A phasor measurement unit (PMU) of the present disclosure measures phasor, i.e., magnitude and phase angle of voltage and current, and related data from a specific location on the electrical gird synchronized to a common time source. The time-synchronized phasor is called a synchrophasor. In a system of the present disclosure, a plurality of PMUs transmit the synchrophasors and related data to a phasor data concentrator (PDC), which aggregates and time-aligns the data for real time and post analysis. The PMU of the present disclosure further functions as a power quality meter determining at least one of symmetrical components' phasor, frequency, rate of change of frequency, high-speed digital inputs, analog fundamental power and/or displacement power factor.

A phasor measurement unit (PMU) of the present disclosure measures phasor, i.e., magnitude and phase angle of voltage and current, and related data from a specific location on the electrical gird synchronized to a common time source. The time-synchronized phasor is called a synchrophasor. In a system of the present disclosure, a plurality of PMUs transmit the synchrophasors and related data to a phasor data concentrator (PDC), which aggregates and time-aligns the data for real time and post analysis. The PMU of the present disclosure further functions as a power quality meter determining at least one of symmetrical components' phasor, frequency, rate of change of frequency, high-speed digital inputs, analog fundamental power and/or displacement power factor.

The invention is related to a method for controlling an electrical installation from a remote control station, the electrical installation comprising a coupling network 5 powering one or more electrical loads 7, 8, a main switch 13 to connect a main power source 10 to the coupling network 5 and an auxiliary switch 23 to connect an auxiliary power source 20 to the coupling network 5.

The control method comprises a first step for synchronising the auxiliary power source 20 with the main power supply source 10 comprising a phase of measuring electric data relative to the main power supply source and to the auxiliary power source and a verification phase, from the remote control station, to ensure that the measured electric data relative to the main power supply source and the auxiliary power source is compatible, a step to send an order to close the auxiliary switch 23 from the remote control station, a step to send an order to open the main switch 13 from the remote control station and a checking step, from the remote control station, that the loads 7, 8 are correctly powered by the auxiliary power source.

A power converting device includes a DC-DC converting circuit, a DC-AC converting circuit, and an insulation detecting circuit. The DC-DC converting circuit is configured to convert a DC input voltage to a DC bus voltage. The DC-AC converting circuit is electrically coupled to the DC-DC converting circuit and configured to convert the DC bus voltage to an AC voltage. The insulation detecting circuit is electrically coupled between the DC-DC converting circuit and the DC-AC converting circuit. The insulation detecting circuit is configured to detect a ground impedance value of the power converting device according to the DC bus voltage.

An externally-controllable electrical power generating system for providing auxiliary or backup power to a load bus or device. The system may be used indoors, and generally includes a power source comprising a first DC output, an electrical storage unit comprising a DC input coupled to the first DC output of the power source, the electrical storage unit further comprising a second DC output. An inverter coupled to the second DC output receives power, the inverter having a first AC output that can be synchronized with an AC load bus or AC grid. The system includes a contactor connected between the first AC output and an AC load bus, and is controllable with an external controller operated by a utility or a managing entity, such that the external controller can enable the controller to connect or disconnect the contactor.

A power conditioning system (PCS) includes: a grid blackout determiner, a voltage controller, and a processor electrically connected to the grid blackout determiner and the voltage controller. The processor is configured to identify a state of a grid as a blackout state or an unstable state based on at least one of an amplitude or a frequency of a voltage of the grid that is detected by the grid blackout determiner, control the voltage controller to adjust, based on the identified state of the grid being the blackout state or the unstable state, load voltage input to the voltage controller to be equal to a command voltage, and adjust, based on the identified state of the grid being the blackout state or the unstable state, a first frequency of the detected voltage of the grid to a second frequency that is different from the first frequency.

A power conditioning system (PCS) includes: a grid blackout determiner, a voltage controller, and a processor electrically connected to the grid blackout determiner and the voltage controller. The processor is configured to identify a state of a grid as a blackout state or an unstable state based on at least one of an amplitude or a frequency of a voltage of the grid that is detected by the grid blackout determiner, control the voltage controller to adjust, based on the identified state of the grid being the blackout state or the unstable state, load voltage input to the voltage controller to be equal to a command voltage, and adjust, based on the identified state of the grid being the blackout state or the unstable state, a first frequency of the detected voltage of the grid to a second frequency that is different from the first frequency.

A method for connecting a power transformer, located between an inverter of a wind turbine and an electrical grid, to the electrical grid; the method comprises the steps gradually increasing a voltage at a primary side of the transformer from a low starting voltage to a target voltage equal or close to a nominal voltage of the transformer, by means of the inverter of the wind turbine or by means of an auxiliary inverter, thereby increasing the voltage at a secondary side of the transformer, wherein the gradually increasing of the voltage uses energy of an internal energy storage device, connecting the secondary side of the transformer to the electrical grid after predefined target conditions have been reached.

A method for connecting a power transformer, located between an inverter of a wind turbine and an electrical grid, to the electrical grid; the method comprises the steps gradually increasing a voltage at a primary side of the transformer from a low starting voltage to a target voltage equal or close to a nominal voltage of the transformer, by means of the inverter of the wind turbine or by means of an auxiliary inverter, thereby increasing the voltage at a secondary side of the transformer, wherein the gradually increasing of the voltage uses energy of an internal energy storage device, connecting the secondary side of the transformer to the electrical grid after predefined target conditions have been reached.

A method of synchronization comprises receiving, at a first generator set, data indicating a characteristic for a component of a voltage for a source, and receiving, at a second generator set, the data indicating the characteristic for the component of the voltage for the source. The method also includes calculating, by each of the first and second generator sets, a speed offset parameter and a voltage offset parameter based on the received data. The first and second generator sets are configured to receive the same data indicating the component and independently calculate the same speed offset parameter and voltage offset parameter. The method further includes controlling operation of the first and second generator sets based on the calculated speed offset and voltage offset parameters.