future event which will influence the volume of energy generable by the energy consumption units and/or the volume of energy which can be drawn from the energy supply network and/or the volume of energy consumed by the energy consumption units, the control unit dynamically adapts an energy reserve, stored in the at least one local energy store, as a function of the detected events.

A method controls a micro-grid connected to a power distribution system. The method determines parameters of a model of dynamics of the micro-grid using measurements of power flow at a point of common coupling (PCC) of the micro-grid with the power distribution system. The model is exponentially stable on a voltage set-point at the PCC and the method determines, using the parameters of the model, an amount of reactive power required to maintain the voltage at the PCC asymptotically stable on the voltage set-point. Next, the method controls a generator of the micro-grid to produce the amount of reactive power.

Features and advantages of certain embodiments include a plurality of power supplies that work together to deliver power to a target circuit. In one embodiment, a downstream power supply provides a fast current delivery in response to load current transients and generates a feedback signal to control an upstream power supply so that the upstream and downstream power supplies work together to meet the current and voltage requirements of a target circuit across a wide range of loading conditions.

An inverter-based stand-alone microgrid control system using a time synchronization-based measurement unit, in which a converter controller configured to control a converter that determines a voltage and a phase of a point where a plurality of distributed power supply devices is interconnected. The system includes a time correction unit configured to provide a time corrected on the basis of time information received from a GPS; a signal comparison/generation unit configured to compare a sine wave generated according to a voltage magnitude and a phase reference signal with a harmonic carrier signal on the basis of the time provided by the time correction unit, and generate a PWM signal; and a switch operation control unit configured to apply the PWM signal from the signal comparison/generation unit to the converter, and operate a switch.

A control or management of a power router is more adequately performed when constructing a power network system in which power cells are asynchronously connected with each other. The power network system includes a first power router, a second power router and a management server. The first power router transmits power. The second power router receives the power from the first power router and the obtain information indicating the received power. The management server controls the power transmitted by the first power router base on the information indicating the received power.

Methods, systems, and controllers are described herein for controlling an electrical power system. A time-synchronized measurement of a phasor from one or more phasor measurement units is fed back to a feedback controller. Distributed energy resources of the electrical power system are controlled by the feedback controller using feedback control algorithms by sending, to distributed energy resources, a power setpoint derived from the time-synchronized measurement of the phasor.

An output end of a power converter is connected to a microgrid bus, and the microgrid bus is connected to an external power grid through a grid-tied switch. When detecting that a power grid fails, the power converter is in a first current source control mode. After a duration of the power grid failure reaches a first duration, the power converter switches from the first current source control mode to a first voltage source control mode. The first current source control mode is a current source failure ride-through control mode. The first voltage source control mode is a voltage source failure ride-through control mode. The first duration is less than a second duration, and the second duration is a time interval between a moment at which the power grid fails and a moment at which the grid-tied switch is turned off.