Local area network power management device

Abstract

The invention relates to a power management device (1) integrating a network input (3); a local area network power interface (5); an islanding switch (7); an uninterruptible power supply (9); a central controller (10); at least one domestic or industrial battery (11); at least one bidirectional electric vehicle charging station (12) (13) connected to the domestic or industrial battery (11) so that the domestic or industrial battery (11) can be used to charge the electric vehicle (13) and, when an electric vehicle (13) is plugged in with sufficient charge, a battery of the electric vehicle can be used to charge the domestic or industrial battery (11);a grid forming inverter (14) so ​​that the power management device can operate in an islanding mode in which the home or industrial battery (11) and / or the electric vehicle battery (13) supply the power interface (5). Figure for the abstract: Fig 1;

Description

Title of the invention: Local area network power management device. Technical field

[0001] The present invention relates to the management of the power supply of a local electrical network, in particular for a dwelling or an industrial installation.

[0002] The invention finds a particularly advantageous application for optimizing the use of a domestic or industrial battery and an electric vehicle battery, both when the local network is supplied by the distribution network (mode “off-grid”), and when the local network is supplied by one or both of the aforementioned batteries (mode “on-grid”). Previous technique

[0003] With rising energy costs and growing concerns about the environmental impact of traditional energy sources, it is becoming imperative to develop efficient and sustainable solutions for managing the power supply of local consumer electricity networks.

[0004] These solutions are advantageously compatible with domestic energy production methods, such as photovoltaic panels, and allow for the best use of available storage capacities such as domestic or industrial batteries, and batteries of electric vehicles connected to the local network via a charging station.

[0005] These solutions sometimes include an "off-grid" or islanding mode, allowing the local network to be supplied without using the external distribution network.

[0006] US patent 11011913 proposes such a system, enabling an islanding mode in which the local grid is powered by an electric vehicle battery and / or a home battery. This system has the disadvantage of being complex, requiring a large number of components, and causing a temporary interruption of the local grid power supply when the control system is triggered.

[0007] The technical problem of the invention is therefore to propose a power management system for a local network which allows the energy stored in a domestic or industrial battery and in an electric vehicle to be used in an optimized and economically efficient manner, in "on-grid" and "off-grid" mode, the system being arranged in an original way in order to reduce the number of components required and to allow the uninterrupted supply of the local network. Description of the invention

[0008] The present invention aims to address this technical problem by proposing a power management device for a local area network integrating: - a network input, configured to be connected to a public electricity network; - a local network power interface; - an islanding switch, one terminal of which is connected to the network input; - a voltage sensor, disposed between the network input and the islanding switch; - an uninterruptible power supply disposed between a second terminal of said islanding switch and the power interface of a local network, said uninterruptible power supply being configured to maintain the local network power supply without interruption for a first predetermined period; - a central controller, configured to receive measurements from said voltage sensor and open the islanding switch when the measured voltage is below a certain threshold for a second predetermined duration; - at least one domestic or industrial battery capable of supplying the local network for a third predetermined period, longer than the first predetermined period; - at least one bidirectional electric vehicle charging station connected to the domestic or industrial battery so that the domestic or industrial battery can be used to charge the electric vehicle and, when an electric vehicle is plugged in with sufficient charge, that a battery of the electric vehicle can be used to charge the domestic or industrial battery; - a grid forming inverter, comprising an AC input connected to the second terminal of said islanding switch, and a DC output connected to the domestic or industrial battery and to the bidirectional charging station, so that the power management device can operate in an islanding mode in which the domestic or industrial battery and / or the electric vehicle battery supply the power interface.

[0009] The invention thus makes it possible to optimize the use of batteries since, in normal operating mode, the domestic or industrial battery can be used in addition to the power supplied on the network input to power the charging station and allow a fast charging of the electric vehicle.

[0010] Furthermore, in islanding mode, the home or industrial battery can be supplemented by the electric vehicle battery to ensure the longest possible supply to the local grid. In this islanding mode, the electric vehicle can be disconnected, and only the home or industrial battery supplies the local grid. Moreover, by regularly recharging the electric vehicle at fast charging stations, it is even possible to recharge the home or industrial battery and supply the local grid with the electric vehicle battery. to guarantee a local network supply theoretically for an unlimited period, provided that the battery capacity of the electric vehicle is sufficient with regard to the consumption of the local network.

[0011] Between normal operating mode and islanding mode, the uninterruptible power supply provides power to the local network. This uninterruptible power supply is preferably also used to power certain components of the power management device of the invention, in particular the central controller, the auxiliary components of the domestic or industrial battery and the inverter, and the islanding switch.

[0012] The quality of the electrical signal on an islanded network, particularly its harmonic distortion, is generally lower than on a non-islanded network and, depending on the sensitivity of the electrical components on the islanded network, may require the use of costly filtering systems. An uninterruptible power supply (UPS), as positioned downstream of the grid forming inverter, can filter the electrical signal entering the local network and guarantee its quality even in the event of islanding.

[0013] In addition to normal mode and islanding mode, it is also possible, in a preferred embodiment of the invention, to use the batteries to implement a balancing mode. In this embodiment, the way in which the central controller controls the management device depends on how the home or industrial battery and / or the electric vehicle battery are used. More specifically, in this mode, the central controller is configured to be able to control the power management device of a local network in a balancing mode in which the islanding switch is closed and the home or industrial battery and / or the electric vehicle battery are used to inject or withdraw power from the network input.In the first operating mode, corresponding to the first type of balancing, the central controller is connected to a device that measures the characteristics of the electrical signal from the network, specifically its voltage and frequency. In the second operating mode, corresponding to the second type of balancing, the central controller communicates with the network operator via a communication network. It then controls the balancing mode based on instructions sent by the network operator.

[0014] Another operating mode uses domestic or industrial batteries and / or electric vehicle batteries to optimize the local grid power supply when the islanding switch is closed. In this embodiment, the central controller is typically connected to a communication network and / or the installation's meter in order to control the local grid power management device to charge and discharge the batteries at the appropriate time. For example, the network power management device can be controlled to: - to charge the batteries when electricity drawn from the grid is cheap, without exceeding the maximum permitted subscribed power on the local grid; and - to use the batteries to power the local grid when electricity drawn from the grid is expensive.

[0015] In the case of an industrial or domestic installation, the needs of the local network may at times exceed the power that can be supplied by the network, causing power outages or limitations. This can occur, in particular, if the electrical power subscribed to by the consumer and measured at the installation's meter is temporarily lower than the power drawn, or more generally if the characteristics of the local network connection do not allow the local network to draw all the power it needs, at a temporary stage.

[0016] To address this type of situation, the central controller can be configured to receive a measurement of the electrical signal power measured at the grid input, and to control the management device in an overload absorption mode in which, when the power delivered by the grid is less than the local grid's needs, the home or industrial battery and / or the electric vehicle battery are used to supply the local grid in addition to the public grid. When the central controller detects an overload situation, i.e., a situation where the local grid consumption is too high compared to a fixed or measured threshold, said controller drives the grid shaping inverter so that it injects into the local grid the power necessary to absorb this overload.The corresponding energy is drawn from the domestic or industrial battery and / or the electric vehicle battery.

[0017] Thanks to these provisions, the device according to the invention allows optimal use of electrical energy resources from the network, stored in the domestic or industrial battery and in the battery of the electric vehicle, in "on-grid" mode as well as in "off-grid" mode.

[0018] The network connected to the network input may be a low-voltage network, but the network input may incorporate protection and transformation devices to connect a high-voltage or medium-voltage network, depending on the local network to be protected. In the case of a low-voltage network, the local network is preferably a domestic network. In the case of a high-voltage network, the local network is preferably an industrial network.

[0019] At least one of the loads enabling the restoration of the local network in the event of a power outage, including the central controller, the backup circuit of the network formation inverter, and the auxiliaries of the domestic or industrial battery and / or the terminal The charging unit can be connected downstream of the uninterruptible power supply, so as not to require an uninterruptible power supply for each component.

[0020] The central controller can be configured to close a grounding switch to ground the main power supply of said local network when the islanding switch is open, thereby automatically grounding the network and ensuring its safety. In a particular embodiment of the invention, this grounding switch can be directly integrated into the device.

[0021] The first predetermined duration may be less than 30 min, which is a sufficient duration to start the "off-grid" mode, and more specifically the supply of the local network via the domestic or industrial battery and / or the electric vehicle battery.

[0022] The third predetermined duration can be between 24 and 48 hours, which is generally sufficient to restore the public network following a disruption of this network.

[0023] The power of the domestic or industrial battery can be between 10 and 20 kW, which is a power output particularly suited to a typical domestic network. When the local network is an industrial network, the power of the domestic or industrial battery can be higher, for example between 20 and 500 kW.

[0024] Said management device may include an interface to a photovoltaic installation, said interface being connected to the grid forming inverter, which makes it possible to optimally use the energy produced by the photovoltaic installation in combination with the energy stored in the domestic or industrial battery, in the electric vehicle battery, and with the energy from the public grid.

[0025] Said management device may include a DC-DC converter, connected between the grid forming inverter and said bidirectional charging station, which allows the electric vehicle to be charged more quickly. Brief description of the drawings

[0026] The present invention and its advantages will become more apparent from the following description of several embodiments given by way of non-limiting examples, with reference to the accompanying drawings, in which:

[0027] Fig. 1 is a schematic view of a management device according to a preferred embodiment of the invention. Description of the implementation methods

[0028] With reference to [Fig. 1], the power management device of a local network 1 according to the invention is connected to a public network 2 via an input 3, preferably located downstream of the connection of an electricity meter 4. The network Public network 2 can be a low-voltage network, supplying, for example, to device 1 a single-phase or three-phase alternating voltage of 230 or 400 V, at a power of, for example, approximately 12 kVA. Public network 2 can also be a medium- or high-voltage network.

[0029] The device 1 includes a local network power supply interface 5, which is configured to be connected to the local network electrical panel 6. The interface 5 is preferably configured to be the sole source of power supply to the electrical panel 6. The electrical panel 6 is preferably a "TGBT" type panel, for "General Low Voltage Panel". In another embodiment of the invention, it may also be a low-voltage sub-panel, positioned downstream of a "TGBT".

[0030] The device 1 further includes an islanding switch 7, preferably mechanical, of which a first terminal 7a is connected to the input 3, and a voltage sensor 8, disposed between the islanding switch 7 and the input 3.

[0031] Device 1 further includes an uninterruptible power supply (UPS) 9, located between a second terminal 7b of the islanding switch 7 and the local area network (LAN) power interface 5. The UPS 9 has an upstream side, at the second terminal 7b, and a downstream side, at the interface 5, and ensures continuity of service to its downstream side in the event of a power outage from its upstream side. This function is, of course, time-limited and depends on the capacity of the UPS 9 and the LAN power consumption. Thus, if the LAN power supply fails, the UPS maintains the LAN power supply without interruption for a predetermined period.The first determined duration is preferably less than 30 minutes, for example on the order of a few minutes, for example 5 min. .

[0032] Device 1 further includes a central controller 10. The central controller 10 is configured to receive measurements from the voltage sensor 8, via known wired or wireless communication means, and to control the opening and closing of the islanding switch 7. When a failure of the public network 2 is detected, for example via a voltage value below a certain threshold for a second predetermined duration, the central controller 10 commands the opening of the islanding switch 7, in order to switch Device 1 to "off-grid" mode.

[0033] In order to analyze more precisely the state of the current coming from the public network 2, the voltage sensor 8 can be supplemented by a current sensor and / or a frequency sensor, which allows the central controller 10 to control the device 1 in a The network balancing operating mode, in "on-grid" mode, allows for more informed decisions regarding whether or not to switch the device to "off-grid" mode. Public network 2 supervision can be performed as described in French patent FR 3128167.

[0034] In "off-grid" mode, the local network is supplied by local energy storage means, and possibly by local energy production means.

[0035] To do this, the device 1 includes at least one domestic or industrial battery 11, and at least one bidirectional charging station 12 for an electric vehicle 13.

[0036] The domestic or industrial battery 11 is sized so as to be able to supply the local network for a third predetermined period, longer than the first predetermined period. The third predetermined period is, for example, between 24 and 48 hours.

[0037] The domestic or industrial battery 11 has, for example, a power output of between 10 and 20 kW, and a capacity of between 40 and 50 kWh.

[0038] The controller of the domestic or industrial battery 11 is preferably connected to the uninterruptible power supply (UPS) 9, on the downstream side of the UPS 9, i.e., on the side of its connection to the local network interface 5. Thus, the UPS can be configured to maintain power to the battery controller for a predetermined period. This ensures that in the event of a network failure, the power supply to the controller of the domestic or industrial battery 11 is not interrupted, and that the domestic or industrial battery 11 can therefore be used, via its controller, to contribute to the local network supply when the device 1 switches to "off-grid" mode.

[0039] In addition to the domestic or industrial battery controller 11, other domestic or industrial battery auxiliaries 11, such as ventilation, cooling or other systems, can be connected in the same way to the uninterruptible power supply 9, which allows the domestic or industrial battery 11 to be operational when the device 1 is switched to "off-grid" mode.

[0040] Similarly, the charging station controller 12 and possibly other charging station auxiliaries 12 can be connected in the same way to the uninterruptible power supply 9, which allows the electric vehicle battery 13 to be operational to supply the local network via the charging station 12 when the device 1 is switched to "off-grid" mode.

[0041] The auxiliaries of the domestic or industrial battery 11 and of the charging station 12 are represented by the reference sign “18” on the [Fig.1].

[0042] Device 1 further includes a grid formation inverter 14. The grid formation inverter 14 is a bidirectional AC / DC inverter, which includes an alternating current input, connected to the second terminal 7b of the islanding switch 7, and a direct current output connected to the domestic or industrial battery 11 and to the bidirectional charging terminal 12. The converter 14a partially behaves as a synchronous generator, delivering a voltage and frequency for the grid. The grid formation inverter 14 can therefore be used to restore a grid during a total power outage of the public grid 2, in a so-called "black start" configuration.

[0043] Thus, in the event of a partial or total interruption of the public network 2, the network formation inverter 14 is capable of restoring an electrical network, in which the domestic or industrial battery 11 and / or the electric vehicle battery 13 are used to supply the local network.

[0044] The converter 14a of the grid forming inverter 14 can also be connected downstream of the uninterruptible power supply 9, i.e., on the same side as the local grid, so that the uninterruptible power supply 9 can maintain the power supply to the converter 14a for a certain period. Thus, in the event of a partial or total outage of the public grid 2, the auxiliaries of the grid forming inverter 14, and in particular its dedicated controller, and possibly its ventilation, cooling system, etc., can be powered during a transition period by the uninterruptible power supply 9.

[0045] The charging station 12 can be connected to the grid forming inverter 14 via a DC-DC converter, allowing the current and voltage to be prepared for fast charging of the electric vehicle 13.

[0046] In a particular embodiment of the invention, the central controller 10 is configured to control an earth switch 15, preferably mechanical, located at the electrical panel 6. When the device 1 is put into "off-grid" mode, in particular by opening the islanding switch 7, the central controller 10 can command the closing of the earth switch 15, in order to ground the electrical panel 6.

[0047] The invention makes it possible to optimize the use of energy available in the domestic or industrial battery 11 and the electric vehicle battery 13. The central controller 10 can be connected, via wired or wireless communication, on the one hand to the battery controller (or battery "EMS," for "energy management system"), and on the other hand to the charging station 12, to perform this optimization. Thus, in "off-grid" mode, the central controller 10 can take into account the charge level of these batteries and their respective draw-off capacity in order to intelligently use the amount of energy they contain.

[0048] Specific configurations can be imposed on the central controller 10, and for example, it can be instructed to ensure that the battery of the electric vehicle 13 is fully charged every day at a certain time, or that it remains charged at all times, to allow for an unexpected departure at any moment. In "off-grid" mode, it may be preferable to keep the battery of the electric vehicle 13 fully or partially charged, so that the electric vehicle 13 can travel to recharge its battery outside of the device 1, in order to return energy to the device 1. This makes it possible to continue supplying the local grid in the event of a prolonged power outage, without being limited by the energy present in the domestic or industrial battery 11 and the electric vehicle battery at the time of the outage.

[0049] The central controller 10 can be in communication with a voltage and / or current sensor 19 located at the electrical panel 6, in order to take into account the instantaneous consumption of the local network in the management of the device 1.

[0050] The device 1 may include an interface 15 to a photovoltaic system 16, connected to the grid-forming inverter 14. Thus, the photovoltaic system 16 can be used to charge the home or industrial battery 11, the electric vehicle battery 13, or to supply the local grid. One or more of these services can be provided by the system simultaneously. The central controller 10, which is then in communication with the photovoltaic system 16, is configured to take into account the amount of energy produced at each instant by the photovoltaic system 16, in order to decide on the optimal way to use it.

[0051] In another embodiment of the invention, the photovoltaic installation 16 can be directly integrated into the device. It can be connected to the grid-forming inverter 14 via a DC-DC converter, allowing adjustment of the current and voltage downstream of the grid-forming inverter.

[0052] The central controller 10 can be connected to a communication network 17, in order to allow remote management and / or monitoring of the device 1. Remote management makes it possible in particular to synchronize the management of a plurality of devices 1, or to take into account in the management of device 1 the state of other elements connected to the public network 2. In addition, remote communication makes it possible to predict production by retrieving, for example, weather forecasts.

[0053] The invention allows, when the device 1 is in "on-grid" mode, to manage the consumption of the site, for example by recharging the domestic or industrial battery 11 and / or that of the electric vehicle during off-peak hours, and to discharge these batteries to absorb peak consumption during peak hours.

[0054] The device 1 according to the invention also allows for rapid charging of the electric vehicle 13, since energy can be directly drawn from the domestic or industrial battery 11, at an instantaneous power much higher than that delivered by the public network 2.

[0055] The invention makes it possible, when the device 1 is in "off-grid" mode, to maintain the continuity of power supply to certain loads, and preferably to all the loads necessary for a local network restart, using a single uninterruptible power supply 9, and therefore without resorting to a dedicated uninterruptible power supply 9 for each component. Thus, the local network can be continuously powered, with no interruption being necessary between the switch from "on-grid" mode, in which it is powered by the public network 2, to "off-grid" mode, in which it is powered by the home or industrial battery 11 and / or the battery of the electric vehicle 13, the transition step being ensured by the uninterruptible power supply 9.

[0056] The present invention is not limited to the embodiments described but extends to any modification and variant obvious to a person skilled in the art, within the limits of the appended claims. Furthermore, the technical features of the various embodiments and variants mentioned above may be combined, in whole or in part.

Claims

1. Demands Local area network power management device (1) including: - a network input (3), configured to be connected to a public electricity network; - a local network power interface (5); - an islanding switch (7) of which a first terminal (7a) is connected to the network input (3); - a voltage sensor (8), located between the network input (3) and the islanding switch (7); - an uninterruptible power supply (9) disposed between a second terminal (7b) of said islanding switch (7) and the power interface (5) of a local network, said uninterruptible power supply (9) being configured to maintain the local network power supply without interruption for a first predetermined period; - a central controller (10), configured to receive measurements from said voltage sensor (8) and open the islanding switch (7) when the measured voltage is below a certain threshold for a second predetermined duration; - at least one domestic or industrial battery (11) capable of supplying the local network for a third predetermined period, greater than the first predetermined period, and of reinjecting electricity into the network input (3); - at least one bidirectional charging station (12) for electric vehicle (13) connected to the domestic or industrial battery (11) so that the domestic or industrial battery (11) can be used to charge the electric vehicle (13) and, when an electric vehicle (13) is plugged in with sufficient charge, that a battery of the electric vehicle can be used to charge the domestic or industrial battery (11); - a grid-forming inverter (14), comprising an AC input connected to the second terminal (7b) of said islanding switch, and a DC output connected to the domestic or industrial battery (11) and the bidirectional charging terminal (12), so that the power management device can operate in an islanding mode in which The domestic or industrial battery (11) and / or the electric vehicle battery (13) power the power interface (5).

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 domestic or industrial battery (11) and / or the electric vehicle battery (13) are used to perform injection or withdrawal on the network input (3).

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 domestic or industrial battery (11) and / or the battery of the electric vehicle (13) are used to supply the local network in addition to the public network.

4. Management device (1) according to any one of claims 1 to 3, characterized in that at least one of the loads enabling the local network to be re-energized in the event of an outage, among the central controller (10), a backup circuit of the network forming inverter (14), and the auxiliaries (18) of the domestic or industrial battery (11) and / or the charging station (12), is connected downstream of the uninterruptible power supply (9), so as not to use an uninterruptible power supply for each component.

5. Management device (1) according to any one of claims 1 to 4, characterized in that the central controller (10) is configured to close an earth switch (15) enabling the general supply of said local network to be connected to earth when the islanding switch (7) is open.

6. Management device (1) according to any one of claims 1 to 5, characterized in that the first predetermined duration is less than 30 minutes.

7. Management device (1) according to any one of claims 1 to 6, characterized in that the third predetermined duration is between 24 and 48 hours.

8. Management device (1) according to any one of claims 1 to 7, characterized in that the power of the domestic or industrial battery (11) is between 10 and 20 kW.

9. Management device (1) according to any one of claims 1 to 7, characterized in that the power of the domestic or industrial battery (11) is between 20 and 500 kW.

10. Management device (1) according to any one of claims 1 to 9, characterized in that it comprises an interface (15) to a photovoltaic installation (16), said interface (15) being connected to the grid forming inverter (14).

11. Management device (1) according to any one of claims 1 to 10, characterized in that it comprises a DC-DC converter, connected between the network forming inverter (14) and said bidirectional charging station (12).

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