Island operation module for a distribution box for a network to set up island operation in the event of a failure of a public network, as well as distribution box

Abstract

The invention relates to an islanding module (64) for a distribution box (10) for a network (16) for setting up island operation in the event of a failure of a public network (14), comprising at least one auxiliary power source (130), a monitoring device (144) for monitoring the public network (14), and a system reference conductor switching device (148) for generating a local earth (PE). The invention further relates to a distribution box (10).

Description

[0001] The following invention relates to an island operating module for a distribution box for a network for setting up island operation in the event of a failure of a public network according to claim 1. The invention further relates to a distribution box.

[0002] It is already known from the prior art that, for example, for the island operation of a network, especially a house network, a corresponding external distribution system is provided, which, for example, detects a power outage in the public grid and then enables switching to island operation via appropriate relays. For this purpose, it can be provided, for example, that these relays are connected to a battery storage system, such as a photovoltaic system, and thus provide electrical energy for island operation.

[0003] This includes, in particular, so-called hybrid inverters, which can transmit power in both grid-connected and off-grid modes. Most manufacturers offer a separate control box that handles the corresponding additional functions. Generally, there are many variants available, suitable for a wide range of applications depending on the country and grid system.

[0004] A transfer switch like this is additional hardware that must be installed, configured, and tested by an electrician in addition to the regular electrical installation, resulting in extra space requirements and costs. The transfer switch is generally only suitable for one power source and not for multiple sources, such as an additional battery inverter or bidirectional charging stations.

[0005] The object of the present invention is to create an island operating module and a distribution box by means of which improved island operation for a network, in particular a house network, can be realized.

[0006] This task is accomplished by an island operating module and a distribution box according to the independent patent claims. Advantageous embodiments are specified in the dependent claims.

[0007] One aspect of the invention relates to an islanding module for a distribution box for a network for setting up island operation in the event of a failure of a public network, comprising at least one auxiliary power source, a monitoring device for monitoring the public network, and a system reference conductor switching device for generating a local earth.

[0008] This allows for the provision of an islanding module that can be installed directly into a distribution box without the need for an external distribution box. The islanding module includes an auxiliary power source to ensure a continuous supply of electrical energy for switching operations during a public grid outage. The monitoring device is specifically designed to switch to islanding mode when the public grid fails. Furthermore, the monitoring device can be configured to detect the energy flow upon restoration of the public grid and thus deactivate islanding mode. The system reference circuit breaker is specifically designed to create a local ground connection, enabling islanding mode to be activated again.

[0009] In particular, the same emergency power supply functionality can be achieved in island mode with less hardware, space, cost, and installation time. The distribution box can be pre-assembled at the factory with the corresponding island mode module based on an online configuration. The final configuration is performed digitally, for example, using a dedicated online tool that allows for the configuration of the energy storage system and the definition of the critical circuits that must be supplied by emergency power sources. The flexibility of the island mode module always offers a simpler configuration solution, especially when using the provided pre-configured use cases for each country and grid system.

[0010] According to an advantageous embodiment, the auxiliary power source is a low-voltage battery. For example, the islanding module can incorporate the low-voltage battery to ensure a reliable power source for switching operations even during a grid outage. This allows switching operations to continue even when the public grid fails, for instance, to disconnect the system from the grid and enter islanding mode.

[0011] It is also advantageous if the auxiliary power source is designed as a DC-DC converter and is configured for connection to a grid-connected battery storage system. For this purpose, the battery storage system must have suitable terminals that can continuously supply power to the DC-DC converter. The DC-DC converter can thus be connected directly to the battery storage system, eliminating the need for additional low-voltage batteries. The DC-DC converter can then provide the necessary electrical energy to perform switching operations for island operation.

[0012] It has also proven advantageous for the monitoring device to include at least one external current sensor for monitoring current flow in the public grid. Specifically, external current sensors, such as CT terminals, are placed upstream of the switching device for islanding mode and connected to the corresponding terminals. This allows for reliable verification of whether electrical energy can be supplied by the public grid and thus enables reliable detection of a public grid failure.

[0013] It is also advantageous if the monitoring device has at least one external voltage sensor for monitoring the public grid. This allows the voltage at the public grid to be monitored accordingly. The signals can then be converted and used, in particular, to monitor energy flow. This information can, in turn, be used, for example, to control the energy storage system to provide electrical energy to the grid.

[0014] It is further advantageous if the islanding module is configured to transmit an operating signal to a control unit in the distribution box. In particular, the current operating status of the islanding mode can be transmitted as the operating signal. The control unit can then be linked to the islanding mode. For example, it can be configured that different loads are controlled depending on predefined parameters. For instance, it can be configured that only a predetermined number or a selected number of electrical loads are supplied with power in islanding mode.In other words, if the islanding module transmits an operating status as islanding to the control unit, it can be provided that only selected devices or consumers receive electrical energy, thereby enabling reliable operation of the network in island mode.

[0015] It has also proven advantageous to house at least the auxiliary power source, the monitoring device, and the system reference switchgear in a single enclosure. Specifically, this enclosure is the housing of the islanding module. This allows the corresponding modules (at least three) to be provided within a single enclosure, which can be easily installed within the distribution box. Therefore, a separate distribution box for the islanding module and its sub-modules is not required. The islanding module can be reliably installed within the distribution box.

[0016] Furthermore, it has proven advantageous if the system reference conductor switching device is designed to switch a neutral conductor of the network to the local earthing system in island mode. In particular, in island mode, a relay is thus closed to establish a connection between the neutral conductor and the local earthing system, enabling the implementation of a local TN-S system.

[0017] In a further advantageous embodiment, an additional current sensor is provided for monitoring the neutral conductor connected to earth. In particular, this additional current sensor can thus be used to monitor the current in the reference conductor and to provide redundant protection against electric shock.

[0018] It has proven advantageous for the system reference conductor switchgear to include an additional voltage sensor. In particular, the relay's condition must also be monitored to quickly detect any malfunction. The additional voltage sensor provides a reading for the voltage between one of the phases and the corresponding reference conductor. If the relay is not properly closed, this voltage will be either floating or pulled down by a high-resistance component. Detection of this malfunction then triggers an automatic shutdown of the emergency power sources.

[0019] In a further advantageous embodiment, the islanding module is provided with at least one input terminal for receiving electrical energy from a grid-connected power generator. This allows the power generator to be reliably controlled via the islanding module. The input terminal can be part of the islanding module or a separate component.

[0020] It has also proven advantageous if the energy generator is a grid-connected photovoltaic system and / or a grid-connected battery storage system. In particular, the grid can, for example, include both a photovoltaic system and a battery storage system. The off-grid module can then take over the control of the photovoltaic system and the battery storage system. This ensures reliable operation, especially during off-grid operation.

[0021] Furthermore, it has proven advantageous for the islanding module to have at least one output terminal for communicating with an external communication device. This external communication device can, for example, be a router. This allows information regarding the current operating status, particularly the islanding mode, to be transmitted to an external device, such as a user device. Thus, the user can be informed about the current operating status of the islanding module and, consequently, the distribution box. The output terminal can be part of the islanding module or a separate component.

[0022] In a further advantageous embodiment, the islanding module is provided with at least one output terminal for supplying electrical energy to an electrical load. For example, this allows for the provision of emergency power to the electrical load. In particular, an islanding module can also have multiple output terminals to supply several electrical loads accordingly. This enables reliable island operation. The output terminal can be part of the islanding module or a separate component.

[0023] Another aspect of the invention relates to a distribution box for a network with at least one islanding module according to the preceding aspect. The distribution box is specifically designed as a so-called intelligent distribution box and includes a multitude of additional modules to enable intelligent operation. In particular, the distribution box also utilizes solid-state technology and, for example, additionally includes a solid-state switch to allow for the necessary isolation of the network from the public grid within the distribution box.

[0024] Furthermore, the distribution box has at least the control device to enable appropriate control measures to be carried out within the distribution box.

[0025] Advantageous designs of the island operating module are to be regarded as advantageous designs of the distribution box.

[0026] A computing unit / control unit can be understood, in particular, as a data processing device containing a processing circuit. The computing unit can therefore process data to perform arithmetic operations. This may also include operations to perform indexed access to a data structure, such as a lookup table (LUT).

[0027] The computing unit may, in particular, contain one or more computers, one or more microcontrollers, and / or one or more integrated circuits, for example, one or more application-specific integrated circuits (ASICs), one or more field-programmable gate arrays (FPGAs), and / or one or more systems on a chip (SoCs). The computing unit may also contain one or more processors, for example, one or more microprocessors, one or more central processing units (CPUs), one or more graphics processing units (GPUs), and / or one or more signal processors, in particular one or more digital signal processors (DSPs). The computing unit may also include a physical or virtual array of computers or other units of the aforementioned type.

[0028] In various embodiments, the computing unit includes one or more hardware and / or software interfaces and / or one or more storage units.

[0029] A storage unit can be volatile data storage, for example as dynamic random access memory (DRAM) or static random access memory (SRAM), or as non-volatile data storage, for example as read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory or flash EEPROM, ferroelectric random access memory (FRAM), or magnetoresistive random access memory.It can be designed as MRAM (magnetoresistive random access memory) or as phase-change random access memory, PCRAM (phase-change random access memory).

[0030] Regardless of the grammatical gender of a particular term, persons with male, female or other gender identities are included.

[0031] Further features and combinations of features of the invention will become apparent from the figures and their descriptions, as well as from the claims. In particular, further embodiments of the invention need not necessarily include all features of any one of the claims. Further embodiments of the invention may have features or combinations of features that are not mentioned in the claims.

[0032] This shows: Fig. 1 a schematic block diagram of an embodiment of a distribution box; and Fig. 2 another schematic block diagram of an embodiment of a distribution box.

[0033] In the figures, identical or functionally equivalent elements are provided with the same reference symbols.

[0034] Fig. Figure 1 shows a schematic block diagram according to an embodiment of a distribution box 10 with a corresponding housing 12 of the distribution box 10. In particular, it is shown that the distribution box 10 is connected to a public network 14. Furthermore, the distribution box 10 is designed for distributing electrical energy for a network 16. For this purpose, several consumers 18, 20, 22, 24 are shown. For example, a first consumer 18 can be represented as a light or refrigerator. A second consumer 20 can be represented, in particular, as a heat pump. Furthermore, a third consumer 22 is shown as sockets. A fourth consumer 24 is provided as a charger for a motor vehicle that is at least partially electrically powered.

[0035] Furthermore, a sub-distribution board 26 is shown, which can also be supplied with electrical energy via the distribution box 10, for example. The figure also shows... Fig. 1 a photovoltaic system 28 and a battery storage system 30.

[0036] The Fig. Figure 1 further shows that an input terminal 32 can be provided, which can be connected to the public network 14 via a corresponding input fuse 34. The main fuse 34 is, in particular, mounted on an additional mounting rail 36. A solid-state switch 38 is, in particular, provided above the input terminal 32. A cooling device 40 and a surge protector 42 are also shown. Furthermore, the distribution box 10 includes an input / output module 44 and a residual current module 46. A meter 48 and a DC-DC converter 50 are also shown. The distribution box 10 also includes a communication module 52 and a control device 54. Finally, a two-pole module with an RCD 56 is shown, which is, in this case, connected to the first load 18.Furthermore, several single-pole modules 58 are shown, which are connected to the individual phases of the distribution box 10 and can, for example, also be connected to electrical loads 18, 20, 22, 24. An additional residual current protection module 60 is also provided for this purpose. Furthermore, two three-pole modules with RCDs 62 are shown, which can, for example, be connected to the fourth load 24, the photovoltaic system 28, and the battery storage system 30. The [reference to be added] further shows... Fig. 1 an island operating module 64 and a local grounding 66. Furthermore, a power distributor 68 is shown, which communicates with the island operating module 64 in particular, for example via the communication module 52.

[0037] The Fig. Figure 2 shows a schematic block diagram according to an embodiment of the distribution box 10, for example from Fig. 1. It is shown in particular that the individual modules can be interconnected via a power distribution bus 70. The input terminal 32 can, in particular, be four-pole and, for example, have a first phase L1, a second phase L2, and a third phase L3. Furthermore, a neutral conductor N and an earth PE are shown. The solid-state switch 38, for example, has a solid-state module 72. The cooling device 40, for example, has a fan 74. The input-output module 46, for example, has an input terminal 76, an output terminal 78, a switch insulator 80, and a logic device 82. The counter 48 has a voltage sensor 84 and a current sensor 86, which can be combined in a corresponding measuring device 88. The DC voltage module 50, in particular, has a DC-DC converter 90, in particular an AC / DC converter.The communication module 52 can, for example, include a LAN terminal 92 and a WLAN terminal 94. The control unit 54 again includes at least one logic unit 96.

[0038] The two-pole module with FI 56 comprises switching elements 98, a logic device 100, a residual current circuit breaker 102, a current sensor 104, and a voltage sensor 106. A corresponding output terminal 108 is also shown.

[0039] The single-pole module 58 includes, in particular, a switching element 110, a logic device 112, a current sensor 114, and a voltage sensor 116. An output terminal 118 is also shown.

[0040] The four-pole module with FI 62 has switching elements 120, a logic device 122, a current sensor 124 and a voltage sensor 126. Corresponding output terminals 128 are also shown.

[0041] The islanding module 64 comprises an auxiliary voltage source 130, a first output terminal 132 for the auxiliary voltage source 130, a three-pole output terminal with neutral conductor 134, and CT outputs 136. A voltage sensor 138 and a current sensor 140 are also shown. Furthermore, a counter 142 is shown. The islanding module also includes a logic device, in particular a monitoring device 144, as well as another voltage measuring device or another voltage sensor 146. A system reference conductor switching device 148 and a fault protection element 150 are also shown.

[0042] The local earthing 66 in turn has an earthing terminal 152.

[0043] In particular, it is thus provided that the islanding module 64 for the distribution box 10 is designed for the network 16 and is specifically designed for islanding operation in the event of a failure of the public network 14. For this purpose, the islanding module 64 has at least the auxiliary power source 130, the monitoring device 144 for monitoring the public network 14 and the system reference conductor switching device 148 for generating a local earth connection 66.

[0044] The auxiliary energy source 130 is, for example, designed as a low-voltage battery. As shown here, the auxiliary energy source 130 is specifically designed as a DC / DC converter and is configured for connection with, for example, a battery storage device 30.

[0045] The monitoring device 144 may include at least one external current sensor 140 for monitoring a current flow in the public network 14. The monitoring device 144 may also include at least one external voltage sensor 146 for monitoring the public network 14.

[0046] The island operating module 64 is specifically designed to transmit an operating signal to the control device 54 of the distribution box 10.

[0047] Furthermore, at least the auxiliary power source 130, the monitoring device 144 and the system reference conductor switchgear 148 can be arranged in a common housing.

[0048] The system reference conductor switching device 148 is specifically designed to switch the neutral conductor N of the network 16 to the local earthing 66 in island operation, which is coupled in particular to the earthing PE.

[0049] Furthermore, an additional current sensor can be provided to monitor the neutral conductor N connected to ground. The system reference switching device 148 includes, in particular, an additional voltage sensor 138. Furthermore, the islanding module 64 can have at least one input terminal for receiving electrical energy from a power generator of the network 16. The power generator can also be the photovoltaic system 28 of the network 16 and / or the battery storage system 30 of the network 16.

[0050] The island operating module 64 still has at least one output terminal for communicating with the external communication device 154.

[0051] In particular, the input terminals and the output terminals are shown separately from the housing of the island operating module and are equipped with the switching element 68.

[0052] The in Fig. 1 and Fig.The distribution box 10 shown in Figure 2 already fulfills the functions of the switch, which is mounted, for example, on a DIN rail and controlled by a remote control. It can be configured for three- or four-phase operation. The neutral conductor N can be disconnected if necessary. The remote control has auxiliary outputs that indicate the actual state of the switch, thus enabling monitoring of the switch position. In the event of a fault, the distribution box 10 can switch off the semiconductor switches and / or disconnect the power sources, thereby providing redundancy. The outputs of the input / output module 44 are used to control the remote control and the position of this switching element. The inputs of the input / output module 44 are used to monitor the position of the switching element 68.

[0053] Depending on the available energy from emergency power sources, the loads in the system can be switched off if they can be controlled via a common bus, for example, heat pumps or charging stations, or by the output relays or by switching off one or more of the semiconductor switches, thereby switching off one or more phases L1, L2, L3 of the sub-distribution box 26, which is connected between the switching element 68 and the input terminals of the smart distribution box 10. If the sub-distribution box 26 is also configured as a smart distribution box, for example, it can communicate and be configured to keep certain relays open or closed in emergency power mode.

[0054] Two residual current protection modules 46, 60 are arranged at key positions. The first monitors the differential current between the input terminals, in particular the downstream public network 14 and the sub-distribution box 26, and the input-output relays. The second monitors the differential current between the relays for the loads and the relays for potential current sources. In the event of a fault, the relays can be opened for protection.

[0055] The smartboard, i.e., the distribution box 10, can monitor the power quality with its own smart meters and switch off via the switching element 68 or via semiconductor switches if the corresponding requirements are no longer met.

[0056] Furthermore, disconnection from the public grid 14 can be easily accomplished using the relay or by sending commands to the relevant power sources via the bus system. The decision to disconnect can be communicated by the energy supplier via the communication module 52 or programmed for automatic disconnection based on the measured grid quality.

[0057] The remaining functions are specific to island operation and require additional hardware, which is implemented in the form of the island operation module 64.

[0058] An auxiliary terminal can be connected to any power source of the electrical energy storage unit 30, for example, to a permanent DC output of a battery or a separate AC output of an inverter. The internal converter is configured with a sufficiently large output, for example, 12 volts to 250 volts AC or DC, to be compatible with most devices. This function can also be implemented with an optional battery module; however, handling, transporting, and replacing the battery are not straightforward.

[0059] External current sensors are placed upstream of the switching element 68 and connected to the corresponding terminals. Wires are also connected to monitor the voltage. The signals are converted and processed to monitor the power at this point. This information is provided to the battery storage unit 30 and used to control the power source to optimize self-consumption when the distribution box 10 is connected to the public grid 14. In island mode, monitoring the voltage at this point allows the system to determine whether the public grid 14 has been restored after a power outage and whether island mode can be terminated.

[0060] In island operation, a relay is closed to establish a connection between the neutral conductor (N) and the protective earth (PE) as a local earth connection (66), thus creating a local TN-S system. An additional current sensor can be used to monitor the current in this reference conductor and provide redundant protection against electric shock. The relay's status must also be monitored to quickly detect any malfunction. A voltage sensor provides a reading for the voltage between one of the phases (L1, L2, L3) and the reference conductor. If the relay is not properly closed, this voltage will be suspended or pulled down by a high-resistance resistor. Detecting a malfunction leads to the automatic shutdown of the emergency power sources. List of reference symbols 10 distribution boxes 12 cases 14 public network 16 network 18 first consumer 20 second consumers 22 third consumer 24 fourth consumer 26 sub-distribution boxes 28 Photovoltaic system 30 battery storage units 32 Entrance terminal 34 Input fuse 36 Mounting rail 38 solid-state switches 40 Cooling equipment 42 Surge protection 46 Input / Output Module 48 Residual current protection module 50 counters 52 Communication module 54 Control device 56 two-pole module with RCD 58 single-pole module 60 additional residual current protection modules 62 four-pole module with RCD 64 Island operating module 66 local grounding 68 switching element 70 power distribution buses 72 Solid-state modulus 74 fans 76 entry terminals 78 Exit terminal 80 Switch insulation 82 Logic device 84 Voltage sensor 86 Current sensor 88 Measuring device 90 AC / DC converter 92 LAN terminal 94 WLAN terminals 96 Logic device 98 switching element 100 logic device 102 Residual current circuit breakers 104 Current sensor 106 Voltage sensor 108 Exit terminal 110 Switching device 112 Logic device 114 Current sensor 116 Voltage sensor 118 Exit terminal 120 switching device 122 Logic device 124 Current sensor 126 Voltage sensor 128 Exit terminal 130 Auxiliary power source 132 Exit terminal 134 Exit germinal 136 CT outputs 138 Voltage sensor 140 current sensor 142 Measuring device 144 Monitoring device 146 Voltage sensor 148 System reference circuit breaker 150 residual current protection 152 PE terminal L1 first phase L2 second phase L3 third phase N Neutral conductor PE grounding

Claims

[1] Island operation module (64) for a distribution box (10) for a network (16) for setting up island operation in the event of a failure of a public network (14), comprising at least one auxiliary power source (130), a monitoring device (144) for monitoring the public network (14), and a system reference conductor switching device (148) for generating a local earth (PE). [2] Island operating module (64) according to claim 1, characterized by , that the auxiliary power source (130) is a low-voltage battery. [3] Island operating module (64) according to claim 1 or 2, characterized by , that the auxiliary power source (130) is designed as a DC voltage converter and is designed to connect to a battery storage (30) of the network (12). [4] Island operating module (64) according to any one of the preceding claims, characterized bythat the monitoring device (148) has at least one external current sensor (140) for monitoring a current flow in the public network (14). [5] Island operating module (64) according to any one of the preceding claims, characterized by that the monitoring device (144) has at least one external voltage sensor (146) for monitoring the public network (14). [6] Island operating module (64) according to any one of the preceding claims, characterized by , that the island operating module (64) is designed to transmit an operating signal to a control device (54) of the distribution box (10). [7] Island operating module (64) according to any one of the preceding claims, characterized by , that at least the auxiliary power source (130) and the monitoring device (144) and the system reference conductor switchgear (148) are arranged in a common housing. [8] Island operating module (64) according to any one of the preceding claims, characterized by, that the system reference conductor switching device (148) is designed to switch a neutral conductor (N) of the network (16) to the local earthing (PE) in island operation. [9] Island operating module (64) according to claim 8, characterized by , that an additional current sensor is provided to monitor the neutral conductor (N) connected to the earth (PE). [10] Island operating module (64) according to any one of the preceding claims, characterized by , that the system reference conductor switchgear (148) has an additional voltage sensor. [11] Island operating module (64) according to any one of the preceding claims, characterized by , that the island operating module (64) has at least one input terminal for receiving electrical energy from a power generator (28, 30) of the network (16). [12] Island operating module (64) according to any one of the preceding claims, characterized by, that the energy generator (28, 30) is a photovoltaic system (28) of the grid (16) and / or a battery storage system (30) of the grid (16). [13] Island operating module (64) according to any one of the preceding claims, characterized by , that the island operating module (64) has at least one output terminal for communicating with an external communication device (154). [14] Island operating module (64) according to any one of the preceding claims, characterized by , that the island operating module (64) has at least one output terminal for providing electrical energy to an electrical consumer (18, 20, 22, 24). [15] Distribution box (10) for a network (16) with at least one island operating module (64) according to one of claims 1 to 14.

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