Ship shore power connection circuit and disconnector box

Abstract

The present invention relates to a ship shore power connection circuit and an isolating switch box, wherein the ship shore power connection circuit comprises a busbar whose output end is connected to a shore power box and input circuits connected to corresponding shore power cables; the input circuit comprises a switch module, a cable input end and a phase difference detection module connected to the switch module; the cable input end is connected to the busbar through the switch module and the phase difference detection module respectively; when the phase difference detection module detects that there is a phase difference between the busbar and the cable input end, the switch module is controlled to disconnect from the busbar, thereby solving the problem of phase-to-phase short circuit fault when the shore power line is powered on due to wrong connection during the ship shore power cable connection process, thereby ensuring the safety of shore power use.

Description

Technical Field

[0001] The invention relates to the technical field of ship shore power, in particular to a ship shore power connection circuit and an isolating switch box. Background Art

[0002] When a ship obtains power from external power distribution devices such as dock distribution boxes, external power supply facilities of other ships or offshore platforms, the external power supply is usually connected to the ship's distribution system through the ship's shore power connection system; when the ship requires a large external power capacity, it is usually necessary to configure two or more shore power cables, and the shore power cables are used in parallel to meet the maximum capacity requirements of the ship's shore power operating conditions.

[0003] During the implementation process, the inventors found that there are at least the following problems in the traditional technology: when two or more shore power cables are used at the same time, the phase sequence is easily misconnected, resulting in inconsistent phases of the current-carrying core wires in the cables used in parallel, causing phase-to-phase short-circuit faults in the shore power lines, posing a hidden danger to electricity use. Summary of the invention

[0004] Based on this, it is necessary to provide a ship shore power connection circuit and an isolating switch box to address the problem that the shore power cables in the shore power connection system are easily connected in the wrong phase sequence and there are hidden dangers of electricity use.

[0005] In order to achieve the above-mentioned object, on the one hand, an embodiment of the present invention provides a ship shore power connection circuit, including a busbar whose output end is connected to a shore power box and input circuits connected to corresponding shore power cables;

[0006] The input circuit includes a switch module, a cable input end, and a phase difference detection module connected to the switch module; the cable input end is connected to the bus through the switch module and the phase difference detection module respectively;

[0007] When the phase difference detection module detects that there is a phase difference between the bus and the cable input end, the phase difference detection module controls the switch module to disconnect the cable input end from the bus.

[0008] In one of the embodiments, the phase difference detection module is a voltage difference detection unit;

[0009] When the voltage difference detection unit detects that there is a voltage difference between the bus bar and the cable input end, the voltage difference detection unit controls the switch module to disconnect the cable input end from the bus bar.

[0010] In one embodiment, the first phase port of the cable input end is connected to the first phase circuit of the bus through the switch module, and the second phase port is connected to the second phase circuit of the bus through the switch module;

[0011] The phase difference detection module includes a first relay and a second relay;

[0012] One end of the coil of the first relay is connected to the first phase circuit of the bus, and the other end is connected to the first phase port of the cable input end; when there is a phase difference between the first phase circuit and the first phase port, the first relay controls the switch module to disconnect the cable input end from the bus;

[0013] One end of the coil of the second relay is connected to the second phase circuit of the bus, and the other end is connected to the second phase port of the cable input end; when there is a phase difference between the second phase circuit and the second phase port, the second relay controls the switch module to disconnect the cable input end from the bus.

[0014] In one embodiment, the switch module includes a circuit breaker and a pressure loss tripping coil connected to the phase difference detection module and the circuit breaker;

[0015] One end of the circuit breaker is connected to the busbar, and the other end is connected to the cable input end;

[0016] When the phase difference detection module detects a phase difference between the bus and the cable input end, it controls the undervoltage release coil to cut off the power and the circuit breaker to disconnect the cable input end from the bus.

[0017] In one of the embodiments, the input circuit further includes a power detection module connected to the cable input end, the switch module, and the phase difference detection module;

[0018] When the power detection module detects that the cable input end is powered off, it disconnects the switch module, the phase difference detection module and the bus.

[0019] In one embodiment, the power detection module includes a third relay;

[0020] One end of the coil of the third relay is connected to the first phase port of the cable input end, and the other end is connected to the second phase port of the cable input end; the switch module and the phase difference detection module are connected to the bus through the normally open contact of the third relay;

[0021] When the third relay detects that the cable input end is powered off, the normally open contact of the third relay is controlled to disconnect the switch module, the phase difference detection module and the bus.

[0022] In one embodiment, the input circuit includes a first input circuit connected to a first shore power cable and a second input circuit connected to a second shore power cable;

[0023] The first input circuit includes a first power supply control module connected to a cable input terminal of the first input circuit, a switch module, and a phase difference detection module;

[0024] The second input circuit includes a second power supply control module connected to a cable input end of the second input circuit, a switch module, and a phase difference detection module;

[0025] The first power control module is connected to the second power control module;

[0026] When the cable input end of the first input circuit is powered on, the first power control module controls the switch module and the phase difference detection module of the first input circuit to connect to the bus, and controls the second power control module to disconnect from the cable input end, the switch module and the phase difference detection module of the second input circuit.

[0027] In one of the embodiments, when the cable input end of the first input circuit is powered off and the cable input end of the second input circuit is powered on, the second power supply control module controls the switch module and the phase difference detection module of the second input circuit to connect to the bus, and controls the first power supply control module to disconnect from the cable input end, the switch module, and the phase difference detection module of the first input circuit.

[0028] In one of the embodiments, the second input circuit further includes a time delay relay connected to the cable input end of the second input circuit;

[0029] The second power supply control module is connected to the cable input end of the second input circuit through the normally open contact of the time delay relay;

[0030] When the cable input end of the first input circuit and the cable input end of the second input circuit are both powered on, the first power supply control module controls the switch module and the phase difference detection module of the second input circuit to connect to the bus, and controls the second power supply control module to disconnect the second power supply control module from the cable input end of the second input circuit through the time delay relay.

[0031] On the other hand, an embodiment of the present invention further provides an isolating switch box, which includes the above-mentioned ship shore power connection circuit.

[0032] One of the above technical solutions has the following advantages and beneficial effects:

[0033] When the phase difference detection module detects a phase difference between the bus connected to the shore power box and the input circuit connected to the shore power cable, the control switch module disconnects the cable input end from the bus; this solves the problem of phase-to-phase short circuit failure when the shore power line is energized due to wrong connection during the connection of the ship's shore power cable, thereby ensuring the safety of shore power use. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The above and other purposes, features and advantages of the present invention will become more clear through the more specific description of the preferred embodiments of the present invention shown in the accompanying drawings. The same reference numerals indicate the same parts in all the accompanying drawings, and the accompanying drawings are not deliberately scaled to the actual size, and the focus is on illustrating the main purpose of the present invention.

[0035] Figure 1This is a schematic diagram of the structure of the traditional technology ship shore power connection system;

[0036] Figure 2 This is a first schematic structural diagram of Embodiment 1 of a ship shore power connection circuit of the present invention;

[0037] Figure 3 This is a primary circuit structure diagram of an example of a ship shore power connection circuit of the present invention;

[0038] Figure 4 The first structural diagram of the control circuit of the ship shore power connection circuit example of the present invention;

[0039] Figure 5 It is a second schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention;

[0040] Figure 6 is a third schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention;

[0041] Figure 7 is a fourth schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention;

[0042] Figure 8 is a fifth schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention;

[0043] Fig. 9 is a sixth schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention;

[0044] Fig.10 is a seventh schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention;

[0045] Fig.11 is an eighth schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention;

[0046] Fig.12 The second structure diagram of the control circuit of the ship shore power connection circuit of the present invention

[0047] Fig.13 This is a first schematic structural diagram of the isolating switch box embodiment 1 of the present invention. DETAILED DESCRIPTION

[0048] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0049] It should be noted that when an element is considered to be "connected" to another element, it may be directly connected to another element and combined with it as a whole, or there may be an intermediate element at the same time. The terms "disconnected", "one end", "the other end" and similar expressions used herein are for illustrative purposes only.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0051] When a ship is docked at a pier or other ship or offshore platform, using an external power source can save fuel and reduce carbon emissions, which is very environmentally friendly and economical. Therefore, the ship's shore power connection system is a very important facility on board, and is equipped on almost all ships. The ship obtains power from external power distribution devices such as the dock distribution box or the external power supply facilities of other ships (or offshore platforms), and usually connects the external power source to the ship's distribution system through the ship's shore power connection system.

[0052] The traditional ship shore power connection system generally consists of shore power cable, shore power cable winch (including slip ring), fixed laying cable, shore power box, etc. Take the ship with two shore power cables as an example. Figure 1 As shown, Figure 1 This is a schematic diagram of the structure of the traditional technology ship shore power connection system; when the ship requires a large external power capacity, it is usually necessary to configure two or more shore power cables, and use the cables in parallel to meet the maximum capacity demand of the ship's shore power operating conditions.

[0053] In the implementation process of traditional technology, when two or more shore power cables are used at the same time, it is easy to misconnect the line phase sequence, resulting in inconsistent phases of the current-carrying core wires in the cables used in parallel, which can lead to phase-to-phase short-circuit faults in the shore power lines and pose a hidden danger to electricity use.

[0054] In order to solve the problem that the shore power cable is easily connected in the wrong phase sequence and there are hidden dangers of power consumption in the traditional shore power connection system, the embodiment of the present invention provides a ship shore power connection circuit, see Figure 2 , Figure 2 It is a first schematic structural diagram of Embodiment 1 of the ship shore power connection circuit of the present invention; it includes a bus 210 whose output end is connected to the shore power box and each input circuit 220 connected to the corresponding shore power cable;

[0055] The input circuit 220 includes a switch module 222, a cable input terminal 224, and a phase difference detection module 226 connected to the switch module; the cable input terminal 224 is connected to the bus 210 through the switch module 222 and the phase difference detection module 226;

[0056] When the phase difference detection module 226 detects that there is a phase difference between the bus 210 and the cable input terminal 224 , the phase difference detection module 226 controls the switch module 222 to disconnect the cable input terminal 224 from the bus 210 .

[0057] Specifically, in the embodiment of the present invention, when the phase difference detection module 226 detects that the phase of the bus 210 connected to the shore power box is different from the phase of the input circuit 220 connected to the shore power cable, the switch module 222 is controlled to disconnect the cable input end 224 from the bus 210, thereby solving the problem of phase short circuit fault caused by the different phase sequences of the input circuits 220, which leads to the phase difference between the bus 210 and the cable input end 224; specifically, the phase difference detection module 226 detects the phase difference when the switch module 222 disconnects the cable input end 224 from the bus 210 and prevents current transmission, and maintains the switch module 222 disconnecting the cable input end 224 from the bus 210;

[0058] It should be noted that, in the embodiment of the present invention, at least two input circuits 220 are included, which can be connected to at least two shore power cables; the shore power cable is connected to the cable input end 224 of the input circuit 220, and transmits the current to the bus 210 through the cable input end 224; when multiple shore power cables are working at the same time, the phase sequence of the shore power cables is easily misconnected, which will cause different phases between the input circuits 220, thereby causing a phase difference between the bus 210 and the cable input end 224, and then causing a phase-to-phase short circuit fault;

[0059] The phase difference detection module 226 can be used to collect signal parameters such as phase and voltage at both ends, and detect whether there is a phase difference between the two ends. For example, when using domestic 380V three-phase electricity as an external power source, the phase difference caused by the wrong phase sequence of the cable can be 120°; and the phase difference detection module 226 is not used for current transmission between the cable input end 224 and the bus 210; when the phases at the two ends are inconsistent, the control switch module 222 is disconnected from the bus 210, thereby disconnecting the cable input end 224 from the bus 210, preventing the current transmission between the bus 210 and the cable input end 224, and avoiding the phase-to-phase short circuit fault caused by the phase difference between the bus 210 and the cable input end 224;

[0060] The switch module 222 can be used to control the on and off of the cable input end 224 and the bus 210. When the switch module 222 disconnects from the bus 210, there is no current transmission between the cable input end 224 and the bus 210; when a phase difference is detected, the switch module 222 controls the cable input end 224 to remain disconnected from the bus 210.

[0061] In the technical solution of the embodiment of the present invention, when the ship shore power connection circuit is connected to the external power supply through two shore power cables, the three current-carrying core wires of the shore power cable are directly connected in parallel at one end of the external power supply. For example, the three core wires of the shore power cable 1 are A, B, and C, and the three core wires of the shore power cable 2 are a, b, and c; at the external power distribution box, A and a are connected in parallel, B and b are connected in parallel, and C and c are connected in parallel; if at the other end, there is a phase sequence misconnection, A is not connected in parallel with a, but connected in parallel with b (or c), the phase difference will cause a phase-to-phase short circuit fault of the shore power line; based on the technical solution of the embodiment of the present invention, in the field of ship shore power connection, the phase difference detection module 226 can detect the existence of the phase difference to avoid the phase-to-phase short circuit fault, and there is no need to accurately measure the phase difference of the two cables at the cable input end through electronic circuits such as a single-chip microcomputer, thereby reducing the detection cost, eliminating the hidden dangers of power safety, and ensuring the safety of power use of ship shore power.

[0062] The interlocking design between the phase difference detection module 226 and the switch module 222 can avoid the line phase short circuit fault caused by the phase inconsistency between the current-carrying core wires in the shore power cable corresponding to the cable input terminal 224 connected to the external power distribution device in parallel, and can ensure that the shore power cable corresponding to the cable input terminal 224 can be put into use only when the connection is correct;

[0063] The embodiment of the present invention detects the phase difference between the bus 210 and the cable input end 224 through the phase difference detection module 226. When the phases of the bus 210 and the cable input end 224 are different, the control switch module 222 disconnects the cable input end 224 from the bus 210, thereby preventing the current transmission between the bus 210 and the cable input end 224. The problem of phase-to-phase short circuit fault when the shore power line is energized due to wrong connection during the connection of the ship's shore power cable is solved, thereby ensuring the safety of shore power use, especially when two or more shore power cables are used at the same time, it is easy to connect the phase sequence incorrectly, resulting in inconsistent phases of the current-carrying core wires in the cables used in parallel, causing the shore power cable phase-to-phase short circuit fault problem.

[0064] In order to specifically explain the implementation process of the technical solution of the embodiment of the present invention, an example is used for illustration.

[0065] In a specific example, Figure 3 , 4 As shown, Figure 3This is a primary circuit structure diagram of an example of a ship shore power connection circuit of the present invention. Figure 4 The first structural diagram of the control circuit of the ship shore power connection circuit example of the present invention; the cable input end includes input end ① and input end ②; the switch module includes circuit breakers QF1, QF2 and the corresponding undervoltage release coil MN of the circuit breaker; the phase difference detection module includes relays KA2, KA3, KA5, KA6; relays KA2 and KA3 are used to detect whether the phase of input end ① is consistent with that of the bus, and relays KA5 and KA6 are used to detect whether the phase of input end ② is consistent with that of the bus; the undervoltage release coil MN of circuit breakers QF1 and QF2 is used for undervoltage protection and prohibiting the closing of the circuit breaker when the phases of the two input ends are inconsistent, so as to ensure the safety of shore power use.

[0066] Furthermore, since the phase difference will generate a voltage difference, the phase difference detection method may include voltage difference detection.

[0067] In a specific embodiment, Figure 5 As shown, Figure 5 It is a second schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention, wherein the phase difference detection module is a voltage difference detection unit;

[0068] When the voltage difference detection unit detects that there is a voltage difference between the bus bar and the cable input end, the voltage difference detection unit controls the switch module to disconnect the cable input end from the bus bar.

[0069] Specifically, the phase difference detection module may be a voltage difference detection unit; the embodiment of the present invention detects the voltage difference between its two ends through the voltage difference detection unit, and when there is a voltage difference between the two ends, controls the switch module to disconnect the cable input end from the bus, thereby solving the problem that the phase sequence of each input circuit is different, resulting in a phase difference between the bus and the cable input end, and then causing a phase-to-phase short circuit fault; specifically, the voltage difference detection unit detects the voltage difference when the switch module disconnects the cable input end from the bus and prevents current transmission, and maintains the switch module disconnecting the cable input end from the bus;

[0070] It should be noted that when there is a phase difference between the cable input end and the bus, a voltage difference may occur between the two. For example, when domestic 380V three-phase electricity is used as an external power source, the voltage difference caused by the wrong phase sequence of the cable may be 380V. The voltage difference detection unit can be used to collect the voltage signal parameters at both ends and detect the voltage difference at both ends. When there is a voltage difference between the two ends, the control switch module disconnects the connection between the cable input end and the bus, preventing the current transmission between the bus and the cable input end, avoiding the phase-to-phase short circuit fault caused by the voltage difference between the bus and the cable input end, and ensuring the safety of shore power use.

[0071] Based on the technical solution of the embodiment of the present invention, in the field of ship shore power connection, the existence of the voltage difference can be detected by the voltage difference detection unit to avoid the phase-to-phase short circuit fault. There is no need to accurately measure the voltage difference between the two cables at the cable input end through electronic circuits such as a single-chip microcomputer, thereby reducing the detection cost, eliminating the hidden dangers of electricity safety, and ensuring the safety of ship shore power.

[0072] Preferably, the phase difference detection can be implemented by a relay.

[0073] In a specific embodiment, Figure 6 As shown, Figure 6 This is a third schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention; the first phase port of the cable input end is connected to the first phase circuit of the bus through the switch module, and the second phase port is connected to the second phase circuit of the bus through the switch module;

[0074] The phase difference detection module includes a first relay and a second relay;

[0075] One end of the coil of the first relay is connected to the first phase circuit of the bus, and the other end is connected to the first phase port of the cable input end; when there is a phase difference between the first phase circuit and the first phase port, the first relay controls the switch module to disconnect the cable input end from the bus;

[0076] One end of the coil of the second relay is connected to the second phase circuit of the bus, and the other end is connected to the second phase port of the cable input end; when there is a phase difference between the second phase circuit and the second phase port, the second relay controls the switch module to disconnect the cable input end from the bus.

[0077] Specifically, the embodiment of the present invention detects the phase difference between the cable input end and the bus through the first relay and the second relay; when there is a phase difference between the cable input end and the bus, it can cause a voltage difference between the two ends of the first relay and / or the two ends of the second relay, and the voltage difference can cause the first relay and / or the second relay to control the switch module to disconnect the cable input end from the bus, thereby solving the problem of phase-to-phase short circuit fault caused by different phase sequences of the input circuits, resulting in a phase difference between the bus and the cable input end.

[0078] It should be noted that, in the embodiments of the present invention, there are multiple ways for the relay to control the switch module; in a specific example, the normally closed contacts of the first relay and the second relay can both control the connection or disconnection of the switch module, and the phase difference can cause a voltage difference to be generated at both ends of the coil of the first relay and / or at both ends of the coil of the second relay, and the voltage difference can cause the normally closed contacts corresponding to the coil to be disconnected, thereby controlling the switch module to remain disconnected, preventing current transmission between the cable input end and the bus, avoiding phase-to-phase short circuit faults caused by the phase difference between the bus and the cable input end, and ensuring the safety of shore power use; based on the technical solution of the embodiments of the present invention, in the field of ship shore power connection, the existence of phase difference can be detected by a phase difference detection module to avoid the phase-to-phase short circuit fault, and there is no need to accurately measure the phase difference between the two cables at the cable input end through electronic circuits such as a single-chip microcomputer, thereby reducing detection costs, eliminating power safety hazards, and ensuring the safety of ship shore power use.

[0079] In a specific example, Figure 3 , 4 As shown, the first relay may include relays KA2 and KA5, and the second relay may include KA3 and KA6. Both ends of each relay are connected to the bus and the cable input end through a fuse.

[0080] The switch module can be used to control the on and off of the cable input end and the bus, and can be specifically composed of devices such as a circuit breaker and a control coil.

[0081] In a specific embodiment, Figure 7 As shown, Figure 7 This is a fourth schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention, wherein the switch module includes a circuit breaker and a pressure loss tripping coil connected to the phase difference detection module and the circuit breaker;

[0082] One end of the circuit breaker is connected to the busbar, and the other end is connected to the cable input end;

[0083] When the phase difference detection module detects a phase difference between the bus and the cable input end, it controls the undervoltage release coil to cut off the power and the circuit breaker to disconnect the cable input end from the bus.

[0084] Specifically, the switch module can be composed of a circuit breaker and a pressure-loss release coil; the two ends of the circuit breaker are respectively connected to the bus and the cable input; when the pressure-loss release coil is powered off, the circuit breaker can be controlled to be unable to close; when the phase of the bus is different from the phase of the cable input end, the phase difference detection module controls the pressure-loss release coil to power off, so that the circuit breaker disconnects the connection between the cable input end and the bus, prevents the current transmission between the bus and the cable input end, avoids the phase-to-phase short circuit fault caused by the voltage difference between the bus and the cable input end, and ensures the safety of shore power use.

[0085] It should be noted that the undervoltage release coil can be used for undervoltage protection; when the phases of the input circuits are inconsistent, the undervoltage release coil is controlled to be de-energized, so that the circuit breaker cannot be closed; further, after the external power supply (such as the shore power cable) is used and the external power distribution switch is disconnected, the circuit breaker will automatically trip due to the de-energization of the undervoltage release coil, ensuring that the circuit breaker is in the disconnected state before the next use of the external power supply, thereby ensuring the safety of shore power use;

[0086] In a specific example, Figure 3 , 4 As shown, the switch module may include circuit breakers QF1, QF2 and corresponding undervoltage tripping coils MN; the undervoltage tripping coils MN of the circuit breakers QF1 and QF2 are used for undervoltage protection and for prohibiting the circuit breaker closing when the phases of the two input terminals are inconsistent.

[0087] Under certain working conditions, the external power capacity required by ships is relatively small, and ships often only use part of the shore power cables. However, due to the lack of measures to isolate the unused cable input ends and the corresponding shore power cables from the live lines in use, the unused cable input ends and the corresponding shore power cables are also live, which can easily cause electric shock accidents and pose a safety hazard;

[0088] To this end, in a specific embodiment, see Figure 8 , Figure 8 for Figure 8 This is a fifth schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention, wherein the input circuit further includes a power detection module connected to a cable input end, a switch module, and a phase difference detection module;

[0089] When the power detection module detects that the cable input end is powered off, it disconnects the switch module, the phase difference detection module and the bus.

[0090] Specifically, when the cable input end is powered off, the power detection module controls the switch module and the phase difference detection module to disconnect from the bus bar, so as to prevent the current of the bus bar from being transmitted to the unused cable input end when the cable input end is powered off;

[0091] It should be noted that the connection and disconnection of the switch module can isolate the unused cable input end from the live cable input end in use to avoid electric shock accidents; the detection results of the phase difference detection module and the power detection module are interlocked with the switch module, so that the switch module can only be connected when the cable input end and the shore power cable are correctly connected and powered, ensuring the safety of shore power use;

[0092] In a specific example, Figure 3 , 4As shown, the power detection module may include relays KA1 and KA4; relays KA1 and KA4 are respectively used to detect whether input terminals ① and ② of the ship's shore power connection circuit are energized; when the relay input terminal is not energized, the connection between the switch module and the phase difference detection module and the bus can be disconnected through the normally open contact.

[0093] Specifically, the power detection module can be implemented by devices such as relays;

[0094] In a specific embodiment, Fig. 9 As shown, Fig. 9 It is a sixth schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention, wherein the power detection module includes a third relay;

[0095] One end of the coil of the third relay is connected to the first phase port of the cable input end, and the other end is connected to the second phase port of the cable input end; the switch module and the phase difference detection module are connected to the bus through the normally open contact of the third relay;

[0096] When the third relay detects that the cable input end is powered off, the normally open contact of the third relay is controlled to disconnect the switch module, the phase difference detection module and the bus.

[0097] Specifically, the coil of the third relay controls the connection and disconnection of the switch module, the phase difference detection module and the bus by detecting the power on and off of the cable input end; when the cable input end is powered off, the switch module and the phase difference detection module are controlled to disconnect from the bus to prevent the current of the bus from being transmitted to the unused cable input end when the cable input end is powered off;

[0098] In a specific example, Figure 3 , 4 As shown, the third relay may include relays KA1 and KA4, and the cable input end may include input end ① and input end ②; relays KA1 and KA4 are respectively used to detect whether input end ① and input end ② of the ship shore power connection circuit are energized; when the relay input end is not energized, the connection between the switch module and the phase difference detection module and the bus can be disconnected through the normally open contact.

[0099] In a specific embodiment, Fig.10 As shown, Fig.10 The seventh schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention, wherein the input circuit comprises a first input circuit connected to a first shore power cable and a second input circuit connected to a second shore power cable;

[0100] The first input circuit includes a first power supply control module connected to a cable input terminal of the first input circuit, a switch module, and a phase difference detection module;

[0101] The second input circuit includes a second power supply control module connected to a cable input end of the second input circuit, a switch module, and a phase difference detection module;

[0102] The first power control module is connected to the second power control module;

[0103] When the cable input end of the first input circuit is powered on, the first power control module controls the switch module and the phase difference detection module of the first input circuit to connect to the bus, and controls the second power control module to disconnect from the cable input end, the switch module and the phase difference detection module of the second input circuit.

[0104] Specifically, the input circuit can be divided into a first input circuit and a second input circuit; the first input circuit also includes a first power control module, and the second input circuit also includes a second power control module; the first power control module and the second power control module can be used to control the connection or disconnection of the switch module, the phase difference detection module and the bus bar of the input circuit, and the first power control module and the second power control module control each other;

[0105] Specifically, when the cable input end of the first input circuit is powered on, the first power control module can control the switch module and the phase difference detection module of the first input circuit to connect to the bus, and control the second power control module to disconnect the cable input end, the switch module, and the phase difference detection module of the second input circuit, so that the switch module and the phase difference detection module of the second input circuit can be connected only when the cable input end thereof is correctly connected to the shore power cable and powered on, and are not affected by the control of the second power control module, thereby ensuring the power safety of the shore power connection;

[0106] In a specific example, Figure 3 , 4 As shown, the first power control module may include a contactor KM1, and the second power control module may include a contactor KM2; the contactors KM1 and KM2 may be used to select the power supply of the control circuit, that is, to control the power supply of the transformer TC; when only one shore power cable is used, only one input end has power, and through the action of one of the contactors KM1 (acting when the input end ① has power) and KM2 (acting when the input end ② has power), the power supply at the end with power is selected as the control power supply; when two or more shore power cables are used, due to the action of the delay relay KT, the contactor KM1 acts and KM2 does not act, and the input end ① is selected as the power supply of the control circuit.

[0107] In a specific embodiment, when the cable input end of the first input circuit is powered off and the cable input end of the second input circuit is powered on, the second power supply control module controls the switch module and the phase difference detection module of the second input circuit to connect to the bus, and controls the first power supply control module to disconnect from the cable input end, the switch module, and the phase difference detection module of the first input circuit.

[0108] Specifically, when the cable input end of the first input circuit is powered off and the cable input end of the second input circuit is powered on, the second power supply control module can control the switch module and the phase difference detection module of the second input circuit to connect to the bus, and control the first power supply control module to disconnect from the cable input end, the switch module and the phase difference detection module of the first input circuit, so that the switch module and the phase difference detection module of the first input circuit can only be connected when their cable input ends are correctly connected to the shore power cable and powered on, and are not affected by the control of the first power supply control module, thereby ensuring the safety of shore power use.

[0109] In a specific embodiment, see Fig.11 , Fig.11 The eighth schematic structural diagram of an embodiment of a ship shore power connection circuit of the present invention, wherein the second input circuit further comprises a time delay relay connected to a cable input end of the second input circuit;

[0110] The second power supply control module is connected to the cable input end of the second input circuit through the normally open contact of the time delay relay;

[0111] When the cable input end of the first input circuit and the cable input end of the second input circuit are both powered on, the first power supply control module controls the switch module and the phase difference detection module of the second input circuit to connect to the bus, and controls the second power supply control module to disconnect the second power supply control module from the cable input end of the second input circuit through the time delay relay.

[0112] Specifically, the second power supply control module is connected to the cable input end of the second input circuit through the normally open contact of the time delay relay; when the first input circuit and the second input circuit are both powered on, due to the effect of the time delay relay, the first power supply control module is turned on before the second power supply control module, and the switch module and the phase difference detection module of the first input circuit can be controlled to connect to the bus, and the second power supply control module can be controlled to disconnect from the cable input end, the switch module and the phase difference detection module of the second input circuit, so that the switch module and the phase difference detection module of the second input circuit can only be connected when the cable input end thereof is correctly connected to the shore power cable and powered on, and is not affected by the control of the second power supply control module, thereby ensuring the safety of shore power use;

[0113] In a specific example, Figure 3 , 4As shown, it also includes a delay relay KT, the first power control module may include a contactor KM1, and the second power control module may include a contactor KM2; the contactors KM1 and KM2 can be used to control the power selection of the circuit, that is, to control the power supply of the transformer TC; when two cables need to be used at the same time to meet the use requirements, due to the action of the delay relay KT, the coil of the contactor KM1 is energized first, the normally closed contact of the contactor KM1 is instantly disconnected so that the coil of the contactor KM2 is not energized, the main contact of the contactor KM1 is closed, and the power supply of the control circuit automatically selects the power supply from the input terminal ①.

[0114] To facilitate understanding of the specific implementation process of the ship shore power connection circuit according to the embodiment of the present invention, the following is a Figure 3 , 4 , 12 as an example to illustrate, Fig.12 This is a second structural diagram of the control circuit of an example of a ship shore power connection circuit of the present invention.

[0115] In a specific example, the cable input end includes input end ① and input end ②; the switch module includes circuit breakers QF1, QF2 and a pressure loss tripping coil MN corresponding to the circuit breaker;

[0116] The power supply detection module includes relays KA1, KA4, and KA7, which are used to detect whether the input terminal ①, input terminal ②, and output terminal of the ship's shore power connection circuit are energized;

[0117] The phase difference detection module includes relays KA2, KA3, KA5, and KA6. When shore power cables ① and ② are used at the same time, relays KA2 and KA3 are used to detect whether the phases of input terminal ① are consistent with those of the busbar, and relays KA5 and KA6 are used to detect whether the phases of input terminal ② are consistent with those of the busbar.

[0118] The power control module includes contactors KM1 and KM2; the power control module and time relay KT are used to control the power selection of the circuit;

[0119] The selector switch SA is used to select which circuit breaker to close (circuit breaker QF1 or QF2) to avoid closing both circuit breakers at the same time; relays KA9 and KA10 are used to lock the selector switch SA contacts connected in series in the control circuit of the pressure-loss coil MN of the circuit breaker that closes first, so as to avoid affecting the closing state of the circuit breaker that closes first when the selector switch SA handle is turned to other positions;

[0120] The undervoltage tripping coil MN of the circuit breakers QF1 and QF2 is used for undervoltage protection and for prohibiting the closing of the circuit breaker when the phases of the two input terminals are inconsistent;

[0121] There are also test light button PB, indicator lights HL1~HL9, buzzer MY, and fuses FU1~FU16. The test light button PB is used to test the indicator lights HL1~HL9 and buzzer MY on the control box; the indicator lights HL1~HL4 are used to indicate the opening or closing state of the circuit breakers QF1 and QF2, the indicator lights HL5~HL7 are used to indicate whether the input and output terminals are energized, the indicator lights HL8~HL9 are used for light alarm when the phases of the two input terminals are consistent, and the phases of which are inconsistent can be judged based on these two indicator lights, and the buzzer MY is used for sound alarm when the phases of the two input terminals are consistent; fuses FU1~FU16 can be used to protect the circuit.

[0122] When only one cable is needed to meet the use requirements, take the case where input terminal ① is connected to an external power distribution device and input terminal ② is not connected to a power source. After the switch in the external power distribution device is closed, the external power source reaches input terminal ① through the shore power cable. The coil of contactor KM1 is energized, the main contacts of contactor KM1 are closed, and the control circuit automatically selects the power source from input terminal ①. At the same time, relay KA1 is energized, and the normally open contacts of relay KA1 are closed. At this time, the busbar is not energized, the coils of relays KA2 and KA3 are not energized, and the normally closed contacts of relays KA2 and KA3 are in a closed state. The handle of the selector switch SA is turned to the "QF1" position, and contacts 1-2 of the selector switch SA are connected. The undervoltage release coil MN of the circuit breaker QF1 is energized, and the circuit breaker QF1 is closed, and the busbar is energized.

[0123] At this time, the busbar is in phase with the input terminal ①, the voltage difference between the two ends of the relay KA2 and KA3 coils is 0V, the normally closed contacts of the relays KA2 and KA3 remain closed, the circuit breaker QF1 remains closed, and the busbar outputs power to the shore power box through the output terminal. Because there is no power input at the input terminal ②, the relay KA4 coil is not energized, the normally open contact of the relay KA4 is in the open state, and the circuit breaker QF2 cannot be closed because the pressure loss tripping coil MN is not energized. The normally open contact of the relay KA4 connected in series with the relay KA5 and KA6 coils is also in the open position, ensuring that the shore power cable ② is isolated from the live circuit.

[0124] After using the external power supply, disconnect the switch in the external power distribution device, and the circuit breaker QF1 will automatically trip due to the loss of power to the undervoltage trip coil MN, ensuring that the circuit breaker QF1 is in the disconnected state before the next use of the external power supply.

[0125] When two cables are required to be used at the same time to meet the use requirements, both input terminals ① and ② are connected to the external power distribution device. After the switch in the external power distribution device is closed, the external power reaches input terminal ① through shore power cable ① and reaches input terminal ② through shore power cable ②. Due to the action of the delay relay KT, the coil of contactor KM1 is energized first, the normally closed contact of contactor KM1 is instantly disconnected, so that the coil of contactor KM2 is not energized, the main contact of contactor KM1 is closed, and the control circuit automatically selects the power from input terminal ①.

[0126] Since both input terminals ① and ② are energized, the coils of relays KA1 and KA4 are energized, and the normally open contacts of relays KA1 and KA4 are closed. At this time, the busbar is not energized, and the coils of relays KA2, KA3, KA5 and KA6 are not energized. The normally closed contacts of relays KA2, KA3, KA5 and KA6 are closed. Move the handle of the selector switch SA to the "QF1" position (to close the circuit breaker QF1 first, or you can close the circuit breaker QF2 first, whichever is better). Take circuit breaker QF1 as an example. If circuit breaker QF2 is closed first, the handle of the selector switch SA needs to be turned to the "QF2" position), the contacts 1-2 of the selector switch SA are connected, the undervoltage release coil MN of the circuit breaker QF1 is energized, the circuit breaker QF1 is closed, the bus is energized, the bus is in phase with the input terminal ①, the voltage difference between the two ends of the coils of relays KA2 and KA3 is 0V, the normally closed contacts of relays KA2 and KA3 remain in the closed state, and the circuit breaker QF1 remains in the closed state. The coil of relay KA9 is energized, and its normally open contacts are closed, so that the contacts 1-2 of the selector switch SA are locked, so that when the handle of the selector switch SA is turned to other positions, it does not affect the state of the closed circuit breaker QF1.

[0127] If the phases of input terminals ① and ② are consistent, the voltage difference between the two ends of the coils of relays KA5 and KA6 is 0V, and the normally closed contacts of relays KA5 and KA6 are in a closed state. Move the handle of the selector switch SA to the "QF2" position, and the contacts 3-4 of the selector switch SA are connected, and the undervoltage release coil MN of the circuit breaker QF2 is energized. At this time, the circuit breaker QF2 is closed, and the two cables are powered at the same time. The coil of relay KA10 is energized, and its normally open contacts are closed, so that the contacts 3-4 of the selector switch SA are locked, so that when the handle of the selector switch SA is moved to other positions, it will not affect the state of the closed circuit breaker QF2.

[0128] If the phases of input terminal ① and input terminal ② are inconsistent, at least one of the voltage differences across the coils of relays KA5 and KA6 is not 0V. At this time, at least one of the normally closed contacts of relays KA5 and KA6 is in the disconnected state, and the undervoltage release coil MN of circuit breaker QF2 is not energized, and circuit breaker QF2 cannot be closed, thus avoiding the short-circuit fault caused by the phase inconsistency between input terminal ① and input terminal ②. At this time, it is necessary to adjust the input end of the ship's shore power connection circuit or the wiring of the cable at the external power distribution device according to the alarm indicator light indicating "phase inconsistency" on the control circuit, so that the two input lines can be closed when the phases are consistent.

[0129] After using the external power supply, disconnect the switch in the external power distribution device. Circuit breakers QF1 and QF2 will automatically trip due to the loss of power to the undervoltage trip coil MN, ensuring that circuit breakers QF1 and QF2 are in the disconnected state before the next use of the external power supply.

[0130] On the other hand, based on the above-mentioned embodiments of the ship shore power connection circuit, the embodiment of the present invention further provides an isolating switch box using the above-mentioned embodiments of the ship shore power connection circuit, such as Fig.13 As shown, Fig.13 This is a first schematic structural diagram of an isolating switch box embodiment 1 of the present invention. The isolating switch box may include the above-mentioned ship shore power connection circuit.

[0131] It should be noted that the above-mentioned isolating switch box can realize the functions and effects of the above-mentioned ship shore power connection circuit, which will not be repeated here;

[0132] In a specific example, Fig.13 As shown, the shore power cable ① is connected to the input end ① of the isolating switch box through the shore power cable winch slip ring ① and the fixed laying cable ③, the shore power cable ② is connected to the input end ② of the isolating switch box through the shore power cable winch slip ring ② and the fixed laying cable ④, and the two ends of the fixed laying cables ⑤ and ⑥ are respectively connected in parallel to the output end of the isolating switch box and the input end of the shore power box.

[0133] Among them, shore power cables ① and ② and fixed cables ③ and ④ use cables with grounding cores, and the grounding wires are grounded at the isolation switch box. Fixed cables ⑤ and ⑥ use cables without grounding cores; the shore power box has overload, short circuit, undervoltage protection, phase sequence monitoring, phase sequence conversion and other functions.

[0134] When a ship equipped with two or more shore power cables uses a traditional shore power connection system, it is easy to misconnect the cable line, causing a phase-to-phase short circuit fault of the shore power cable. In addition, the unused shore power cables are not isolated from the shore power cables in use, which can easily cause electric shock accidents and pose a hidden danger to electricity use.

[0135] To this end, one of the above technical solutions has the following advantages and beneficial effects: the ship shore power connection circuit and the isolating switch box of the present invention, when the phase difference detection module detects that there is a phase difference between the bus connected to the shore power box and the input circuit connected to the shore power cable, controls the switch module to disconnect the cable from the bus; solves the problem of phase-to-phase short circuit fault when the shore power line is energized due to wrong connection during the ship shore power cable connection process, and ensures the safety of shore power use;

[0136] The interlocking design between the phase difference detection module and the switch module can ensure that the shore power cable can be put into use only if it is correctly wired; the interlocking design between the power detection module and the switch module can isolate the unused cable input end from the energized cable input end to avoid electric shock accidents; by adopting the technical solution of the embodiment of the present invention, only a low-cost ship shore power connection circuit and / or isolation switch box needs to be added to eliminate the safety hazards of the existing shore power connection system, ensure the safety of shore power use, and protect the safety of equipment and lives on board.

[0137] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0138] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A ship shore power connection circuit, characterized in that: It includes a busbar connected to the shore power box at the output end and input circuits connected to the corresponding shore power cables; The input circuit includes a switch module, a cable input end, and a phase difference detection module connected to the switch module; the cable input end is connected to the bus through the switch module and the phase difference detection module respectively; When the phase difference detection module detects that there is a phase difference between the bus and the cable input end, the phase difference detection module controls the switch module to disconnect the cable input end from the bus; The first phase port of the cable input end is connected to the first phase circuit of the bus through the switch module, and the second phase port is connected to the second phase circuit of the bus through the switch module; The phase difference detection module includes a first relay and a second relay; One end of the coil of the first relay is connected to the first phase circuit of the bus, and the other end is connected to the first phase port of the cable input end; when there is a phase difference between the first phase circuit and the first phase port, the first relay controls the switch module to disconnect the cable input end from the bus; One end of the coil of the second relay is connected to the second phase circuit of the busbar, and the other end is connected to the second phase port of the cable input end; The second relay controls the switch module to disconnect the cable input end from the bus when there is a phase difference between the second phase circuit and the second phase port; The switch module includes a circuit breaker and a pressure loss tripping coil connected to the phase difference detection module and the circuit breaker; One end of the circuit breaker is connected to the bus bar, and the other end is connected to the cable input end; When the phase difference detection module detects that there is a phase difference between the bus and the cable input end, it controls the undervoltage tripping coil to be powered off and the circuit breaker to disconnect the cable input end from the bus.

2. The ship shore power connection circuit according to claim 1, characterized in that: The phase difference detection module is a voltage difference detection unit; When the voltage difference detection unit detects that there is a voltage difference between the bus and the cable input end, the voltage difference detection unit controls the switch module to disconnect the cable input end from the bus.

3. The ship shore power connection circuit according to claim 1, characterized in that: The input circuit also includes a power detection module connected to the cable input end, the switch module, and the phase difference detection module; When the power supply detection module detects that the cable input end is powered off, the power supply detection module disconnects the switch module, the phase difference detection module and the bus.

4. The ship shore power connection circuit according to claim 3, characterized in that: The power detection module includes a third relay; One end of the coil of the third relay is connected to the first phase port of the cable input end, and the other end is connected to the second phase port of the cable input end; the switch module and the phase difference detection module are connected to the busbar through the normally open contact of the third relay; When the third relay detects that the cable input end is powered off, the third relay controls the normally open contact of the third relay to disconnect the switch module, the phase difference detection module and the bus.

5. The ship shore power connection circuit according to any one of claims 1 to 4, characterized in that: The input circuit includes a first input circuit connected to a first shore power cable and a second input circuit connected to a second shore power cable; The first input circuit includes a first power supply control module connected to a cable input terminal of the first input circuit, a switch module, and a phase difference detection module; The second input circuit includes a second power supply control module connected to a cable input terminal of the second input circuit, a switch module, and a phase difference detection module; The first power control module is connected to the second power control module; When the cable input end of the first input circuit is powered on, the first power control module controls the switch module and the phase difference detection module of the first input circuit to connect to the bus, and controls the second power control module to disconnect from the cable input end, the switch module, and the phase difference detection module of the second input circuit.

6. The ship shore power connection circuit according to claim 5, characterized in that: When the cable input end of the first input circuit is powered off and the cable input end of the second input circuit is powered on, the second power supply control module controls the switch module and the phase difference detection module of the second input circuit to connect to the bus, and controls the first power supply control module to disconnect from the cable input end, the switch module, and the phase difference detection module of the first input circuit.

7. The ship shore power connection circuit according to claim 5, characterized in that: The second input circuit further comprises a time delay relay connected to the cable input end of the second input circuit; The second power supply control module is connected to the cable input end of the second input circuit through the normally open contact of the time delay relay; When the cable input end of the first input circuit and the cable input end of the second input circuit are powered on, the first power supply control module controls the switch module and the phase difference detection module of the second input circuit to connect to the bus, and controls the second power supply control module to disconnect the second power supply control module from the cable input end of the second input circuit through the time delay relay.

8. An isolating switch box, characterized in that: The isolating switch box comprises the ship shore power connection circuit according to any one of claims 1 to 7.

Images