Local area network power management device
The power management device with a central controller and grid-forming inverter addresses the challenge of uninterrupted power supply and efficient energy distribution by switching to islanding mode, utilizing domestic batteries and electric vehicles for critical load support and energy balancing.
Patent Information
- Authority / Receiving Office
- FR · FR
- Patent Type
- Applications
- Current Assignee / Owner
- NW JOULES
- Filing Date
- 2024-11-20
- Publication Date
- 2026-05-22
AI Technical Summary
Existing power management systems fail to provide uninterrupted power supply to critical loads during grid disturbances and do not efficiently manage energy distribution between critical and non-critical loads, nor do they facilitate efficient energy storage and retrieval from domestic batteries and electric vehicles.
A power management device with a central controller, islanding switch, and grid-forming inverter that switches to islanding mode to supply critical loads from domestic batteries and electric vehicle batteries, allowing energy balancing and load restoration, with features like voltage sensing and grid-forming capabilities.
Ensures uninterrupted power supply to critical loads, manages energy distribution efficiently, and enables energy storage and retrieval from domestic batteries and electric vehicles, enhancing grid resilience and load management.
Abstract
Description
- a first power supply interface (5a) for critical local network loads; - an islanding switch (7) of which a first terminal (7a) is connected to the network input (3); - a first voltage sensor (8), located between the network input (3) and the islanding switch (7); - a central controller (10), configured to receive measurements from said first voltage sensor (8) and open the islanding switch (7) when the measured voltage is below an islanding threshold for a first predetermined period; - a network forming inverter (14), said network forming inverter (14) comprising a first AC terminal (AC1) connected to the second terminal (7b) of said islanding switch, a DC terminal, and a backup AC terminal (AC2) connected to the first power interface (5a), said network forming inverter (14) being configured to provide, at the backup AC terminal (AC2), an uninterruptible supply to the critical loads of the local network; - at least one domestic battery (11) connected to the direct current (DC) terminal of the grid forming inverter (14), said domestic battery (11) having a power rating strictly less than 50 kW and being suitable for: to supply at least the critical loads of the local network, for a second predetermined duration longer than the first predetermined duration, and . reinject electricity onto the network input (3) destined for the public network; - at least one bidirectional electric vehicle (13) charging station (12) connected to the first AC terminal (AC1) of the grid-forming inverter (14), so that the household battery (11) can be used to charge the electric vehicle (13) and, when an electric vehicle (13) is connected with sufficient charge, such that an electric vehicle battery can be used to recharge the home battery (11); the power management device being able to operate in an islanding mode in which the home battery (11) and / or the electric vehicle battery (13) supply the power interface (5). [Claim 2] Management device (1) according to claim 1, characterized in that the central controller (10) is configured to be able to control the power management device of a local network (1) in a balancing mode in which the islanding switch (7) is closed and the home battery (11) and / or the electric vehicle battery (13) are used to perform injection or withdrawal from the network inlet (3).[Claim 3] Management device (1) according to any one of claims 1 or 2, characterized in that the central controller (10) is configured to receive a measurement of the power of the electrical signal measured at the network input (3), and to be able to control the management device (1) in an overload absorption mode in which, when the power delivered by the network is less than the needs of the local network, the home battery (11) and / or the battery of the electric vehicle (13) are used to supply the local network in addition to the public network.[Claim 4] A management device (1) according to any one of claims 1 to 3, characterized in that at least one of the loads enabling local network restoration in the event of an outage, including the central controller (10), and the auxiliaries (18) of the home battery (11) and / or the charging station (12), is connected to the backup AC terminal (AC2), so as not to require an uninterruptible power supply for at least one of these components. [Claim 5] A management device (1) according to any one of claims 1 to 4, characterized in that the central controller (10) is configured to close at least one ground-neutral switch (19) enabling the neutral of the second terminal (7b) of the islanding switch (7) to be grounded when the islanding switch (7) is open. [Claim 6] Management device (1) according to any one of claims 1 to 5, characterized in that the first predetermined duration is less than 10 seconds.[Claim 7] Management device (1) according to any one of claims 1 to 6, characterized in that the power of the domestic battery (11) is between 5 and 20 kW. [Claim 8] Management device (1) according to any one of claims 1 to 7, characterized in that it comprises an interface (15) to a photovoltaic installation (16), said interface (15) being connected to the direct current (DC) terminal of the grid-forming inverter (14). [Claim 9] Management device (1) according to any one of claims 1 to 8, characterized in that it comprises a second power supply interface (5b) for non-critical loads from the local grid, connected to the second terminal (7b) of the islanding switch (7), and in that the central controller (10) is configured so that in the event of opening of the islanding switch (7),The central controller (10) commands the grid forming inverter (14) to supply non-critical local grid loads via the first AC terminal (AC1) of the grid forming inverter (14). [Claim 10] A method of using a management device according to any one of claims 1 to 9, comprising the following steps: - supplying critical local grid loads from the public electricity grid; - measuring by the first voltage sensor (8) a voltage below said islanding threshold, indicating disturbances on the public electricity grid, leading to the activation of the uninterruptible power supply function of the grid forming inverter, in order to prevent an interruption in the supply of critical loads; - measuring by the first voltage sensor (8) a voltage below said islanding threshold for a first predetermined period; - opening the islanding switch (7),and switching of the network forming inverter (14) from a network following mode to a network forming mode; - regulation of the voltage on the local network by the network forming inverter (14), using measurements from a second voltage sensor (20) located at the second terminal (7b) of the islanding switch (7),
Claims
- measurement by the first voltage sensor of a voltage above a connection threshold for a third predetermined duration, resulting in the closure of the islanding switch (7), - supply of critical loads of the local network by the public electricity network.
11. A method of use according to claim 10, further comprising, just before the step of closing the islanding switch (7), a step of synchronizing the voltage and / or frequency of the network inverter (14) to the voltage and / or frequency of the public electricity network.
12. Method of using according to any one of claims 10 to 11 a management device according to claim 9, comprising after the step of opening the islanding switch (7) a step of supplying the non-critical loads of the local network by the domestic battery (11), via the network forming inverter (14).