Shore power connection with safety devices

Abstract

A shore power connection (20) for supplying a ship, wherein the shore power connection (20) is designed and configured for the electrical connection of the on-board power grid (12) of a moored ship, in particular a container or cruise ship, and a shore-side supply grid (1), as required, in particular for multi-phase voltage supply at at least 6.6 kV or 7.2 kV and / or at at least 2 MVA connected load, wherein the shore power connection comprises a junction box with box walls enclosing an interior space, wherein the junction box comprises at least one plug-in connection unit, in particular a junction box, which is provided on a box wall for detachable plug-in connection with a corresponding plug-in connector part, in particular a plug, of a ship's supply line and is permanently connectable to a supply line of the shore-side supply grid in the interior of the junction box,and- the shore power connection comprises at least one cover part movable relative to the junction box, which, in a first position, at least partially covers the plug-in connection unit and a plug-in connector part pluggable thereto and releases them in a second position for disconnecting or connecting the plug-in connection, characterized in that at least one explosion pressure relief device is attached to the junction box and / or to the cover part, preferably to the junction box and to the cover part, and in that- the explosion pressure relief device forms a predefined relief opening with a predetermined orientation, and- the explosion pressure relief device preferably has at least one guide body, in particular a guide body arrangement, for guiding explosion gases, which arise in the event of an arc explosion, through the relief opening and into an external spatial area.,

Description

TECHNICAL FIELDThe present disclosure relates generally to the technical field of land electric power supply of ships, and more particularly to a land power connection. The term "shore power outlet" (shore power outlet) refers in the present case in particular to a connection option which is easy to connect and easy to disconnect (e.g. by means of plug connectors such as a plug or connection socket), to which a supply line or a supply cable can be connected in an easily separable manner.INTRODUCTION AND STATE OF THE ARTIt is increasingly required that ships be connected to a land power supply during harbour stay and shut down their ship generators, in particular for reducing emissions or for environmental protection. The supply of ships with electrical energy from land (Shore Power), is known under various terms (in English, for example also alternative maritime power (AMP), onshore power supply (OPS) shoreside electricity (SSE)), and is historically referred to in English as "cold ironing".The invention relates generally to the ship-land interface. This must fulfil several tasks besides the primary role of power supply. In particular, it is intended to provide a high degree of reliability and safety in order to reduce risks such as electric fire or explosion and accompanying injury to personnel, damage to material and failure of the power supply.The IEC / IEEE 80005 standard is intended to allow different ships to connect to high-voltage landing connections (HVSC) at different lying places, with as little adaptation and setting to different locations as possible.The invention is primarily intended for such supply connections in the harbour, i.e. in particular for high-voltage landing connection systems, in English: High voltage shore connection (HVSC) systems, in the sense of the IEC / IEEE 80005 standard, and is intended to be suitable in particular for an HVSC system according to IEC / IEEE 80005-1:2019. The invention thus relates in particular, but not exclusively, to a shore power connection which is designed and configured for the purpose of polyphase voltage supply at at least 6.6 kV or 7.2 kV, typically at least 2 MVA (MegaVoltAmpère) connection power.The EMSA Directive for Land-Side Power Supply for Harbour Authorities / Managers (European Maritime Safety Agency: Shore-Side Electricity-Guidance to Port Authorities and Administration, Part 2-Planning, Operations and Safety, Version 2, August 2022-cf. Chapter 9) describes various safety requirements for the land-Power Supply, including requirements for the ship-Land interface and the system used therein for line management, in English cable management system (CMS).A known and critical problem is the risk of explosion by an arcing fault (arc arc fault), hereinafter referred to for short as arc explosion. Arc explosion is a type of electrical explosion that can arise from a low impedance connection through air to a device connected to ground or other voltage phase in an electrical system. The explosion by arcing faults typically results, inter alia, in arc gases, in melting droplets, pressure waves and debris generated by the extremely hot plasma.According to IEC / IEEE 80005-1:2019, chapter 7.3.1, the electrical connections must be established in areas from which the personnel are protected in the event of an arc due to an internal fault, for example in the plug connectors, by shut-off and access control measures. These measures must be supported by access control methods.However, the intrinsic safety of the ship-land interface or of the CMS with respect to arc explosion is not improved by mere access control. As a result of human error behavior or nonconfinance of the safety regulations, the personnel can therefore continue to be exposed to the considerable risks of arc explosion.Although the probability of arc explosion is rather low, this fault case carries a very high risk potential for personnel and equipment, with potentially fatal consequences for personnel. There is therefore a need in the present field to improve the inherent safety of the ship-land interface.Known and considered as the closest prior art is the teaching from WO 20202 / 16818 A1. A shore power outlet (shore power outlet) for the required electrical connection of the on-board power network of a floating ship, for example a container ship or cruise ship, and a land-side supply network is proposed herein. Such a shore power connection typically has a connection box, which can be moved here, for example, with box walls which enclose an interior in a spray-resistant manner.A connection box of the generic type is an essential part of the ship-land interface and serves in particular to provide a plug connection unit, typically a connection box {socket outlet}, for releasable plug connection to a corresponding plug connection part, typically a plug, of a polyphase ship supply line. In the interior of the box, the plug connection unit is connected fixedly or non-detachably as intended for operation to the individual wires of a supply line of the land-side supply network, wherein further conductors, for example of a safety circuit or for data transmission, can also be provided.CN109103783A has proposed a shore power connection with a connection box which has additional measures for explosion protection, which are particularly suitable for use in environments with flammable gases, such as, for example, in the petrochemical or chemical industry. In CN109103783A, it is proposed, among other things, to provide a system for detecting combustible gases with a sensor which monitors the content of combustible gases in the environment. However, no special protective measures are specifically proposed with regard to arc explosion.To improve safety in the case of an arc explosion, it has been proposed in WO 2020 / 216818 A1 that the shore power connection comprises at least one cover part which can be moved relative to the connection box and which, in a first position, at least partially covers the plug connection unit and a plug connection part which can be plugged thereto and releases said cover part in a second position for releasing or connecting the plug connection. The proposed cover part achieves a certain protective effect against the uncontrolled propagation of the explosion and associated debris or melt on the harbourkai.The solution according to WO 2020 / 216818 A1 improves the protection against the risks of arc explosion, but potential for improvement remains. The solution according to WO 2020 / 216818 A1 in particular does not yet sufficiently reduce the effects of a possible arc ignition on the supply side on the plug connection unit or in the connection box.TECHNICAL TASKA first object of the invention is therefore to propose a generic shore power connection with an improved protective effect.According to a first independent aspect of the invention, this is achieved with the features of independent claim 1.According to a second independent aspect of the invention, this is achieved with the features of the independent claim 11.Preferred refinements emerge in each case from the dependent claims for both aspects.GENERAL DESCRIPTIONA generic shore power connection is suitable for supplying a ship, in particular a container ship or a cross-drive ship. For this purpose, the shore power connection is designed and configured in particular as a component of the ship-land interface, i.e. for the electrical connection, which can be produced as required, of the on-board power network of a constructed ship to a shore power network. The shore power connection is therefore typically designed and configured for a polyphase voltage supply at at least 6600 V and / or for a connection power of at least 2 MVA, i.e. in particular for a HVSC system according to IEC / IEEE 80005-1:2019.A generic shore power connection comprises a connection box (outlet box), with box walls which enclose an interior, in particular enclose it in a water-resistant manner, wherein the connection box has at least one plug connection unit, typically a connection box (socket outlet), which enables the electrical connection as required. For this purpose, the plug connection unit is provided on a box wall for releasable plug connection to a corresponding plug connection part of a ship supply line, typically a plug (engl. plug). In the interior of the connection box protected against environmental influences, preferably according to protection class IP66 or IP67, a supply line of the land-side supply network is permanently connected to the plug connection unit in the operating state. In addition to the protected wiring of the plug connection unit, the connection box can provide further functions, in particular protective functions.GENERAL DESCRIPTION OF THE FIRST ASPECTIn the first independent aspect, it is proposed according to the invention that at least one explosion pressure relief device is attached to the connection box and / or to the cover part. Preferably, an explosion pressure relief device is provided on each connection box and an explosion pressure relief device is provided on the cover part. Explosion pressure relief devices on the box and on the cover part can in particular be designed largely identically.The explosion pressure relief device, EDEE (Explosion Pressure Relief Device: EPRD) for short, is a design protection measure which primarily prevents explosion pressure in the volume enclosed by the connection box and / or cover part from exceeding the permissible strength of the surrounding walls by blowing pressure through an opening. The explosion pressure relief device is designed to be able to quickly discharge pressure that arises in the event of arc ignition. Thus, the explosion pressure relief device prevents the build-up of explosion pressure, which could lead to major damage, such as an uncontrollable explosion, in particular of the connection box. The explosion pressure relief device can thus considerably reduce the risks of an actual explosion or prevent an explosion in the shore power connection overall.For this purpose, the explosion pressure relief device forms, according to the invention, in particular a predefined relief opening having a predetermined orientation, such that the force or effect of the ignition (arc gases, plasma, melting droplets or particles, pressure wave, etc.) can be diverted away in a controlled manner, in particular into a restricted predetermined external spatial region, outside the shore connection. Thus, the effect of arc ignition can be diverted away from the harbour kai, i.e. also from persons and harbour facility, in order to reduce or minimize resulting risks. In this case, the alignment of the relief opening can correspond in particular to the surface normal to the nominally free opening cross section of the relief opening or can be at least largely parallel thereto. The relief opening preferably has a permanently set and invariable orientation with respect to the geometry of the connection box. The predetermined alignment is understood in particular to mean the resulting main flow direction of emanating explosion gases, for example when considering the spatial distribution in a vertical plane and in a horizontal plane which intersect the relief opening.The structurally selectable, preferably permanently predefined alignment of the relief opening allows - at least largely - a main outflow direction for gases generated by the arc ignition (referred to herein as explosion gases) to be predefined, in particular in a permanently predefinable direction relative to the geometry of the connection box or also to its spatial alignment in the operating position.Preferably, the explosion pressure relief device can have at least one guide body, in particular a guide body arrangement. One or more guide elements can serve as a component of the explosion pressure relief device for the targeted guidance of explosion gases (gases which arise abruptly in the case of arc ignition) through the relief opening and into an outer spatial region, in particular outside the interior of the connection box. Guide elements make possible a more targeted flow guidance, in particular in the interior of the explosion pressure relief device and / or a greater spatial limitation of the spatial region into which the effect of the arc explosion is discharged or dissipated as intended in order to avoid uncontrolled propagation of explosion sequences. A guide body or a guide body arrangement can be designed differently here, for example by geometry of the outer walls and in particular also by inserts or components acting in a flow-guiding manner within the explosion pressure relief device, in particular upstream of the predefined relief opening. The baffle assembly is typically a metal device, which may comprise a number of fins, plates, grids or tubes, and is disposed in the flow path of the exiting gases.The explosion pressure relief device facilitates an explosion pressure-proof construction of the shore power connection. It helps control and mitigate the effects of explosion by safely and predefinedly releasing positive pressure. It can additionally be designed as a type of explosion damper or comprise an explosion damper. In addition to the core function of pressure relief and, if appropriate, explosion damping, it can optionally also prevent the penetration of outside air that could ignite combustible gases, and optionally have means that prevent flame propagation. An explosion damper can be achieved in particular by a suitable guide body arrangement. Generally, the explosion pressure relief is designed to quickly relieve pressure in the event of an explosion, so as to prevent the build-up of critical pressure that could lead to major damage and uncontrolled explosion.In a preferred development, a pressure relief element is attached to the connection box, in particular as a component of the explosion pressure relief device. The pressure relief element is suitable for discharging explosive gases from the interior space under explosion conditions, in particular at a predefined response pressure, and for sealingly closing them under normal operating conditions. At least or only the explosion pressure relief provided on the box side can comprise the pressure relief element. The pressure relief element then releases the predefined relief opening under explosion conditions in order to discharge explosion gases from the interior space of the box through the relief opening and seals the relief opening under normal operating conditions. Such a pressure relief element is not required on the explosion pressure relief device on the cover part, but is optionally possible for the purpose of simplifying the design.The pressure relief element on the connection box is preferably designed as a splash-proof rupture disk or rupture membrane or rupture foil, and can be mounted on the outside of the relief opening, for example, as a component of the explosion pressure relief device, in order to facilitate, for example, assembly, inspection and maintenance. The rupture disk can be advantageously designed as a "disposable product" which breaks under overpressure. Alternatively, an ejection disk can also be provided as a pressure relief element, which is pressed by the pressure from a holder, or an explosion flap or a pressure relief flap can be provided. Advantages of the rupture disk or rupture membrane / rupture foil are, for example, that it can be used independently of position and only brings about low maintenance expenditure. A rupture disk or rupture membrane / rupture foil can also trigger further safety measures, such as an emergency stop, by optional combination with triggering means such as rupture wires or the like. The rupture disk or the pressure relief element is to be selected for optimum protection with the lowest possible static response pressure. It is advantageous if the selected static response pressure can be, for example, <1 bar, in particular ≤0.5 bar, particularly preferably ≤0.25 bar. Preferably, a rupture disk (or rupture membrane or rupture foil) made of stainless material, e.g. of stainless steel, is selected, matching the preferred construction of the connection box made of stainless material, in particular of stainless steel.GENERAL DESCRIPTION OF THE SECOND ASPECTIn the second independent aspect, it is proposed according to the invention that a first cover part and a second cover part are arranged on the connection box, which cover part can be closed to a volume delimited at least to four sides, according to the core of the second aspect, around the connection components or connecting components provided on the outside of the connection box, e.g. plug connectors. The explosion protection can be significantly improved solely by this comparatively simple measure, because arcing can also strike in particular at the outer parts of the connection box or at the connecting plug of the ship supply line. It is to be assumed that the plugs on the ship-side high-voltage line, which are to be used as far as possible during each application process for connection to the shore power interface or the CMS, constitute one of the greatest sources of risk with respect to dangerous arc ignition.The two cover parts serve primarily to delimit, preferably enclose, a volume around the outer connection components which are at risk of arcing. This is also a prerequisite for a preferred explosion pressure relief device according to the first aspect, which is optional for the second aspect but particularly preferred, also being able to be provided for effective explosion protection with respect to the outer connection components.According to the second independent aspect, in order to form a delimited or enclosed volume, at least the first cover part can be movable relative to the connection box, and the two cover parts are configured to fit or correspond or complement one another in this case in order to at least partially cover, in particular enclose, the plug connection unit and a plug connection part which can be plugged thereto in a closed first position, and to release these components in an open second position for releasing or connecting the plug connection. Furthermore, in particular a locking device is provided, by means of which the two cover parts can be locked to one another in the closed first position. As a result, even in the case of explosion pressure, a largely closed volume, a type of limited "plug space", is ensured, with the result that, even without explosion pressure relief device, the effects of arc ignition can be mitigated and / or can be better channeled, for example toward a side which remains open, if the cover parts enclose the connection components at least toward a box wall and toward four sides.The interaction of both cover parts can also realize an access restriction which prevents undesired or detachment of the connection components, for example plug connectors, or enables supplementary monitoring of the access, for example for connection to a safety circuit.The cover parts can preferably be designed as corresponding protective flaps and / or both can be attached to the connection box. However, a separate, removable embodiment of the cover parts or protective flaps is also conceivable. Preferably, both cover parts are movable, e.g. portable, removable or particularly preferably mounted on the connection box.GENERAL DESCRIPTION OF COMMON ASPECTSThe following, further developing features can be applied in principle to both or all aspects of the invention and are each considered separately to be of inventive importance.Preferably, an explosion pressure relief device is provided both on the connection box and on one of the covers, so that the risks of uncontrolled arc explosion in both inner volumes is reduced. In this case, a box-side first explosion pressure relief device with a pressure relief element closing tightly can be provided on the connection box and an open second explosion pressure relief device can be provided on the cover side. It is fundamentally not important whether the cover-side second explosive pressure relief device is provided on the first cover part or on the second cover part, but advantageously both explosive pressure relief devices are arranged with a directivity to the same side.One or each explosion pressure relief device, or the box-side and / or cover-side explosion pressure relief device, can have an explosion damper. This is preferably provided upstream of the relief opening in the outflow direction in order to structurally mitigate the effects of an explosion. The function of the explosion damper can be achieved wholly or partly by a guide body arrangement which at the same time has a flow-directing effect.The at least one explosion pressure relief device preferably has a guide body arrangement which is designed as a cooling and pressure-reducing flow guide device, in particular as a gas-cooling and / or pressure-reducing explosion damper or pressure wave damper. A cooling effect may also reduce flame propagation, if necessary. In addition to a flow-directing effect, the guide body arrangement can also serve as a retaining device against the escape of debris or melt.A suitable guide body arrangement has a plurality of cooling bodies arranged parallel to one another, preferably planar cooling bodies, in particular metal plates in the manner of a parallel plate arrangement. The cooling bodies can preferably be arranged running substantially in a desired main outflow direction and / or substantially parallel to the surface normal of the relief opening or of the maximum possible free opening cross section (e.g. when closed by a rupture disk).The guide body arrangement preferably forms a flow cross section which remains free and is greater than or equal to the opening cross section of the relief opening.The explosion pressure relief device preferably has a modular construction and can be mounted as a preferably prefabricated add-on unit on the connection box or a cover part, in particular on a corresponding connection opening of a box wall or cover wall. The explosion pressure relief devices can each be structurally identical and may only differ from one another by the use of a rupture disk, which may be provided only on the connection box.In a further development, the or each explosion pressure relief device is designed as a hood-shaped add-on unit, with outer walls in which a predefined relief opening with a predetermined orientation is formed, and with a mounting flange surrounding a through-opening for mounting the add-on unit on the outside, adjoining an opening in the connection box or in the cover part, wherein the guide body arrangement is provided in the interior of the add-on unit between the through-opening and the relief opening. The mounting flange can be fastened firmly on the wall of the connection box or cover part.In a structurally favorable embodiment of the explosion pressure relief device, at least two outer walls of the add-on unit are arranged obliquely, in particular trapezoidal or truncated pyramid-shaped, on the mounting flange as a base. Thus, the relief opening can be provided in an inclined outer wall, the angle of which with respect to the mounting flange substantially determines the orientation of the relief flow or a main outflow direction. The orientation of the relief flow can thus be adjusted in terms of design without having to change the connection box or cover part, i.e. suitable for any desired constructions of the connection box.Preferably, the cover parts are designed such that in the first position the plug connection between plug connection unit and plug connection part cannot be released, and the locking device has an interlock bolt which is operatively connected to an electrical switching element, wherein the switching element is electrically connectable or connected to a safety circuit of the ground power supply.The switching element can be electrically connected or connected, in particular, to a safety circuit according to IEC / IEEE 80005-1:2019 (cf. Annex C / Annex D).In principle, the two cover parts are configured to cooperate, particularly preferably such that in the first position, together with at least one housing wall of the connection box, they surround a plug space on all sides in a largely closed manner, in order to reduce the risks of explosion and to enable the installation of an explosion pressure relief device.For this purpose, a constructionally favorable embodiment provides that the cover parts are dimensioned to fit substantially the preferably cuboidal box shape of the connection box and are embodied in cross section, preferably substantially U-shaped, and in longitudinal section, preferably substantially L-shaped. In this case, the cover parts can each be flush with an end region in the first position, in particular sealingly terminate on a housing wall of the connection box.Particularly preferably, the cover parts are designed such that one cover part in the second position engages in an interleaved manner in the other cover part. A mechanically robust design against explosion pressure around the inside is thus achieved.Preferably, both cover parts are movably mounted on the connection box. They can be designed in particular as protective flaps and can be mounted on the connection box between the first and second positions in a manner such that they can be folded open or folded shut.Preferably, both cover parts are coupled by means of a mechanism, in particular a lever mechanism, the movement of both cover parts relative to the connection box. In this case, the connection box can preferably form the frame of the mechanism. To facilitate operation, at least one gas spring can preferably be coupled to the mechanism for support.Preferably, each cover part is mounted on both sides on the connection box at a box-side end region by means of a respective pivot joint.The lever mechanism for movable mounting is preferably designed for coupling the cover parts and / or limiting the maximum pivot angles.Preferably, each cover part has at least one passage recess for a ship supply line at an end region facing away from the box, wherein a sealing element for sealingly bearing against the ship supply line in the first position is preferably provided on the inside of each passage recess.On at least one of the cover parts, an explosion pressure relief device with one or more of the preceding features, in particular according to the first aspect, is preferably provided.The proposed shore power connection enables a relatively compact but more secure construction, in which the cover parts are preferably attached to the closure box as captive components.The shore power connection can be installed in a stationary manner, i.e. in a stationary manner on a portkai. In particular, however, the shore power connection is designed to be movable (mobile shore power outlet).Thus, in a development, the shore power connection is installed movably, in particular is mounted on a positionable support arm and / or is mounted on a movable carriage or carriage.The mobile or stationary shore power connection can preferably be arranged or is arranged in the operating position on a quay facility of a port such that explosion gases in the event of an arc explosion are discharged through the discharge opening of the explosion pressure discharge device away from the quay facility.The connection box and / or the connection components used, in particular the plug connection unit, are preferably designed to be resistant to splash water, preferably according to protection class IP66 or IP67 or higher.The connection box can preferably have at least two plug connection units of identical construction. Two plug connections, in particular according to DIN EN IEC 62613-2:2016, Annex II or IEC / IEEE 80005-1:2019, Chapter 7.3 (Insbes. Annex D.7.3) is advantageous, for example, for the required power for supplying container ships. For larger container ships (6,000-12,000 TEU), the shore power connection should be designed for a connection power of significantly greater than 2 MVA to 6.5 MVA, for which purpose the phase conductors should be distributed over at least two connectors.For an HVSC system, it is preferably provided that the or each plug connection unit of the connection box is designed and configured as a connection socket (socket outlet) for an HVSC system according to requirements of IEC / IEEE 80005-1:2019 and according to DIN EN IEC 62613-1:2016 or DIN EN IEC 62613-2:2016, in particular according to requirements of DIN EN IEC 62613-2:2016, Annex II or IEC / IEEE 80005-1:2019, chapter 7.3.BRIEF DESCRIPTION OF THE FIGURESFurther features and advantages will become apparent, without limiting the foregoing, from the following description of preferred exemplary embodiments of the invention. The following are shown here: FIGS. 1A-1B : show in schematic perspective view a first preferred embodiment of a shore power connection with a connection box and two cover parts in the form of protection flaps movably mounted thereon, shown in the closed position (first position) in FIG. 1A and shown in the open position (second position) in FIG. 1B ; FIGS. 2A-2D : as variants to FIGS. 1A-1B, four further exemplary embodiments of a shore power connection, with cover parts for the protected and largely closed surrounding of the plug-in connection components; FIG. 3 : a first example of application of a shore power connection according to the invention, which is mounted on a feeder carriage that can be moved on the portkai; FIGS. 4A-4B : a second application example of a shore power connection according to the invention, which is mounted on a mast on the portkai in a movable or stationary manner, in a perspective view of the arrangement (FIG. 4A ) and in the open position of the protective flaps (FIG. 4B ) for establishing or releasing the plug connection; FIGS. 5A-5D : a preferred embodiment of a shore power connection with cover parts according to FIGS. 1A-1B which can be folded open as protective flaps, in the closed position (first position), in each case in a perspective view from the outside (FIG. 5A ), in a longitudinal section (FIG. 5B ), in a longitudinal section perspective view, in some cases from below (FIG. 5C ) and in a cross section perspective view through the closed protective flaps (FIG. 5D ); FIGS. 6A-6C show the shore power connection from FIGS. 5A-5D, in a side view of an intermediate position before the closed position (FIG. 6A ), in an enlarged view of the closed position (FIG. 6B : corresponding to the dashed area from FIG. 5B ) and in an enlarged view of the passage for the ship-side supply line (FIG. 6C : corresponding to the dashed area from FIG. 5C ); and FIG. 7 : shows a block diagram of an HVSC system for container ships according to the IEC / IEEE 80005-1:2019 standard as a preferred application of the shore power connection according to the invention.DETAILED DESCRIPTION OF EMBODIMENTSIn the present case, ground current is understood to mean electrical current which is transmitted from a ground-side power supply to a ship, irrespective of the type of ship and the purpose of the supply. In the present case, a nominal voltage of the system in the range from ≥1 kV to 15 kV inclusive or higher is considered as high voltage in the sense of an HVSC system. The rated voltage is typically ≥5 kV and, depending on the ship, for example 6.6 kV, 7.2 kV or 11 kV. The proposed shore power connection can be used particularly advantageously in an HVSC system, in particular for container ships, but not exclusively for this purpose.Purely by way of example, with reference to the block diagram in FIG. 7, the structure and mode of operation of a typical HVSC system for container ships will be explained in principle. Such a system can be divided into two sub-regions. The left portion of the diagram in Figure 7 (left of the dotted line) comprises the landside portion of the land power system, it receives the land power and delivers it to the ship (not shown). The right-hand portion in the diagram of FIG. 7 comprises the on-board distribution network on the deck of the ship. The two subareas are connected via a shore power connection, which is a component of the shore-to-ship interface, typically in the form of a CMS (cf. block 6 at the bottom in FIG. 7 ).FIG. 7 shows, with block 1, a land-side connection to a supply network, for example the local network supplier, which supplies the port or the container terminal. Block 2 represents a landside shore power transformer and a conversion system which converts the shore power voltage into a desired supply voltage to be supplied to the ship, typically e.g. 6.6 kV or 11 kV. Block 2 optionally also comprises a frequency converter in order to provide the desired frequency of the alternating voltage, e.g. 50 Hz or 60 Hz. Block 3 denotes a landside protection circuit which controls protection devices of a switchgear in block 4. In the landside switchgear 4, for example, a (land) circuit breaker and a grounding switch may be provided. The protection devices of the switchgear 4 protect inter alia from abnormal currents, ground fault current etc. for example by a safety shutdown.The system components in blocks 5 to 7 in FIG. 7 comprise a cable management system or a line management system (Engl. Cable Management System), hereinafter abbreviated to CMS, schematically represented by block 6. In this case, the block 6 forms with the CMS a land-ship connection or interface equipment, within which the shore power connection according to the invention is used as intended to connect high-voltage supply cables from the ship to the land-side supply 1, 2 via the switchgear 4.Blocks 5 and 7 represent control means with security functions of the interface equipment. They comprise, for example, a controller for unwinding and winding the flexible high-voltage supply cable and a data interface for communication with the protection circuit 3 of the landside protection devices 4 and with a shipside protection circuit 8 for protection devices in block 9 (see below). The supply lines (not shown) to be connected to the CMS 6, which are used at the interface 6, are generally carried and provided by the ship in the case of a container ship. The control devices 5, 7 can comprise an active control for unwinding and winding the supply lines, which also adjusts during the loading or unloading of the ship and is e.g. also intended to compensate for the tidal stroke.Block number 8 shows the ship's protection circuit which controls the protection devices in the ship's land connection switchgear 9. Block 9 denotes this on-board switchgear, which is installed as a fixed ship installation in a certain room or also in a container or the like, in order to facilitate changing the equipment. The equipment in blocks 8 and 9 correspond to ship-carried equipment for connection to the land connection of the CMS and to the land-ship interface equipment 6, respectively. Block 10 denotes a ship-side isolation transformer connected to an on-board receiving installation, which is part of, for example, the main distribution 11 on board the ship, which feeds an on-board power supply 12 of the ship for loads on board. The main distribution 11 is typically also connected to the on-board generator (not shown). The on-board generator of the ship is to be switched off after connection and synchronization with the ground power supply while the ship is being placed on, for example for loading the containers. The left-hand part region with the blocks 1 to 4 in FIG. 7 is an installation fixedly installed on the port side.The interface area with the blocks 5 to 7, in particular the CMS or the land-ship interface equipment 6, is typically installed at the port side and may comprise moving system components. The right-hand portion of the block diagram in FIG. 7 with the blocks 8 to 12 is carried by the ship to be supplied and is thus variable during operation.A shore power outlet (shore power outlet) is a required major component in the land-to-ship interface equipment 6 of the land power supply system and represents the connection point between the port substation, see block 1-4 in Fig. 7, and the ship's on-board network 12. A shore power connection in the present sense is sometimes also referred to as a shore power box (shore power box).With reference to FIGS. 1-6, preferred exemplary embodiments of a shore power box or shore power connection according to the invention are described in more detail below.FIGS. 1A-1B show, as a first exemplary embodiment, a shore power connection, generally denoted by 20, which is designed and configured for the electrical connection, as required, of the on-board power grid 12 (cf. FIG. 7 ) of a container ship (not shown) and a shore power grid 1 (cf. FIG. 7 ) in an HVSC system (cf. FIG. 7 ). The shore power connection 20 is designed and configured here, by way of example, for three-phase voltage supply at 6.6 kV and a connection power of up to 7.5 MVA.A main component of the shore power connection 20 is the box-shaped housing, referred to herein as a connection box 21 (outlet box), with the desired electrical connections 23A, 23B, in particular HVSC connection boxes (outlet box). The connection box 21 with the HVSC connection boxes 23A, 23B thus forms a detachable connection possibility for corresponding connectors 25A, 25B of the flexible supply lines 27A, 27B for the ship. Only a short portion of the supply lines 27A, 27B is shown schematically in FIGS. 1A-1B. The supply lines 27A, 27B with the plugs 25A, 25B are typically carried by container ships.The connections of the land connection 20 thus comprise one or more plug connection units, in this case in the form of HVSC connection sockets 23A, 23B (also connection sockets), which serve for the detachable plug connection with corresponding ship-side plug connector parts, in this case the HVSC connectors 25A, 25B. The plug connection units provided by the land connection 20 are matched to the electrical requirements of the ship type which is to be supplied, and generally comprise suitable connection sockets 23A, 23B or connection sockets, for container ships, for example designed for a power of typically >2MV, here for example of 3.75MV each. In other ship types, within the scope of the invention, an arrangement with plug-in connection units for plug-in connection other than the one shown here can be provided.For container ships, an arrangement is preferred having two HSVC connection sockets 23A, 23B (socket outlet) of 3.75MVA each, which are designed according to the requirements of the IEC / IEEE 80005-1:2019 (cf. Annex C), chapter 7.3 and of the DIN EN IEC 62613-1:2016 or DIN EN IEC 62613-1:2016.DIN EN IEC 62613-2:2016, in particular Annex II. In the example shown here, exactly two HSVC sockets 23A, 23B are provided for exactly two HVSC plugs 25A, 25B. For other ship types, a different number of HSVC sockets 23A, 23B can be provided, wherein the shore power connection 20 is then dimensioned accordingly or two corresponding connection boxes 21 with two HSVC sockets 23A, 23B each can be provided. For a RoRo ship (cf. IEC / IEEE 80005-1:2019, Annex B), only one plug is required with a connection power of 6.5MV at a rated voltage of 11 kV, for cruise ships 4 plugs are required for a connection power of 16MV.In the example shown, the HVSC connection boxes 23A, 23B, the HVSC connectors 25A, 25B and the supply lines 27A, 27B are designed for three-phase shore current with high voltage, typically, depending on the ship, for example, 6.6 kV, 7.2 kV or 11 kV, and for rated currents corresponding to a nominal supply power of a plurality of MVA, typically, depending on the ship, >2 MVA up to 6.5 MVA or higher. FIG. 4A shows, as preferred HVSC connection boxes 23A, 23B, those according to protection class IP67, with cover and push-pull lever, preferably for 3 phase conductors, neutral conductors, each for at least 200A rated current, and with at least 2 pilot contacts. The HVSC connection boxes 23A, 23B have a corrosion-protected housing, for example made of aluminum alloy.In general, the shore power connection 20 is designed and configured for an HVSC system, i.e. for the electrical connection, as required, of the on-board power network (cf. 12 in FIG. 7 ) of a ship which is placed on the shore, here for example a container ship, to the shore power network (cf. 1 in FIG. 7 ).The connection box 21 serves as a connection point or interface (cf. 6 in FIG. 7 ) and as a housing, in particular for protecting the internal fixed cabling of the connection terminals (cf. FIG. 5C ) of the HVSC connection boxes 23A, 23B with the ground current supply line from the ground-side switchgear 4 (FIG. 7 ). The connection box 21 is accordingly weather-proof and robust and protects electrical components from environmental influences and the personnel from the high voltage. The connection box 21 is designed closed at least according to protection class IP66, preferably protection class IP67, and is suitable for use on a port box 32 (cf. FIG. 4A ) as intended. In the interior of the connection box 21, the HVSC connection boxes 23A, 23B are firmly connected to a supply line (not shown) of the land-side supply network (cf. block 1 in FIG. 7 ).The connection box 21 is preferably substantially designed as a welded metal housing made of stainless steel, preferably made of V4A or CrNiMo steel, designed for high salt water resistance or for rust protection in a maritime environment. In the example according to FIGS. 1A-2D, it has a flat cuboid shape with six substantially rectangular box walls, which enclose an interior space. The connection box 21 is of comparatively compact construction and can be designed in particular as a self-supporting chassis. Thus, the connection box 21 can serve as a mechanical frame and can be fastened at the end, for example, with a fastening end and installed in a cantilevered manner (Engl).As shown in FIGS. 1A-1B, in the preferred embodiment, the terminal box 21 has an upper first cover part 22A and a lower second cover part 22B at an end opposite to the attachment end. The cover parts 22A, 22B are attached at the end side to the connection box 21 and are movably mounted thereon. The two cover parts 22A, 22B serve as protection flaps 22A, 22B in FIGS. 1A-1B.As a comparison of FIGS. 1A and 1B shows, the protective flaps 22A, 22B are movable, preferably foldable, between a first closed position (FIG. 1A ) and an open second position (FIG. 1B ). For this purpose, in FIGS. 1A-1B, each protective flap 22A, 22B is pivotable about an axis A in each case by means of a suitable articulated connection and is mounted on the connection box 21 serving accordingly as a frame. In FIGS. 1A-1B, the axis A lies on the longitudinal sides of the box wall of the connection box 21 with the HVSC connectors 25A, 25B, and runs substantially parallel to the widthwise edges of the connection box 21 there, typically horizontally.FIG. 1A shows the closed operating position. In FIG. 1A, the cover members or protection flaps 22A, 22B surround both the HVSC connection boxes 23A, 23B and the HVSC connectors 25A, 25B in a largely closed manner or surround them. In a preferred embodiment, the protective flaps 22A, 22B surround the plug connectors 23A, 23B and 25A, 25B, respectively, in a largely enclosing manner on all five sides. The sixth side is closed by the terminal box wall of the junction box 21 that supports the junction boxes 23A, 23B. As a result, all plug connectors 23A, 23B and 25A, 25B are on the one hand additionally protected from weather influences and on the other hand also rendered inaccessible during operation, i.e. so that no plug connection can be unintentionally released.FIG. 1B shows the second open position. In FIG. 1B, the opened cover parts or protection flaps 22A, 22B release all HVSC plug connectors, i.e. the HVSC connection boxes 23A, 23B and the HVSC connectors 25A, 25B, so that these can be detached or connected by the operating personnel.The two cover parts 22A, 22B are designed in FIGS. 1A-1B as protective flaps or protective covers which are designed correspondingly or complementarily in the manner of box-shaped cover parts in order to surround a type of plug space with the HVSC connection boxes 23A, 23B and HVSC plugs 25A, 25B in the closed position (FIG. 1A ) as closed as possible. The two cover parts 22A, 22B are thus configured to cooperate so as to substantially enclose such a plug space on all sides in the closed first position (FIG. 1A ), together with a box wall of the connection box 21. In this case, the two cover parts 22A, 22B in the closed position (FIG. 1A ) form a type of closed dismantling or closable / openable widening of the supporting connection box 21 on the box wall with the HVSC connection boxes 23A, 23B. The plug space surrounded by the protective flaps 22A, 22B can surround an inner volume (+ / -33%) which is of similar size compared to the connection box 21.The closable cover parts 22A, 22B together with the connection box 21 simultaneously make possible a significantly improved explosion protection, which is explained in more detail below with reference to FIGS. 5A-5D. According to a core idea, it is sufficient if two cover parts 22A, 22B cooperate correspondingly in order to enclose or enclose the HVSC connection boxes 23A, 23B and the HVSC connectors 25A, 25B connected thereto during operation as largely as possible in a delimited space (connector space) in a closed position (cf. first position in FIGS. 1A, 3, 5A- 5D ). As FIGS. 2A-2D show, it may be sufficient if only one of the two cover parts 22A, 22B is movable relative to the connection box 21.FIG. 2A shows an embodiment of a shore power connection 20A in which the upper cover part 22A is loosely removable and the lower cover part 22B is fixedly mounted on the connection box 21 as intended.FIG. 2B shows a further exemplary embodiment of a shore power connection 20B, in which both cover parts 22A, 22B can be detachably fastened to the connection box 21 and can be removed from the connection box 21. In the closed position, analogous to FIG. 1A, the cover parts 22A, 22B are fixedly but releasably fastened to the connection box 21, for example by a suspension device, locking device or another suitable releasable fastening.FIG. 2C shows a further exemplary embodiment of a shore power connection 20C, in which two cover parts 22A, 22B corresponding to FIGS. 1A-1B are pivotably mounted on the connection box 21 in the form of protective flaps, wherein the pivot axis A in FIG. 2C is also horizontal but substantially in the direction of the plug connection direction or an imaginary longitudinal direction of the shore power connection 20C, i.e. perpendicular to the pivot axis A in FIGS. 1A-1B.FIG. 2D shows, as a further variant to FIGS. 1A-1B, a shore power connection 20D in which both cover parts 22A, 22B are mounted on the connection box 21 in a multiply pivotable manner, for example in each case in a doubly pivotable manner, as protective flaps. The upper cover part 22A is mounted on the lower cover part 22B such that it can be pivoted about a horizontal pivot axis A or parallel to a longitudinal side. The lower cover part 22B is mounted on the connection box 21 on a narrow side about a further horizontal axis B or approximately parallel to the narrow side of the box wall with the HVSC connection boxes 23A, 23B. Thus, the upper cover part 22A can be opened, similar to FIG. 2C, and then pivoted laterally away with the lower cover part 22B in order to release the plug connectors 23A, 23B; 25A, 25B.As the examples from FIGS. 1A-1B and 2A-2D show, both cover parts or protective flaps 22A, 22B are dimensioned to fit substantially a cuboidal design or geometry of the supporting connection box 21. The two cover parts 22A, 22B can be referred to as protective flaps if both are pivotably mounted. The cover parts 22A, 22B can be designed, for example, as box-shaped lid parts open on one side and made of essentially four walls, cf. FIGS. 1A-2D, of which a pair of long side walls are approximately congruent and are perpendicular to a main wall, with a short side wall which terminates perpendicularly to the other and to the main wall. The cover parts 22A, 22B can preferably be substantially U-shaped in cross section and preferably substantially L-shaped in longitudinal section, cf. also FIGS. 2A-2D. In the closed first position or position, both cover parts 22A, 22B close off flush with the open end region, preferably sealingly, in particular in the region of the box wall with the HVSC connection boxes 23A, 23B.From FIGS. 1A-1B and 2A-2D, a further aspect of the invention can only be seen in schematic form, namely a first explosion pressure relief device 41 on the connection box 21 and a second explosion pressure relief device 42 on at least one of the two cover parts 21A, 21B, here on the upper cover part 21A. Preferably, for each of the enclosed cavities, i.e. for the interior of the connection box 21 and for the so-called plug space within the closed cover parts 21A, 21B, a respective separate explosion pressure relief device 41, 42 (hereinafter abbreviated as "EDEE", "explosion pressure relief device": EPRD) is provided.For the interior space in the connection box 21 that is permanently enclosed during operation, the first explosion pressure relief device (EDEE) 41 is provided. For the plug space, which in operation in the closed position (FIG. 1A ) of the protection flaps or cover parts 22A, 22B is largely surrounded by these, the second explosion pressure relief device (EDEE) 42 is provided. The first EDE 41 and the second EDE 42 may be partially different in construction. However, the EDEs 41, 42 are preferably substantially modular to minimize the number of different components.Each of the two EDEs 41, 42 is designed and configured to each form a predefined relief opening 43, 45 (FIG. 1A ) having a predetermined orientation C, D. The EDEs 41, 42 are further each designed and configured for the targeted and controlled discharge of explosive gases from the interior, through the relief opening 43, 45, to the outside into an outer spatial region 49 selected as intended (cf. FIG. 4A ). The term "explosion gases" refers here to those gases which arise in the case of an arc explosion or arc ignition inside the shore power connection 20, 20A..., 20D. The outer spatial region 49 (cf. FIG. 4A ) into which the explosion gases are discharged as intended is determined in particular by the predetermined orientation C, D of the relief opening 43, 45. However, the outer spatial region 49 into which the explosion gases are discharged is also determined in some cases by a structurally predefined directing effect or directional effect of the EDE 41, 42. The EDEs 41, 42 preferably also delimit the respective outer spatial region 49. The directivity of the EDE 41, 42 is set such that, in plan view, the explosion effect is derived only to one side and the other three sides remain protected as far as possible from explosion.Further details on the preferred construction of inventive protective flaps or cover parts 22A, 22B and on the preferred construction of inventive explosive pressure relief devices or EDEs 41, 42 are explained below with reference to FIGS. 5A-5D.FIGS. 3 and 4A-4B show first of all two exemplary, movable variants of a shore power connection 20E, 20F, in each case according to the principle from FIGS. 1A-2D, having two protective flaps 22A, 22B and having a first EDE 41 on a side wall of the connection box 21 and a second EDE 42 on the main wall of the first protective flap 22A. The shore power connection 20E, 20F is preferably mobile, in particular movable along the port passage 32, and can thus be moved to a suitable position along the length of the ship (not shown) to be supplied.In the example from FIG. 3, the shore power connection 20E is mounted for this purpose, for example, on a motorized feeder truck 30 or another freely drivable vehicle. The shore power connection 20 can thus be moved with the feeder carriage 30 inter alia in a longitudinal direction L to the desired position along the port passage 32 (cf. FIG. 4A ) and, when not in use, can be brought into a remote parking position. The feeder carriage 30 carries the connection box 21 in a cantilevered manner at one end. At the other end of the box, the pivotable and pivotable protective flaps 22A, 22B are accessible for operation. Not shown in FIG. 3 is a storage device assigned to the feeder carriage 30 for laying the feeder lines from the fixed supply installation (cf. block 1- 4 in FIG. 7 ) to the shore power connection 20.FIG. 3 also shows, as a possible variant embodiment, a directivity of the two EDEs 41, 42 of the shore power connection 20E that is different from FIGS. 1A-2D. The predetermined orientation C, D of the 43, 45 relief openings of the two EDEs 41, 42 is parallel and, according to FIG. 3, stands in the direction laterally to the shore flow connection 20E, in a direction substantially in a plane perpendicular to the longitudinal direction L. In FIG. 3, the predetermined orientation C, D of the two EDEs 41, 42 is likewise directed towards the sea side or away from the port, but obliquely upwards from the quay surface.The orientation C, D is thus, in FIG. 3, purely by way of example, perpendicular to the longitudinal extent of the shore power connection 20E or to the pivoting plane of the protective flaps 22A, 22B. The alignment C, D can be adjusted in a simple manner by configuring and aligning the EDEs 41, 42 accordingly, here e.g. by fastening the EDEs 41, 42 rotated through 90° relative to the vertical on the junction box 21 or the protective flaps 22A in comparison to FIGS. 1A-2D. For optional alignment, the EDEs 41, 42 preferably have a square basic shape and are fastened by means of a corresponding mounting flange, cf. FIGS. 5A-5D.As best illustrated in FIG. 4A, the EDEs 41, 42 generally permit a predetermined orientation C, D in such a way that explosive gases-in the case of an arc explosion within the connection box 21 and / or within the closed protective flaps 22A, 22B-are conducted in a controlled manner through the relief openings 43, 45 into an non-critical outer spatial region 49, namely away from the port lining 32 (cf. FIG. 4A ), i.e. to the sea or water side. The discharge is effected according to the orientation C, D and preferably into a limited spatial region 49 away from the harbour kai. The spatial region 49 can be limited angularly and is preferably within a spatial angle <180°, preferably <120°, in the vertical plane and within a spatial angle <180°, preferably <120°, in the horizontal plane. The solid angle can be viewed in each case starting from the respective EDE 41, 42, for example in polar coordinates with the respective EDE 41, 42 as the coordinate origin and with the orientation C, D as the bisector, cf. for example FIG. 4A.Such a spatial limitation of the explosion effect of an arc explosion by means of the EDE 41, 42 in combination with the enclosing enclosure by the connection box 21 on the one hand and the cover parts 22A, 22B on the other hand is preferably provided for all exemplary embodiments of the invention and serves for effective protection of personnel and installations in the port or at the port box 32.FIGS. 4A-4B show, in comparison with FIG. 3, a variant of the shore power connection 20F in which the predetermined orientation C, D of the two EDEs 41, 42 is likewise oriented toward the sea side or away from the port, but obliquely downwards toward the sea or toward the water. The orientation C, D can be considered as a vector and, in the case of the shore power connection 20F from FIGS. 4A-4B, lies in a vertical plane, directed obliquely downwards, for example at an angle of approximately 30°-60°, preferably approximately 40°-50°, with respect to the horizontal. The EDEs 41, 42 with their relief openings 43, 45 are designed such that an explosion impact from the EDE 41 that is upper here is conducted as far as possible past the other EDE 42 that is lower here, even in the case of a horizontal orientation (FIG. 5B ). As FIG. 4A shows, the alignment C, D and guiding action of the EDE 41, 42 is selected in each case for all exemplary embodiments such that the action of an arc explosion within the connection box 21, on the one hand, and within cover parts 22A, 22B can be guided away from the harbourkai 32 by the respective EDE 41, 42, preferably into a restricted spatial region 49 in a half space defined by a vertical plane at the shore power connection 20, 20A... 20F.A specific feature of the variant of Figures 4A-4B is a support arm 44 carried by a carriage 46 which is movable in a front guide (not shown) along the kai wall of the portakis 42 to position the shore power connection 20F along the ship. The alignment C, D remains unchanged during the method.From FIGS. 4A-4B, further generally preferred features of the shore power connection 20F are evident, namely a locking device 47A, 47B on the protective flaps 22A, 22B. The locking device 47A, 47B serves to lock the protective flaps 22A, 22B in the closed first position (FIG. 4A ) and, when unlocked, allows their opening. FIG. 4B shows the fully opened second position, in which the protective flaps 22A, 22B release the plug connectors. For the plug connection, HVSC connection boxes 23A, 23B with push-pull lever 24 serve here to facilitate the plug connection, and the HVSC connectors 25A, 25B of the supply lines.To facilitate the opening and closing of the protective flaps 22A, 22B, a lever mechanism 50 is provided, which is explained in more detail with reference to FIGS. 5A and 6A. The lever mechanism 50 and pivotable mounting of the protective flaps 22A, 22B about the pivot axes A is designed such that each protective flap 22A, 22B can be pivoted open by approximately 90°. As FIG. 4B shows, the HVSC sockets 23A, 23B are readily accessible in the open position and their push-pull levers 24 can be easily operated. FIG. 4B also shows a seal 48 on the lower protective flap 22B, in which the upper protective flap 22A engages in the closed position (cf. FIG. 6B ).FIGS. 3 and 4A-4B illustrate, as an advantage of the supporting structure of the junction box 21, the versatility of the shore power terminal 20, 20A... 20F.With reference to FIGS. 5A-5D, a particularly preferred construction of the shore power connection 20 and at the same time further functions or effects and advantages are explained.The construction of the explosive pressure relief devices, EDEs 41, 42 for short, is best seen in Figures 5A-5C. Structurally identical components of both EDEs 41, 42 are provided with identical reference numerals. Each of the two EDEs 41, 42 is designed as a hood-shaped add-on unit and comprises a hood 401 made of metal sheet, in particular of V4A stainless steel, which is fastened, e.g. welded, on a mounting flange 402. The mounting flange 402 is designed as a substantially square metal frame made of metal sheet, in particular made of V4A stainless steel, and forms or surrounds a through-opening 403 to the interior of the EDE 41, 42. Due to its rotationally symmetrical, here square basic shape, the mounting flange 402 can thus be selectively mounted with the through-opening 403 in each case rotated by + / -90° (see also FIG. 3 ) on a corresponding connection opening in the upper box wall of the connection box 21 or the main wall of the protective flap 22A. On the basis of the mounting flange 402, the hood 401 is fixedly screwed on the outside on the edge of the connecting opening, as is best shown in FIG. 5C. A seal 404 may be provided between the mounting flange 402 of the first EDE 41 and the junction box 21 for sealing against water ingress, but is not required on the protective flap 22A in the case of the second EDE. The underside through-opening 403 of the EDE 41, 42 opens through the connection opening open into the interior of the connection box 21 or into the plug space of the cover parts or protective flaps 22A, 22B, as can be seen from FIGS. 5B-5C.As FIG. 5B shows, the hood 401 is each designed such that its outer walls form a shape of an isosceles trapezium in cross section (vertically), the long base side being open and bordered by the mounting flange 402 (FIGS. 5A / 5C ).The hoods 401 each form, in one, in particular in exactly one, side wall 405, at least one predefined relief opening 43, 45 with a predetermined orientation C, D. The orientation C, D is determined structurally by the geometry of the hood 401, i.e., here in particular determined by the internal angle between the inclined side wall 405 and the base surface or the plane of the mounting flange 402. This angle is illustrated as angle of attack α in FIG. 5B. Thus, the orientation C, D can be constructively adjusted by the corresponding angle of attack α of the side wall 405.A difference of the first EDE 41 from the second EDE 42 is that the relief opening 43 of the first EDE 41 is closed in a watertight manner by a rupture disk 411 as a pressure relief element in the new state or in the normally operational state, wherein a circumferential seal is preferably provided between the rupture disk 411 and the edge of the side wall 405 which surrounds the passage opening 45. The rupture disk 411 is preferably made of thin stainless steel sheet and is selected with low static response pressure, in particular ≤0.5 bar, particularly preferably ≤0.25 bar. Alternatively, another pressure relief element can also be used, e.g. a rupture membrane or rupture foil made of plastic. The rupture disk 411 is mounted on the outside of the main on the side wall 405 and is thus easily accessible for inspection and replacement. In order to mechanically protect the rupture disk 411 against unwanted damage, a protective grille 413 is also attached to the hood 401 of the first EDE 41.In the second EDE 42, on the other hand, the through-opening 45 does not have to be closed in a watertight or water-resistant manner, since the plug connectors, i.e. here HVSC connection socket 23A, 23B and HVSC plug 25A, 25B, are already designed in a suitable protection class, e.g. IP67, in a water-resistant manner. Therefore, in contrast to the dense rupture disk 411 of the first EDE 41, the second EDE 42 is provided with only one open grid, e.g. as perforated plate 412, or the like, in order to achieve a certain mechanical protection and, if applicable, a pressure damping.Both the rupture disk 411 of the EDE 41 and optionally the perforated sheet 412 of the EDE 42 may act as a pressure relief element. However, the rupture disk 411 of the EDE 41 releases the relief hole 43 inside the terminal box 21 under explosion conditions. However, the perforated plate 412 serves primarily as a mechanical protection against the entry of undesired foreign bodies.The first EDE 41 and second EDE 42 are of identical construction in turn with regard to a guide body effect and guide body arrangement 420, which is provided in the interior of the add-on unit or the hood 401 between the through-opening 403 and the relief opening 43 or 45. In each EDE 41, EDE 42, a guide body arrangement 420 is provided, which comprises a primary gas-cooling and pressure-reducing explosion damper 422 comprising a plurality of cooling bodies arranged parallel to one another, here in the form of a parallel plate arrangement as explosion damper 422 with a plurality of thin-walled metal plates 424 or metal plates arranged parallel, which are held parallel via cross struts 426 and intermediate spacer plates as spacer elements, as can be seen from FIGS. 5B-5C. The guiding action of the guide body arrangement 420 is also contributed by the geometry of the hood 401 with its side walls. The explosion dampers 422 are fastened on the mounting flange 402 by means of the cross struts 426, for example on the end side via fastening elements, such that each EDE 41, 42 can be mounted as a prefabricated add-on unit on the connection box 21 or a protective flap 22A, 22B and can optionally be exchanged.The explosion damper 422 of both the EDEs 41, 42 is configured such that the metal plates 424 function as heat sinks to absorb thermal energy from explosion gases and to lower the temperature of the explosion gases, respectively. The metal plates 424 are preferably arranged running substantially in the main outflow direction C, D or in the cross-sectional plane of FIG. 5B, i.e. substantially parallel to the surface normal of the relief opening 43, 45. Preferably, the flow cross section remaining free between the metal plates 424 is greater than or equal to the opening cross section of the relief opening 43 or 45 by selecting the spacer elements in order not to cause any back pressure. By virtue of the parallel metal plates 424, the explosion damper 422 may affect the flow of gas passing therethrough, here explosion gas in the event of arc explosion, and generate an at least partially laminar flow under certain conditions. Furthermore, due to the parallel metal plates 424, the explosion damper 422 has a flow-guiding effect in such a way that the expansion of the explosion gas before and in particular also after exiting through the relief opening 43 or 45 in the direction perpendicular to the plane of FIG. 5B is reduced. Due to the parallel metal plates 424, the explosion damper 422 also causes a pressure drop over the flow path from the through-opening 403 to the respective relief opening 43 or 45, i.e. in the interior of the respective hood 401 and thus within EDE 41 or EDE 42. This pressure drop arises primarily by thermal energy absorption or cooling of the explosion gas in the explosion damper 422 so that plates with high thermal conductivity, e.g. metal plates 424, are advantageous. The pressure drop can also be increased by flow effects and in this case depends on factors such as the gap width between the metal plates 424, the inner volume of the hoods 401, and the cross sections of the relief opening 43 or 45 on the one hand and of the passage opening 403 on the other hand. The pressure drop or the pressure relief can thus be structurally influenced.By means of the EDEs 41 and 42, in particular the explosion dampers 422, harmful explosion effects can be significantly reduced in that a limitation of the spatial effect outside the shore flow connection 20 on the one hand and a perceptible pressure relief within the EDEs 41, 42 is achieved, in particular by gas cooling. The explosion dampers 422 are preferably provided in the same construction in both EDEs 41, 42. The preferred arrangement within the hoods 401 mechanically protects the explosion dampers 422 from damage. The relief openings 43, 45 also have an influence on the gas flow as orifice openings of the EDE 41, 42 for the gas outward discharge. For a spatial confinement of the outer spatial region 49 in the explosion gases and the explosion pressure wave are derived from the EDEs 41, 42, in particular in the direction perpendicular to the longitudinal section of the connection box 41 or perpendicular to the plane of FIG. 5B, it is advantageous if the geometry of the relief openings 43, 45 in the side walls 405 is substantially rectangular, oval, long round or similar and is selected such that an aspect ratio (or from long axis to short axis) of length:width≥2:1 (is predetermined. The width can be between 100 mm and 300 mm, for example, and the length corresponding to 200 to 600 mm, depending on the size of the connection box 21, For the most identical possible flow conditions or guiding effect, it is advantageous if the internal volume of the connection box 21 and of the closed protective flaps 22A, 22B deviates from one another only insignificantly, for example by less than ≤ 20%, cf. FIGS. 5A-5D. The relief openings 43, 45 should have an opening cross section of at least 10% of the smallest cross section of the inner volume (perpendicular to the plane from FIG. 5B ) from the plug space within protective flaps 22A, 22B or inner space of the connection box 21 in order to achieve a rapid pressure reduction in the event of arc explosion. The free cross section of the through-opening 403, which is preferably defined by the mounting flange 402, from the interior or plug space to the interior of the EDE 41, 42 should preferably be significantly larger than the opening cross section of the relief openings 43, 45, as can be seen from FIGS. 5B-5C.Practical tests have shown that arc ignition in the plug space inside protective flaps 22A, 22B typically propagates into the interior of the connection box 21 and vice versa, so that it is particularly advantageous to provide an EDE 41, 42 both on the connection box 21 and on one of the protective flaps 22A, 22B, as can be seen in FIG. 5B, for example. However, an embodiment variant with only one EDE 41, 42 and a passage opening under explosion pressure between the plug space and the interior space of which is closed, for example, by means of a suitably dimensioned rupture disk (not shown), would also be conceivable, in order to make it possible to relieve it from the other space in the event of arc ignition.With reference to FIGS. 5A-5D, further details of a preferred mounting of the cover parts or protective flaps 22A, 22B on the connection box 21 are explained. The cover parts or protective flaps 22A, 22B are each mounted freely projecting on one side on the connection box 21, here by means of a hinge-like pivot mounting which defines the pivot axes A of the protective flaps. For this purpose, on both sides, symmetrical and in each case for each protective flap 22A, 22B, two hinge elements 501 are provided on the connection box 21, which elements bear and hold a common hinge axis 502. On the upper hinge axis 502, a hinge arm 503A for the first protective flap 22A is provided symmetrically on both sides, by means of which hinge arm the protective flap 22A is mounted on the connection box 21 so as to be pivotable about the axis A. Analogously, a hinge arm 503B for the second protective flap 22A is provided symmetrically on both sides on the lower hinge axis 502, by means of which hinge arm the protective flap 22B is mounted on the connection box 21 such that it can pivot about the axis A. The arrangement is designed such that the protective flaps 22A, 22B can be pivoted upwards or downwards, for example, by a respective angle of slightly 90° (cf. also position in FIG. 4B ), wherein the pivot angle can be adjusted via the dimensioning of the components, for example hinge arms 503A, 503B. In the preferred embodiment, the cover parts form protective flaps 22A, 22B which are mounted on the connection box 21 in such a way that they can be opened or closed via the hinge axles 502 in each case between a first closed position (FIGS. 5A-5B ) and a second position (cf. FIG. 4B ). The protective flaps 22A, 22B are mounted on the connection box and held in a cantilevered manner or supported on one side by means of the respective pivot joint comprising two hinge elements 501, a hinge axis 502 and two hinge arms 503A and 503B, respectively.Due to the dead weight of the protective flaps 22A, 22B together with the add-on parts such as EDEs 41, 42 etc. and for easier handling, a lever mechanism 50 is provided which mechanically couples the pivoting movement of the protective flaps 22A, 22B to one another. For this purpose, the hinge arms 503A, 503B each have extensions which are designed as lever arms 505A, 505B and which are coupled to one another in a driven manner via a coupling rod 506, so that, when the upper protective flap 22A, for example, is pivoted, the lower protective flap 22B correspondingly automatically also pivots. For ease of operation and for holding in the open second position, the lever mechanism 50 comprises a respective spring, for example a damping gas spring 507, on each side, which spring is coupled to the coupling rod 506. The gas spring 507 prevents, among other things, an undesired closing of the protective flap 22A or 22B. The self-supporting connection box 21 forms the frame for the lever mechanism 50, which couples the movement of both cover parts. The parameters of the lever mechanism and, among other things, the maximum pivot angle can be set via the lever lengths of the lever arms 505A, 505B on the hinge arms 503A, 503B, so that, for example, different pivot angles can also be set by translation.As can best be seen from FIGS. 5D and 6A, a locking device 510 is furthermore provided, by means of which the two cover parts or protective flaps 22A or 22B can be locked in the closed first position. At the free end of the protective flaps 22A and 22B, opposite the hinge axes 502, a locking axis 512A and 512B is provided for this purpose, each passing transversely through each protective flap 22A and 22B. On the upper locking axis 512A of the protective flap 22A, a respective locking lever 514 is arranged on both sides on the outside in a rotationally fixed manner, so that these are mounted on the protective flap 22A in a robust and pivotable manner with the locking axis 512A. An operation lever 513 is provided on at least one of the lock levers 514. Each locking lever 514 forms a locking hook 515 on the end side, which in the closed position (FIG. 5D ) engages behind the other locking axis 512B of the other protective flap 22B. In the engaged position, the two lateral locking hooks 515 thus engage the other locking pin 512B, which is rigidly connected to the protective flap 22B. In this position, the protective flaps 22A, 22B cannot be opened and are closed in an explosion-proof manner. For additional safety, a locking bolt 520 (also an interlock bolt) is provided, which can be opened and closed only in the locked position (FIG. 5D ), by releasable engagement in a locking opening in the protective flap 22B (cf. FIG. 5D ). An electrical switching element 522 is operatively connected to the one interlock bolt or locking bolt 520, which electrical switching element is electrically connectable or connected to a safety circuit of the ground power supply.As can be seen from FIGS. 5A-5D, the cover parts or protective flaps 22A, 22B are designed such that, in the closed first position, the plug connection between the plug connection unit, i.e. here the HVSC connection box 23A, 23B, and the plug connection parts, i.e. here the HVSC connectors 25A, 25B, cannot be released. The locking achieves additional safety, which also ensures explosion-proof closing of the protective flaps 22A, 22B. In addition, an interlock function can be connected via the switching element 522 to the pilot loop of the safety circuit of the HVSC system from FIG. 7. In this way, conventional Kirk-Key Locks can be avoided. The pilot loop monitors the correct connection of plug connections in the high-voltage circuit with the aim of preventing an electrical risk due to unintentional, improper or otherwise caused disconnection of an HV plug connection when the HV system is active. In order to achieve this, the locking mechanism 510 with the locking bolt 520 and the electrical switching element 522 can be integrated signal-wise into the so-called pilot line or also safety line.FIGS. 5A-5D also each show a circumferential seal 48 at the open edges of the protective flaps 22A, 22B, which is explained in more detail with reference to FIG. 6B. The seal 48 is provided at the open edge of the protective flaps 22A, 22B, respectively. Here, the circumferential edge 532A of the upper protective flap 22A is bent or deformed outwards and the circumferential edge 532B of the lower protective flap 22B is bent outwards. The upper protective flap 22A engages in the lower protective flap 22B during the closing process (cf. FIG. 6A ). This allows a sealing closure in that the seals 48 come into contact or the one protective flap 22A or 22B abuts the seal of the other protective flap 22A or 22B in the closed position. In addition, in the event of explosion in the connector space inside the closed protection doors 22A and 22B, the inwardly formed edge 532A of the protection door 22A is pressed outwardly against the other protection door 22B to enhance the sealing effect and to contain the explosion.Finally, FIG. 6C shows, in each case on the free front side of the edge 532A or 532B of each protective flap 22A, for each plug connection, a passage cutout 530 for passage of each ship supply line 27A, 27B (not shown in FIG. 6C ) of the two HVSC connectors 25A, 25B (cf. FIG. 2D, for example). Here, on the upper protective flap 22A, on the inside of the passage recess, an additional sealing element 533 is provided for sealingly bearing against the ship supply line 27A, 27B, which can be adapted to the desired line diameter by means of an adjustment plate 534. A half-shell-shaped abutment 535 is provided on the other protective flap 22B, so that, when the position is closed, the ship supply lines 27A, 27B can be clamped or rest tightly between the protective flaps 22A, 22B.As can be seen from FIGS. 2A-2D and also FIGS. 5A-5D and 6C, the passage recesses 530 are aligned with the axis of the HVSC sockets 23A, 23B and the protective flaps 22A and 22B are designed such that the joining plane or interface is approximately aligned with the axis of the HVSC sockets 23A, 23B, which facilitates the handling of the heavy ship supply lines 27A, 27B for the operator.Finally, it should be stated in summary that the proposed shore power connection improves the safety, in particular the protection of personnel, in several respects. Safety should be the first place in shore power systems, in particular HVSC systems.List of reference charactersFIGS. 1A-1B, 2A-2D ; FIGS. 3-4 20 Shore power connection 20A, 20B, 20C, 20D, 20E, 20F Shore power connection (variants) 21 Connection box 22A, 22B Cover part or protective flap 23A, 23B HVSC connection box (socket outlet) 24 Push-pull lever 25A, 25B HVSC plug 27A, 27B Supply line 30 Feeder carriage 32 Hafenkai 41, 42 Explosion pressure relief device (cover: EDE) 43, 45 Relief opening 44 Support arm 46 Carriage (movable on the Hafenkai) 47A, 47B Locking device 48 Seal 49 Outer seal, Limited spatial area 50 Lever mechanism A, B Pivot axes (of the protective flaps) C, D Direction of alignment (of the EDEE) L Longitudinal direction / travel directionFIGS. 5A-5D, 6A-6C 20 shore power connection 21 connection box 22A, 22B protection flap 23A, 23B HVSC connection box (socket outlet) 41, 42 explosion pressure relief device (Abk.: EDEE) 43, 45 relief opening 48 seal 50 lever mechanism 401 hood 402 mounting flange 403 through opening 404 seal 405 oblique side wall (with through opening) 411 rupture disk 412 perforated plate 413 protection grid 420 guide body arrangement 422 explosion damper 424 metal plates 426 cross struts 501 hinge elements 502 hinge axis 503A, 503B hinge arm 505A, 505B lever arm 506 coupling rod 507 gas spring 510 locking device 512A, 512 block axle 513 actuating lever 514 locking lever 515 locking hook 520 locking bolt 522 switching element 530 passage recess 532A, 532B circumferential edge 533 sealing element 534 adjusting plate 535 abutmentFIG. 7 (typical HVSC system) 1 connection to the supply network 2 land-side transformer, optionally with frequency converter 3 land-side protection circuit 4 land-side switching system (circuit interrupter, grounding switch, etc.) 5 controller 6 land-ship interface equipment / CMS 7 controller 8 protection circuit for the ship 9 land connection switching system 10 on-board isolation transformer 11 on-board reception circuit 12 on-board network on the container shipReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedWO 20202 / 16818 A1 [0011, 0014, 0015]CN 109103783A

[0013] DE 20 2014 105 940 U1

[0097] Cited Non-Patent LiteratureEuropean Maritime Safety Agency: Shore-Side Electricity-Guidance to Port Authorities and Administration, Part 2-Planning, Operations and Safety, Version 2, August 2022-cf. Chapter 9

[0006]

Claims

Shore power connection (20) for supplying a ship, wherein the shore power connection (20) is designed and configured for the electrical connection, as required, of the on-board power grid (12) of a fitted ship, in particular of a container or cruise ship, and of a shore power grid (1), in particular designed and configured for the purpose of polyphase voltage supply at at least 6.6 kV or 7.2 kV and / or at at least 2 MVA connection power, wherein - the shore power connection comprises a connection box having box walls which enclose an interior space, wherein the connection box comprises at least one plug connection unit, in particular a connection box, which is provided on a box wall for releasable plug connection to a corresponding plug connection part, in particular a plug, of a ship power line and can be fixedly connected in the interior space of the connection box to a feed line of the shore power grid, and - the shore power connection comprises at least one cover part which can be moved relative to the connection box and at least partially covers the plug connection unit and a plug connection part which can be plugged thereto in a first position and releases said plug connection in a second position for releasing or connecting the plug connection, characterized in that at least one explosion pressure relief device is attached to the connection box and / or to the cover part, preferably in each case to the connection box and to the cover part, and in that - the explosion pressure relief device forms a predefined relief opening having a predetermined orientation, and - the explosion pressure relief device preferably has at least one guide body, in particular a guide body arrangement, for guiding explosion gases which arise in the event of an arc explosion, through the relief opening and into an outer spatial region.Shore power connection according to Claim 1, characterized in that a pressure relief element is attached to the connection box in order to discharge explosive gases from the interior space under explosion conditions, in particular at a predefined response pressure, and to seal them in a sealing manner under normal operating conditions.Shore flow connection according to Claim 2, characterized in that at least one explosion pressure relief device comprises the pressure relief element and is attached to the connection box on the box side, wherein the pressure relief element opens up the predefined relief opening under explosion conditions in order to discharge explosion gases from the interior through the relief opening, and / or the pressure relief element is designed as a splash-proof rupture disc or rupture membrane.Shore power connection according to claim 1, 2 or 3, characterised in that the shore power connection comprises the first cover part which is movable relative to the connection box and a second cover part, wherein the cover parts are designed to be corresponding or complementary and cooperate, preferably lockable, in order to enclose the plug connection unit and a plug connection part which can be plug-connected thereto at least to four sides, and a locking device is provided by means of which the two cover parts can be locked in the first position.Shore power connection according to one of the preceding claims, in particular according to Claim 4, characterized in that a box-side first explosion pressure relief device with a pressure relief element closing tightly is provided on the connection box, and an open second explosion pressure relief device is provided on the cover side, wherein the cover-side second explosion pressure relief device is provided on the first cover part or on the second cover part.Shore connection according to one of the preceding claims, characterized in that the box-side and / or cover-side explosion pressure relief device has an explosion damper which is provided upstream of the relief opening in the outflow direction.Shore connection according to claim 6, wherein the guide body arrangement comprises a gas-cooling and / or pressure-reducing explosion damper.Shore power connection according to one of Claims 1 to 7, in particular according to Claim 7, characterized in that the guide body arrangement comprises a multiplicity of cooling bodies arranged parallel to one another, preferably planar cooling bodies, in particular metal plates in the manner of a parallel plate arrangement, - which are preferably arranged running substantially in the main outflow direction and / or substantially parallel to the surface normal of the relief opening, and / or - which preferably form a flow cross section which remains free and is greater than or equal to the opening cross section of the relief opening.Shore power connection according to one of the preceding claims, characterized in that the or each explosion pressure relief device is designed as a hood-shaped add-on unit, having outer walls in which a predefined relief opening with a predetermined orientation is formed, and having a mounting flange surrounding a through-opening for mounting the add-on unit on the outside, adjoining an opening in the connection box or in the cover part, wherein the guide body arrangement is provided in the interior of the add-on unit between the through-opening and the relief opening.Shore flow connection according to Claim 9, characterized in that in the explosion pressure relief device, at least two outer walls of the add-on unit are arranged obliquely, in particular trapezoidal or truncated pyramid-shaped, on the mounting flange as a base, and the relief opening is provided in an obliquely arranged outer wall, the angle of which with respect to the mounting flange substantially determines the orientation of the relief flow or a main outflow direction.Shore power connection for supplying a ship, wherein the shore power connection is designed and configured for the required electrical connection of the on-board power network of a fitted ship, in particular of a container or cruise ship, and a shore power supply network, in particular designed and configured for the purpose of polyphase voltage supply at at least 6.6 kV or 7.2 kV and / or at at least 2 MVA connection power, wherein - the shore power connection comprises a connection box having box walls which enclose an interior space, in particular in a spray-water-proof manner, - the connection box comprises at least one plug connection unit, in particular a connection box, which is provided on a box wall for the detachable plug connection to a corresponding plug connection part of a ship power supply line and can be fixedly connected in the interior space of the connection box to a feed line of the shore power supply network, characterized in that, a first cover part and a second cover part are provided, wherein at least the first cover part is movable relative to the connection box, and wherein the cover parts are designed to be corresponding or complementary in order to at least partially cover, in particular at least to four sides, the plug connection unit and a plug connection part which can be plugged thereto in a first position, and to release said connection in a second position for releasing or connecting the plug connection, and a locking device is provided by means of which the two cover parts can be locked on the connection box in the first position.Shore power connection according to Claim 11, characterized in that the cover parts are designed in such a way that, in the first position, the plug connection between the plug connection unit and the plug connection part cannot be released, and the locking device has an interlock bolt which is operatively connected to an electrical switching element, wherein the switching element is electrically connectable or connected to a safety circuit of the shore power supply.Shore power connection according to claim 4 or according to any one of claims 11 to 12, characterised in that the cover parts are configured to cooperate in order, in the first position, to enclose a plug space largely closed on all sides together with at least one wall of the connection box.Shore power connection according to Claim 4 or according to one of Claims 11 to 13, characterized in that - the cover parts are dimensioned to fit substantially the preferably cuboidal box shape of the connection box and are of a cross section, preferably substantially U-shaped, and of a longitudinal section, preferably substantially L-shaped, in order in the first position to be flush with an end region, in particular to be sealingly closed off on a housing wall of the connection box, and / or - a cover part engages in the other cover part in a nested manner in the second position.Shore power connection according to Claim 4 or according to one of Claims 11 to 14, characterized in that both cover parts are mounted movably on the connection box, in particular are designed as protective flaps and are mounted on the connection box such that they can be opened or closed between the first and second positions, and / or a mechanism, in particular a lever mechanism, couples the movement of both cover parts relative to the connection box and wherein the connection box preferably forms the frame of the mechanism and / or wherein preferably at least one gas spring is coupled to the mechanism for support.Shore power connection according to claim 15, characterised in that each cover part is mounted on both sides on the connection box at an end region on the box side by means of a respective pivot joint.Shore power connection according to claim 4 or according to one of claims 11 to 16, characterised in that each cover part has at least one passage recess for a ship supply line at an end region facing away from the connection box, wherein a sealing element for sealingly bearing against the ship supply line in the first position is preferably provided on the inside of each passage recess.Shore power connection according to one of Claims 12 to 18, characterized in that at least one explosion pressure relief device, in particular according to at least one of Claims 1 to 4 or 6 to 9, is provided on the first cover part or on the second cover part.Shore power connection according to one of the preceding claims, characterized in that the shore power connection - is installed movably, in particular is mounted on a positionable support arm and / or is mounted on a movable carriage or a carriage; and / or - in the operating position is arrangeable or arranged on a quay installation of a port such that explosive gases are discharged away from the quay installation through the relief opening of the explosive pressure relief device in the event of an arc explosion.Shore power connection according to one of the preceding claims, characterized in that the connection box and / or the plug connection unit is or are designed to be resistant to splashing water, preferably according to protection class IP67 or higher.Shore power connection according to one of the preceding claims, characterized in that the connection box has at least two plug connection units of identical construction, and / or the or each plug connection unit of the connection box is designed and configured as a connection box for an HVSC system IEC / IEEE 80005-1:2019, in particular according to requirements of DIN EN IEC 62613-1 and DIN EN IEC 62613-2.Land-to-ship interface equipment, in particular for an HVSC system of a container terminal, comprising a shore power connection according to at least one of the preceding claims 1 to 21.

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