Electrical power supply system

Abstract

An electrical power supply system for an establishment such as a house or shop includes a consumer unit 16 connected to a connection for an AC mains electricity supply to provide AC electrical power;

Description

This invention relates to an electrical power supply system for an establishment. The term "establishment" is used to refer to any property, domestic or commercial, that has a dedicated supply of mains AC electrical power. For example, the establishment could be a house or flat, a shop, or a commercial unit within a multi-establishment development such as a shopping mall or the like. The electrical power supply to an establishment will typically comprise a connection to an AC mains electrical power supply ("mains supply"). The main supply is connected to a consumer unit that will typically comprise of a main connection, often including a consumption meter, and a distribution board or fuse or breaker panel. The electrical supply within the establishment will typically comprise of one or more circuits such as ring main circuits or radial circuits. Mains supply is usually three-phase AC. The consumer unit will usually provide a single-phase AC supply to each circuit. Battery and inverter systems are known for use with such establishments as a way to provide an alternative to the mains supply. Such systems have been used to store electrical energy from solar panels for use at night, or for storing electrical energy against failure of the mains supply. Such systems are typically installed before the distribution board, i.e. on the "supply" side of the system. In this configuration, the battery and inverter / charger simply take the place of the mains supply for the whole establishment. Because a typical establishment will have a number of different loads on the electrical system, the battery and inverter / charger system on the supply side must be capable of dealing with all of these but spend most of their time operating well below maximum load. This invention provides a backup system that can be used to operate constant but lower level demands and so is useful for activities 23 05 23 such as overnight lighting, or maintaining constant loads such as refrigeration units. The invention provides an electrical power supply system for an establishment as defined in the claims. By connecting the battery and inverter / charger system after the consumer unit (i.e. on the "load" side) to a single circuit, such as a single ring main or single radial circuit of the AC electrical power supply within the establishment and providing a switch between the consumer unit(single circuit) and the connection of the battery inverter / charger system, a power supply backup can be provided that does not need to be capable of meeting the load of all circuits and so can be cheaper and enable a focus on electrical appliances which draw the most current over time. A communication link between the control unit and a communication unit in the switch that controls operation of the switch is configured so that it will only control the battery inverter / charger system to draw electrical power from or provide electrical power to the AC electrical power supply when a valid communication link between the control unit and the switch unit is established. This avoids activation of the backup without full control of the system. The control unit can be configured to automatically open the switch to isolate the battery and inverter / charger system from the AC mains electrical power supply to the establishment if it detects that the AC mains electricity supply to the establishment has failed. This avoids the battery accidentally discharging into the mains system. The control unit can be configured to control the battery inverter / charger system to provide electrical power to the selected / installed AC electrical power supply circuit within the establishment until the AC mains electrical power supply is restored or the battery is discharged in the manner of an uninterruptable power supply. The control unit can be configured to automatically isolate the battery and inverter / charger system from the AC electrical power supply within the establishment if it detects a fault in the system. This helps avoid accidental discharge or overcharging due to the fault. The communication link can use an independent wireless communication link if needed so that it is not affected by interruption of the power supply within the establishment causing routers and Wi-Fi systems to fail. 23 05 23 A remote device, such as a mobile phone or tablet can be used to control the system remotely, for example by using an app connected via the Internet and using a wireless link to connect to the control unit. A provider of the AC mains electricity supply to the establishment can also connect to the control unit to start and stop charging of the battery. Figure 1 shows a schematic view of a system according to the invention in a first configuration. Figure 2 shows a schematic view of a system according to the invention in a second configuration. The system shown in Figure 1 could be a single ring main within a commercial establishment used to power low level devices such as lights. The system comprises a mains AC supply 10 which feeds a consumption meter 14 and a distribution board 16 defining a consumer unit. The distribution board 16 will typically provide outputs to a number of individual circuits such as ring mains or radial circuits. Each individual circuit will provide single-phase electrical power on live, neutral, and earth cabling 18, up to a level limited by a fuse or breaker in the distribution board 16. A smart switch device 20 is installed in the cabling 18 after the distribution board 16. The switch 20 has linked switches 20a, 20b in the live and neutral wires. In Figure 1, the linked switches 20a, 20b are shown closed so that the supply from the board 18 can pass onto the circuit. The switch device 20 also has a wireless communication unit 22 that also includes an Internet connection 24. The wireless communication unit controls operation of the linked switches 20a, 20b. The output of the switch device 20 connects to a 23 05 23 ring main circuit 26 that supports a number of switched outlets 28 to which devices such as lights can be connected. A battery and inverter / charger control unit 30 is connected to the circuit 26 after the switch 20. The control unit 30 can comprise, for example, a 5kWh LiFePo4 48v battery with a 3KW inverter / charger. The rating of the battery and inverter / charger can be selected according to the individual supplied circuit requirements. The unit also comprises a control unit including a wireless communication unit 32 and an Internet connection 34. In Figure 1, the control unit 30 operates to control the unit to charge the battery from the AC supply on the circuit 26. The control unit also provides control of the switch 20 via the wireless communication units 32, 22. For example, the communication units 32, 22 can include a WiFi and Ethernet card, and other systems such as Zigbee, NFC, and / or Bluetooth. The control unit 30 will check that there is a valid communication link between the switch 20 and unit 30, that the mains AC supply 10 is operating, and that there are not other faults detected in the system. Provided that these conditions are met, the linked switches 20a, 20b can be closed and power provided to the circuit 26 and the battery can charge. A remote device 36, such as a mobile phone, tablet, or PC with an Internet connection 38, can be used for overall control of the system and can instruct the unit 30 to issue control signals to operate the switch 20 depending on criteria such as time of day, cost of electricity, establishment status (e.g. shop closed), etc. The provider 40 of the mains AC supply 10 can also have a control unit 42 with an Internet connection 44 so that can also control operation of the system according to pre-set criteria. In the configuration of Figure 1, the circuit 26 will operate as normally and the battery will charge until at capacity. Figure 2 shows the system in an alternative configuration. This can occur, for example, when the establishment only needs a low level of electrical supply, such as when a shop is closed, to run constant level devices such as lighting, alarm systems, coolers, etc. When the appropriate condition is reached, such as a specific time of day, or on receipt of a signal from a remote unit 36, the communication unit 32 will send a signal to the switch 20 to open the linked switches 20a, 20b so as to disconnect the circuit 26 from the mains supply. At the same time, the unit 30 is configured to discharge though the inverter / charger into the circuit 26 to provide Ac electrical power. The same configuration can be adopted if failure of the mains supply 10 is detected. 23 05 23 The system can then continue to operate in this fashion until a predetermined condition is reached, such as a time or external control input, or until the battery is fully discharged. At this point, the switches 20a, 20b can be closed again to reconnect the circuit 26 to the mains supply and recharge the battery according to the preset parameters . Various changes can be made within the scope of the invention. 23 05 23

Claims

1. An electrical power supply system for an establishment, comprising:a connection to an AC mains electricity supply;a consumer unit connected to the connection for the AC mains electricity supply and configured to provide an AC electrical power supply within the establishment;one or more circuits within the establishment, each supporting a number of switched outlets; anda battery and inverter / charger system connected to the AC electrical power supply and operable to provide AC electrical power on each circuit in the AC electrical power supply within the establishment;whereinthe battery and inverter / charger system is connected after the consumer unit to a single circuit of the AC electrical power supply within the establishment and is configurable to either draw electrical power from the AC electrical power supply within the establishment to charge the battery from the AC mains electricity supply or provide electrical power to the AC electrical power supply within the establishment; andthe electrical power supply system further comprises:a switch, positioned in AC electrical power supply within the establishment between the consumer unit and the connection of the battery inverter / charger system, and configurable between a closed position in which the single circuit is connected to the consumer unit and an open position in which the single circuit is disconnected from the consumer unit;a control unit operable to operate the switch to open or close, and to control the battery inverter / charger system to draw electrical power from or provide electrical power to the AC electrical power supply; anda communication link between the control unit and a communication unit in the switch that controls operation of the switch, wherein the control unit is configured so that it will only control the battery inverter / charger system to draw electrical power from or provide electrical power to the AC electrical power supply when a valid communication link between the control unit and the communication unit in the switch is established.

2. A system as claimed in claim 1, wherein the AC electrical power supply within the establishment has more than one circuit, and the switch and battery and inverter / charger system are provided in a single ring main or radial circuit of the AC electrical power supply within the establishment.23 05 233. A system as claimed in claim 1 or 2, wherein the control unit is configured to automatically open the switch to isolate the battery and inverter / charger system from the AC mains electrical power supply to the establishment if it detects that the AC mains electricity supply to the establishment has failed.

4. A system as claimed in claim 3, wherein the control unit is configured to control the battery inverter / charger system to provide electrical power to the AC electrical power supply within the establishment until the AC mains electrical power supply is restored or the battery is discharged.

5. A system as claimed in any preceding claim, wherein the control unit is configured to automatically isolate the battery and inverter / charger system from the AC electrical power supply within the establishment if it detects a fault in the system.

6. A system as claimed in any preceding claim, wherein the control unit is controllable by a user using a remote device that is connectable to the control unit by wireless communication.

7. A system as claimed in any preceding claim, wherein a provider of the AC mains electricity supply to the establishment can connect to the control unit to start and stop charging of the battery.23 05 23

Images