A method and system are provided for transferring a load between a primary power source and a secondary power source. In accordance with the disclosure, a controller senses, via a sensor, an electrical signal providing power from the primary power source to the load. The controller also detects a non-conforming power event by determining that a parameter of the electrical signal is either more or less than a first threshold value. Responsive to the detection of the non-conforming power event, the controller determines a quantity of non-conforming power events that occur during a first time interval. The controller further can compares the determined quantity of non-conforming power events to a second threshold value. Responsive to the determined quantity of non-conforming power events being either greater or lesser than the second threshold value, the controller initiates a control signal, such as a control signal to initiate a load transfer.

A method and system are provided for transferring a load between a primary power source and a secondary power source. In accordance with the disclosure, a controller senses, via a sensor, an electrical signal providing power from the primary power source to the load. The controller also detects a non-conforming power event by determining that a parameter of the electrical signal is either more or less than a first threshold value. Responsive to the detection of the non-conforming power event, the controller determines a quantity of non-conforming power events that occur during a first time interval. The controller further can compares the determined quantity of non-conforming power events to a second threshold value. Responsive to the determined quantity of non-conforming power events being either greater or lesser than the second threshold value, the controller initiates a control signal, such as a control signal to initiate a load transfer.

A photovoltaic power generation system, having a photovoltaic panel, which has a direct current (DC) output and a micro-inverter with input terminals and output terminals. The input terminals are adapted for connection to the DC output. The micro-inverter is configured for converting an input DC power received at the input terminals to an output alternating current (AC) power at the output terminals. A bypass current path between the output terminals may be adapted for passing current produced externally to the micro-inverter. The micro-inverter is configured to output an alternating current voltage significantly less than a grid voltage.

The present disclosure relates to a recloser control that provides autosynchronization of a microgrid to an area electric power system (EPS). For example, a recloser control may include an output connector that is communicatively coupled to a recloser at a point of common coupling (PCC) between the area EPS and the microgrid. The recloser control may include a processor that acquires a first set of measurements indicating electrical characteristics of the area EPS and acquires a second set of measurements indicating electrical characteristics of the microgrid. The recloser control may send synchronization signals to a microgrid controller to synchronize the microgrid controller based on the first set of measurements and the second set of measurements.

The invention relates to a power system with an electric circuit connected between a power grid and a power source. The electric circuit includes a main power converter having main input terminals connected to the power source 16 by a DC link and output terminals. The main power converter is controlled by a controller. The electric circuit includes a main transformer having a primary winding 8a and a secondary winding, the primary winding being connected to the output terminals of the main power converter. Main switchgear is connected between the secondary winding of the main transformer and the power grid. An auxiliary transformer has a primary winding connected to the power grid in parallel with the main switchgear and a secondary winding connected to the controller. A pre-charge circuit is connected between the auxiliary transformer and the DC link.

The invention relates to a power system with an electric circuit connected between a power grid and a power source. The electric circuit includes a main power converter having main input terminals connected to the power source 16 by a DC link and output terminals. The main power converter is controlled by a controller. The electric circuit includes a main transformer having a primary winding 8a and a secondary winding, the primary winding being connected to the output terminals of the main power converter. Main switchgear is connected between the secondary winding of the main transformer and the power grid. An auxiliary transformer has a primary winding connected to the power grid in parallel with the main switchgear and a secondary winding connected to the controller. A pre-charge circuit is connected between the auxiliary transformer and the DC link.

The present disclosure is directed to self-synchronizing devices that can connect and self-synchronizes voltage, frequency and phase of two or more power sources. The disclosed embodiments enable a modular power system to serve as the primary or secondary source of power for applications requiring loads from a few kilowatts (kW) to the scale of megawatts (MW). The modular system is generalized to use either a single or multiple power generation sources at once, with the ability to connect and self-synchronize voltage, frequency, and phase of a variety of different types of power sources. Power control systems designed to function with self-synchronizing technology enable a modular power system to satisfy a wide variety of needs, simplifying the existing method of achieving synchronization and enabling new features of resiliency and expandability. The self-synchronization can be implemented into a wide variety of electronics including but not limited to inverters and generator controllers.

The present disclosure is directed to self-synchronizing devices that can connect and self-synchronizes voltage, frequency and phase of two or more power sources. The disclosed embodiments enable a modular power system to serve as the primary or secondary source of power for applications requiring loads from a few kilowatts (kW) to the scale of megawatts (MW). The modular system is generalized to use either a single or multiple power generation sources at once, with the ability to connect and self-synchronize voltage, frequency, and phase of a variety of different types of power sources. Power control systems designed to function with self-synchronizing technology enable a modular power system to satisfy a wide variety of needs, simplifying the existing method of achieving synchronization and enabling new features of resiliency and expandability. The self-synchronization can be implemented into a wide variety of electronics including but not limited to inverters and generator controllers.

A control unit repeats the series of processing of comparing a first phase representing a phase of the first reference sine wave and being a phase included in the first synchronization signal, with a second phase that is the phase of the second reference sine wave when the first synchronization signal is received when the communication unit receives the first synchronization signal from the other inverter generator, changing a phase change amount per unit time of the second reference sine wave in accordance with the comparison result, continuing to update the phase of the second reference sine wave so that the phase of the second reference sine wave changes with a phase change amount per unit time after the change with reference to the first phase until the next first synchronizing signal is received from the other inverter generator.

A control unit repeats the series of processing of comparing a first phase representing a phase of the first reference sine wave and being a phase included in the first synchronization signal, with a second phase that is the phase of the second reference sine wave when the first synchronization signal is received when the communication unit receives the first synchronization signal from the other inverter generator, changing a phase change amount per unit time of the second reference sine wave in accordance with the comparison result, continuing to update the phase of the second reference sine wave so that the phase of the second reference sine wave changes with a phase change amount per unit time after the change with reference to the first phase until the next first synchronizing signal is received from the other inverter generator.