Input power supply switching circuit and railway communication power supply system

Abstract

The invention discloses an input power supply switching circuit and a railway communication power supply system. The input power supply switching circuit comprises an alternating current switching device, circuit breakers QF1-QF4 and change-over switches SA1-SA2. The input ends of the QF1 and the QF2 are correspondingly connected with two paths of alternating current input power supplies; the output ends of the QF1 and the QF2 are connected with the QF3 through an alternating current switching device; the alternating current switching device is used for switching two paths of alternating current input power supplies into one path of alternating current power supply and then accessing the QF3; the output end of the QF3 is connected with post-stage electric equipment; the input end of the QF4 is connected with the output end of a generator F power supply; and the output end of the QF4 is connected with the power supply input end of post-stage electric equipment. Two paths of input power supplies and one path of generator power supply can be connected, when one path fails, the input power supplies are reliably switched or both paths of input power supplies fail, power is supplied by the generator, normal power supply to railway communication equipment is guaranteed, and train operation safety is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of input power switching and railway transportation, and in particular to an input power switching circuit and a railway communication power supply system. Background Art

[0002] Rail transit is an important form of transportation. To ensure the orderly operation of rail transit, power supply equipment for rail transit communication equipment is particularly important. Among them, railway communication power supply system equipment is used to provide power for railway station communication equipment.

[0003] The railway communication power supply system is a key basic equipment for railway signal driving and dispatching communication equipment, which can ensure the reliable, accurate and safe operation of communication equipment. Different communication equipment has different power consumption, but has high requirements for power supply quality and reliability. Therefore, relevant departments have formulated relevant standards for railway communication power supply systems. In the new standards, special requirements are made for input switching circuits.

[0004] Railway communication equipment is a DC48V power-consuming device, which mainly uses multiple rectifier modules working in parallel to rectify the AC power supply into DC48V for power supply. The railway communication power supply system is a power supply system equipment that integrates AC input, rectification, DC output and monitoring units in one cabinet.

[0005] However, the AC input of the current railway communication power supply system can usually only be connected to one power supply. When the input power supply has over-voltage, under-voltage, power failure, phase loss and other faults, it will affect the normal operation of the railway communication equipment. In severe cases, it may even cause all railway communication equipment to lose power instantly, causing unpredictable situations such as the possible stop of the running train, seriously affecting the safety of train operation.

[0006] Therefore, there is an urgent need to develop a technology that can solve the above technical problems. Summary of the invention

[0007] The purpose of the present invention is to provide an input power switching circuit and a railway communication power supply system in view of the technical defects in the prior art.

[0008] To this end, the present invention provides an input power switching circuit, which includes: an AC switching device, circuit breakers QF1-QF4 and transfer switches SA1-SA2;

[0009] The input terminals of the circuit breakers QF1 and QF2 are connected to two AC input power supplies accordingly;

[0010] Two AC input power supplies, including I mains input power supply and II mains input power supply;

[0011] The output terminals of the circuit breakers QF1 and QF2 are connected to the circuit breaker QF3 through the AC switching device;

[0012] The AC switching device is used to switch two AC input power sources into one AC power source and then connect it to the circuit breaker QF3;

[0013] The output terminal of the circuit breaker QF3 is connected to the power supply input terminal of the subsequent electrical equipment;

[0014] The input terminal of the circuit breaker QF4 is connected to the output terminal of the power supply of the generator F;

[0015] The output terminal of the circuit breaker QF4 is connected to the power supply input terminal of the subsequent electrical equipment.

[0016] In addition, the present invention provides a railway communication power supply system, which includes the input power switching circuit as described above, and a plurality of railway communication devices;

[0017] Railway communication equipment, connected to the input power switching circuit;

[0018] Railway communication equipment is the subsequent power-consuming equipment in the input power switching circuit.

[0019] It can be seen from the technical solution provided by the present invention that, compared with the prior art, the present invention provides an input power switching circuit and a railway communication power supply system, which are scientifically designed and can be connected to two input power supplies. When one of the input power supplies fails, the input power supply can be switched conveniently and reliably to ensure the normal power supply to the railway communication equipment, thereby ensuring the safe operation of the train, which has great practical significance.

[0020] In addition, the present invention can connect the generator power supply without disconnecting the mains input circuit breaker, thereby ensuring the continuity of the AC input power supply, thereby ensuring the normal operation of the railway communication equipment and the railway communication system, and ensuring the safe operation of the train. At the same time, the present invention can remotely switch between the two mains inputs when necessary.

[0021] In addition, the present invention provides an AC input switching circuit for a railway communication power supply system through a circuit layout of two AC input power supplies and one generator power supply. When both mains fail, the generator power supply is quickly connected to quickly complete emergency repair without affecting the subsequent railway communication equipment. After the mains is restored, the input power supply can also be restored without affecting the subsequent railway communication equipment, ensuring that the railway communication power equipment does not lose power.

[0022] In addition, by applying the present invention, remote switching can be performed when the city power needs to be repaired, avoiding the need for unmanned stations to dispatch personnel to the site for switching, which can effectively reduce the labor and time costs when switching unmanned communication stations.

[0023] After inspection, the circuit provided by the present invention is an AC input switching circuit with strong anti-interference ability and high safety. The manual rotary switch used is a safety switch and can be reliably applied to railway communication power supply system equipment. The circuit of the present invention can be made modular, which is convenient for access to the system and provides convenience for device maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of an input power switching circuit provided by the present invention;

[0025] Figure 2 A schematic diagram of a related acquisition control loop of a monitoring module including four monitoring units in an input power switching circuit provided by the present invention;

[0026] Figure 3 An electrical circuit diagram of an AC switching device in an input power switching circuit provided by the present invention;

[0027] Figure 4 A schematic diagram of the appearance of a switch SA1 used as a manual switch in an input power switching circuit provided by the present invention;

[0028] Figure 5 A schematic diagram of the appearance of a switch SA2 serving as a working mode switch in an input switching circuit provided by the present invention;

[0029] Figure 6 An electrical circuit diagram of a relay in an input power switching circuit provided by the present invention. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In the description of this patent, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "set" should be understood in a broad sense, for example, it can be fixedly connected or set, or it can be detachably connected or set, or connected or set in one piece. For ordinary technicians in this field, the specific meanings of the above terms in this patent can be understood according to specific circumstances.

[0032] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0033] See also Figures 1 to 5 , the present invention provides an input power switching circuit, comprising: an AC switching device, circuit breakers QF1-QF4 and transfer switches SA1-SA2;

[0034] The input terminals of the circuit breakers QF1 and QF2 are connected to two AC input power supplies (i.e., mains input power supplies, i.e., AC mains) accordingly;

[0035] Two AC input power supplies, including I mains input power supply and II mains input power supply;

[0036] The output terminals of the circuit breakers QF1 and QF2 are connected to the circuit breaker QF3 through the AC switching device;

[0037] The AC switching device is used to switch two AC input power sources into one AC power source and then connect it to the circuit breaker QF3;

[0038] The output end of the circuit breaker QF3 is connected to the power supply input end of the subsequent power-consuming equipment (such as railway communication equipment);

[0039] The input terminal of the circuit breaker QF4 is connected to the output terminal of the power supply of the generator F;

[0040] The output end of the circuit breaker QF4 is connected to the power supply input end of the subsequent power-consuming equipment (such as railway communication equipment).

[0041] In the present invention, in a specific implementation, the circuit breakers QF3 and QF4 are connected via a mechanical interlocking device.

[0042] It should be noted that the circuit breakers QF3 and QF4 select one path (i.e. one path of mains power or generator F power supply) to supply power to the subsequent electrical equipment (e.g. railway communication equipment) through a mechanical interlocking device. The mechanical interlocking device can be a mechanical component designed and produced by Tianjin Railway Signal Co., Ltd. for selecting one of two miniature circuit breakers, which is a component with mature technology. The mechanical interlocking device is a well-known technical means with mature technology in the prior art, and its installation method is the existing conventional method, which will not be repeated here.

[0043] It should be noted that the two AC input power supplies are two mains power supplies, which can be three-phase AC380V power supplies or single-phase AC220V power supplies. When it is a single-phase power supply, the live wire should be connected to the first pin of the circuit breaker QF1 or QF2.

[0044] In the present invention, in a specific implementation, the 1st, 3rd and 5th pins (i.e. contacts) of the input end of the circuit breaker QF1 are respectively connected to the A, B and C phase power lines of the I-way mains input power supply;

[0045] The 1st, 3rd and 5th pins of the input end of the circuit breaker QF2 are respectively connected to the A, B and C phase power lines of the II-way AC input power supply.

[0046] It should be noted that the input terminals of the circuit breakers QF1, QF2, QF3 and QF4 refer to the 1st, 3rd and 5th pins of the circuit breakers, and the output terminals refer to the 2nd, 4th and 6th pins of the circuit breakers.

[0047] In the present invention, in a specific implementation, the AC switching device includes a contactor 1KM~2KM;

[0048] The output terminals of the circuit breakers QF1 and QF2 are respectively connected to the contactors 1KM and 2KM in the AC switching device;

[0049] In specific implementation, the 2nd, 4th and 6th pins of the output terminal of the circuit breaker QFI pass through the AC transformers 1JC, 2JC and 3JC respectively, and are connected to the 1L1, 3L2 and 5L3 pins of the 1KM contactor in the AC switching device.

[0050] The 2nd, 4th and 6th pins of the output terminal of the circuit breaker QF2 are connected to the 1L1, 3L2 and 5L3 pins of the 2KM contactor in the AC switching device after passing through the AC transformers 4JC, 5JC and 6JC respectively;

[0051] It should be noted that the output ends of the AC transformers 1JC, 2JC, 3JC, 4JC, 5JC and 6JC refer to the 1st and 2nd pins of the AC transformers.

[0052] In the present invention, in a specific implementation, the output terminals of the contactors 1KM and 2KM in the AC switching device are connected to the input terminal of the circuit breaker QF3 after merging;

[0053] In a specific implementation, the output terminals 2T1, 4T2, and 6T3 of the contactor 1KM in the flow switching device are respectively connected to the corresponding output terminals 2T1, 4T2, and 6T3 of the contactor 2KM, and then connected to the input terminals 1, 3, and 5 of the circuit breaker QF3;

[0054] It should be noted that the input end of the AC switching device is the 1L1, 3L2 and 5L3 pins of the contactors 1KM and 2KM, and the output end of the AC switching device is the 2T1, 4T2 and 6T3 pins of the contactors 1KM and 2KM.

[0055] In the present invention, in a specific implementation, the 1st, 3rd, and 5th pins (i.e., contacts) of the input end of the circuit breaker QF4 are connected to the A, B, and C phase power lines of the power supply of the generator F;

[0056] Pins 2, 4 and 6 of the output terminal of circuit breaker QF4 are respectively converged and intersected with pins 2, 4 and 6 of the output terminal of circuit breaker QF3, and then connected to the subsequent electrical equipment (such as railway communication equipment) to supply power to the subsequent electrical equipment (such as railway communication equipment) (specifically, the A, B and C phase power access lines of the subsequent electrical equipment).

[0057] In the present invention, for specific implementation, see Figure 1 , Figure 3 As shown, for the AC switching device, the 62nd pin (i.e., the contact point) of the contactor 2KM is connected to the 1L1 pin of the contactor 1KM;

[0058] Pin 61 of contactor 2KM is connected to coil contact A2 of contactor 1KM;

[0059] The coil contact A1 of the contactor 1KM is connected to the 13th pin of the change-over switch SA1 and the 10th pin of the relay 1KA respectively;

[0060] The 14th pin of the transfer switch SA1 is connected to the 11th pin of the transfer switch SA2;

[0061] The second pin of the relay KA is connected to the 23rd pin of the transfer switch SA2;

[0062] The 24th pin of the transfer switch SA2 is connected to the 9th pin of the relay KA;

[0063] The first pin of the relay KA is connected to the 12th pin of the change-over switch SA2.

[0064] In a specific implementation, the 12th pin of the conversion switch SA2 is connected to the N-phase line (neutral line, such as the N-phase copper busbar) of any one of the two AC input power sources;

[0065] In the present invention, the specific implementation is as follows: Figure 1 , Figure 3 As shown, for the AC switching device, the 62nd pin of the contactor 1KM is connected to the 1L1 pin of the contactor 2KM;

[0066] Pin 61 of contactor 1KM is connected to coil contact A2 of contactor 2KM;

[0067] The coil contact A1 of the contactor 2KM is connected to the 23rd pin of the change-over switch SA1 and the 12th pin of the relay KA respectively;

[0068] The 24th pin of the transfer switch SA1 is connected to the 31st pin of the transfer switch SA2;

[0069] The 8th pin of the relay KA is connected to the 43rd pin of the transfer switch SA2;

[0070] The 44th pin of the transfer switch SA2 is connected to the 11th pin of the relay KA;

[0071] The 7th pin of the relay KA is connected to the 32nd pin of the transfer switch SA2.

[0072] In a specific implementation, the 32nd pin of the conversion switch SA2 is connected to the N-phase line (neutral line, such as the N-phase copper busbar) of any one of the two AC input power sources;

[0073] In the present invention, the specific implementation is as follows: Figure 4 The transfer switch SA1 is a manual switching switch. When the handle of the transfer switch SA1 is at the left 45° position, the manual control circuit of the mains I (i.e., the I-way mains input power supply) of the railway communication power supply system is in the on state, and the manual control circuit of the mains II (i.e., the II-way mains input power supply) is in the off state; when the handle of the transfer switch SA1 is at the right 45° position, the manual control circuit of the mains I of the railway communication power supply system is in the off state, and the manual control circuit of the mains II is in the on state; when the handle of the transfer switch SA1 is at the 0° position, the manual control circuits of the mains I and the mains II of the railway communication power supply system are both in the off state.

[0074] In specific implementation, the transfer switch SA1 is an existing transfer switch, and specifically, the transfer switch model LA39-A3-20CXS / K produced by Suzhou Siemens Electric Co., Ltd. can be used. The transfer switch can be customized according to circuit requirements, and the appearance of the transfer switch can be as follows Figure 4 As shown, the on-state of the conversion switch is shown in Table 1 below.

[0075] Table 1:

[0076]

[0077] In Table 1, X indicates on. Normal position 1 is the left 45° position, position 2 is the 0° position, and position 3 is the right 45° position;

[0078] Left 45° position (i.e. AC power I position): At this time, pins 13 and 14 are connected.

[0079] 0° position (i.e. closed position): All pins are disconnected.

[0080] Right 45° position (i.e. AC power II position): At this time, pins 23 and 24 are connected.

[0081] In the present invention, the specific implementation is as follows: Figure 5 The conversion switch SA2 is a working mode switch. When the handle of the conversion switch SA1 is in the left 45° position, the input switching mode of the railway communication power supply system is in the manual state; when the handle of the conversion switch SA1 is in the right 45° position, the input switching mode of the railway communication power supply system is in the automatic state.

[0082] In specific implementation, the transfer switch SA2 is an existing transfer switch, and specifically, the transfer switch model LA39-A3-22-CX / K produced by Suzhou Siemens Electric Co., Ltd. can be used. The transfer switch can be customized according to circuit requirements, and the appearance of the transfer switch can be as follows Figure 5 As shown, the on-state of the conversion switch is shown in Table 2 below.

[0083] Table 2:

[0084]

[0085] In Table 2, X indicates on. Normal position 1 is the left 45° position, and position 2 is the right 45° position;

[0086] Left 45° position (ie manual position): At this time, pins 11, 12 and 31, 32 are connected.

[0087] Right 45° position (i.e. automatic position): At this time, pins 23, 24 and 43, 44 are connected.

[0088] In the present invention, in a specific implementation, the AC switching device, which includes contactors 1KM, 2KM and mechanical interlocking, is an electrical component with mature prior art. The specific model of the AC switching device can be the Liangxin NDC1N-9540 AC contactor produced by Shanghai Liangxin Electric Co., Ltd. The AC contactor is a contactor with mechanical interlocking. The electrical circuit diagram of the AC switching device is as follows: Figure 3 As shown. The coil contact marks of contactors 1KM and 2KM are both A1 and A2, specifically distinguished by 1KM-A1 and 2KM-A1; contactors 1KM and 2KM respectively have three groups of normally open contacts (1L1, 2T1), (3L2, 4T2), (5L3, 6T3), and one group of normally closed auxiliary contacts (61, 62);

[0089] It should be noted that when the coil contacts A1 and A2 of contactors 1KM and 2KM are energized (220V), their three groups of normally open contacts (1L1, 2T1), (3L2, 4T2), and (5L3, 6T3) change from normally open to normally closed; similarly, one group of normally closed auxiliary contacts (61, 62) changes from normally closed to normally open.

[0090] In specific implementation, the rated current of the main contact of the Liangxin NDC1N-9540 AC contactor is 95A. The specific power can be selected according to the specific circuit. The AC switching device is not limited to the model specifications of the present invention. As long as it meets Figure 1 Any existing AC switching device having the functions and structure of the above-mentioned AC switching device can be adopted.

[0091] In the present invention, in specific implementation, the relay KA is an existing relay, specifically a relay of model CR-M024DC4L produced by Xinhui Low Voltage Switch Co., Ltd. (ABB). The electrical circuit diagram of the relay is as shown in FIG. Figure 6 The coils of the relay are marked as 13 and 14, and the relay has two groups of normally open contacts (7, 11) and (8, 12), and two groups of normally closed contacts (1, 9) and (2, 10).

[0092] It should be noted that when the coil contacts 13 and 14 of the relay are powered (DC24V), the two groups of normally open contacts (7, 11) and (8, 12) change from normally open to normally closed; similarly, the two groups of normally closed contacts (1, 9) and (2, 10) change from normally closed to normally open. The state of the relay contacts is used to control the AC switching device to perform automatic switching.

[0093] In specific implementation, the CR-M024DC4L relay produced by Xinhui Low Voltage Switch Co., Ltd. (ABB) is a small electromagnetic relay with 4 sets of independent contacts, each set of contacts has a common contact, a normally open contact, and a normally closed contact. The model of the relay is not limited to the model specifications in the present invention, as long as it meets the requirements. Figure 6 Any existing relay having the functions and structures of the above-mentioned relays can be adopted.

[0094] In the present invention, in specific implementation, it also includes: a monitoring module (including four monitoring units J1 to J4);

[0095] The monitoring module is respectively connected to the relay KA, the AC switching device, and the AC transformers 1JC, 2JC, 3JC, 4JC, 5JC and 6JC, and is used to realize real-time monitoring of the input voltage, current, frequency and switch state of the two AC input power supplies. When the monitoring module detects that the two AC input power supplies (i.e., the external power grid, specifically the I-way mains input power supply and the II-way mains input power supply) have a fault (such as input overvoltage, undervoltage, phase failure, wrong phase, etc.), it sends a control signal to the relay KA to control the relay KA to operate and switch the two AC input power supplies (I-way mains input power supply and II-way mains input power supply);

[0096] It should be noted that the monitoring module is a mature monitoring module with popular application in the prior art, and is an existing finished electrical module. The above functions of the monitoring module are functions of the existing finished modules, and will not be repeated here. The monitoring module, for example, can adopt the HKTT monitoring module produced by Tianjin Railway Signal Co., Ltd.

[0097] In specific implementation, when a remote switching operation is performed, the monitoring unit also issues a control command, which is executed by the relay KA.

[0098] In specific implementation, relay KA is a control switch for automatic switching of two power supplies and remote manual switching. When the monitoring unit detects that the external power grid (specifically, mains input power supply I and mains input power supply II) has input overvoltage, undervoltage, phase loss, wrong phase and other faults, the control relay KA is activated to switch the two power supplies, and has the function of priority switching of mains input power supply I; when performing remote switching operations, the control command is also issued by the monitoring unit and executed by relay KA.

[0099] In the present invention, in specific implementation, the monitoring module adopts the HKTT type monitoring module produced by Tianjin Railway Signal Co., Ltd.;

[0100] Monitoring module, including monitoring units J1 to J4;

[0101] The monitoring unit J1 is used to monitor the voltage of the I-way mains input power supply;

[0102] The monitoring unit J2 is used to monitor the current of the I-way mains input power supply;

[0103] Monitoring unit J3, used to monitor the voltage of II-way mains input power supply;

[0104] The monitoring unit J4 is used to monitor the current of the II-way mains input power supply.

[0105] It should be noted that, as mentioned above, the monitoring module is a mature and widely used monitoring module with existing technology, and is an existing finished electrical module. The above-mentioned functions performed by the four monitoring units J1 to J4 included therein are existing functions of the monitoring units in the existing finished modules, and will not be repeated here.

[0106] In specific implementation, the first pin of the monitoring unit J1 is connected to the 1L1 pin of the contactor 1KM in the AC switching device;

[0107] The third pin of the monitoring unit J1 is connected to the 3L2 pin of the contactor 1KM in the AC switching device;

[0108] The 5th pin of the monitoring unit J1 is connected to the 5L3 pin of the contactor 1KM in the AC switching device;

[0109] The 7th pin of the monitoring unit J1 is connected to the N-phase line (e.g., N-phase copper busbar) of the I-way mains input power supply;

[0110] In specific implementation, the first pin of the monitoring unit J2 is connected to the first pin of the current transformer 1JC (the A-phase current transformer) of the I-way mains input power supply;

[0111] The second pin of the monitoring unit J2 is connected to the second pin of the current transformer 1JC (the A-phase current transformer) of the I-way mains input power supply;

[0112] The third pin of the monitoring unit J2 is connected to the first pin of the current transformer 2JC (the B-phase current transformer) of the I-way mains input power supply;

[0113] The 4th pin of the monitoring unit J2 is connected to the 2nd pin of the current transformer 2JC (the B-phase current transformer) of the I-way mains input power supply;

[0114] The 5th pin of the monitoring unit J2 is connected to the 1st pin of the current transformer 3JC (C-phase current transformer) of the I-way mains input power supply;

[0115] The 6th pin of the monitoring unit J2 is connected to the 2nd pin of the current transformer 3JC (C-phase current transformer) of the I-way mains input power supply;

[0116] In specific implementation, the first pin of the monitoring unit J3 is connected to the 1L1 pin of the contactor 2KM in the AC switching device;

[0117] The third pin of the monitoring unit J3 is connected to the 3L2 pin of the contactor 2KM in the AC switching device;

[0118] The 5th pin of the monitoring unit J3 is connected to the 5L3 pin of the contactor 2KM in the AC switching device;

[0119] The 7th pin of the monitoring unit J3 is connected to the N-phase line (e.g., the N-phase copper busbar) of the II-way mains input power supply;

[0120] In specific implementation, the first pin of the monitoring unit J4 is connected to the first pin of the current transformer 4JC (the A-phase current transformer) of the II-way mains input power supply;

[0121] The second pin of the monitoring unit J4 is connected to the second pin of the current transformer 4JC (the A-phase current transformer) of the II-way mains input power supply;

[0122] The third pin of the monitoring unit J4 is connected to the first pin of the current transformer 5JC (the B-phase current transformer) of the II-way mains input power supply;

[0123] The 4th pin of the monitoring unit J4 is connected to the 2nd pin of the current transformer 5JC (the B-phase current transformer) of the II-way mains input power supply;

[0124] The 5th pin of the monitoring unit J4 is connected to the 1st pin of the current transformer 6JC (C-phase current transformer) of the II-way mains input power supply;

[0125] The 6th pin of the monitoring unit J4 is connected to the 2nd pin of the C-phase current transformer 6JC of the II-way mains input power supply.

[0126] In specific implementation, the +12V pin of the CON4 port of the monitoring module is connected to the 14th pin of the relay KA;

[0127] The -12V pin of the CON4 port of the monitoring module is connected to the CON-7 pin of the J24 port of the monitoring module;

[0128] The NO-7 pin of the J24 port of the monitoring module is connected to the 13th pin of the relay KA.

[0129] In order to more clearly understand the present invention, the working principle of the monitoring module is introduced below.

[0130] For the existing finished monitoring module (specifically, the HKTT type monitoring module produced by Tianjin Railway Signal Co., Ltd.), the monitoring unit J2 and the monitoring unit J4 therein are respectively connected to the current monitoring circuit provided in the monitoring module; the monitoring unit J1 and the monitoring unit J3 are respectively connected to the step-down conversion circuit provided in the monitoring module; the step-down conversion circuit is connected to the voltage monitoring circuit provided in the monitoring module; and the monitoring units J1 to J4 are also connected to the frequency monitoring circuit provided in the monitoring module. The current monitoring circuit, the voltage monitoring circuit and the frequency monitoring circuit are respectively connected to the control chip provided in the monitoring module. The connection relationship and the working principle of mutual cooperation between these monitoring units, circuits and control chips are the existing contents of the existing finished monitoring module itself, and are the existing mature and applied technologies, which will not be elaborated here.

[0131] In specific implementation, the monitoring module collects the voltage, current, frequency and other information of the input power supply through the contacts of the four monitoring units J1, J2, J3 and J4 therein. The current information of the input power supply is converted into a 0-20mA current signal by an AC transformer and enters the current monitoring circuit built into the monitoring module. The voltage information of the input power supply is converted into a 0-20mA current signal by a step-down conversion circuit built into the monitoring module and enters the voltage monitoring circuit built into the monitoring module. The frequency information is monitored by the frequency monitoring circuit built into the monitoring module. If these information (voltage information and current information, frequency information, etc. of the input power supply) exceeds the overvoltage value, undervoltage value, overcurrent value, frequency abnormality value, etc. of the input power supply pre-set by the monitoring module, the control chip built into the monitoring module issues a control command to control the coil of the relay KA to be energized or de-energized, and then the contacts of the relay KA control the AC switching device to switch the two power supplies.

[0132] For example: if it is found that the mains power supply I is abnormal and the mains power supply II is normal, the monitoring module controls the relay KA to be energized (specifically through the control chip built into it), and the two groups of normally closed contacts (1, 9) and (2, 10) of the relay KA change from normally closed to normally open, the coil of the contactor 1KM of the AC switching device loses power, and the normally closed contacts of the contactor 1KM close. At the same time, the normally open contacts (7, 11) and (8, 12) of the relay KA change from normally open to normally closed, and the coil of the contactor 2KM of the AC switching device is energized, and the main contacts of the contactor 2KM close. At this time, the input power is converted from the mains power supply I to the mains power supply II, realizing the automatic switching of the two power supplies. If the mains power supply I returns to normal, the monitoring module (specifically the control chip built into it) controls the relay KA to be disconnected, so that the subsequent power-consuming equipment (such as railway communication equipment) in the railway communication power supply system resumes the mains power supply I (i.e., the I priority function).

[0133] It should be noted that the contacts (i.e. pins) +12V and -12V of the CON4 port of the monitoring module can output DC24V power. The J24 port of the monitoring module is a group of auxiliary contacts, in which the contact (i.e. pin) CON-7 is the common terminal, and the contacts (i.e. pins) CON-7 and NO-7 are a group of normally open contacts. When the monitoring module determines that two-way switching is required, the monitoring module controls the contacts (CON-7, NO-7) from normally open to normally closed.

[0134] It should be noted that the monitoring module itself has two control modes, manual mode and automatic mode. In manual mode, the monitoring module can be used to manually select AC power line I or AC power line II. Among them, the manual switching function of the monitoring module, specifically the "AC input selection" manual switching function, can be set to "ACA1 or AC2" two working modes. When set to AC1 working mode, the communication power supply is in AC power line I, and when set to AC2 working mode, the communication power supply is converted to AC power line II).

[0135] It should be noted that when the monitoring module is in manual mode, even if the monitoring units J1, J2, J3, and J4 detect that the AC power input has overvoltage, undervoltage, overcurrent, phase loss, phase error, and frequency abnormality, the monitoring module will not control relay KA to switch, that is, relay KA will not be controlled at this time.

[0136] It should be noted that when the monitoring module is in automatic mode (i.e., normal monitoring state), the voltage, current, frequency and other information of the input power supply can be collected through the contacts (pins) on the monitoring units J1, J2, J3, and J4. After judgment by the monitoring module, the coil of relay KA is further controlled to be energized or de-energized, thereby controlling the conversion of the two mains power lines, mains power line I and mains power line II.

[0137] It should be noted that, in the present invention, the monitoring module provides a complete monitoring, control and protection function for the railway communication power supply system. The manual and automatic switching and remote switching functions of the two AC power supplies are only part of all the functions.

[0138] In order to more clearly understand the present invention, the working principle of the AC switching device is introduced below.

[0139] 1. The coil contacts A1 and A2 of the contactor 1KM of the AC switching device are controlled by the change-over switches SA1 and SA2, the contacts of the relay KA and the contacts of the contactor 2KM.

[0140] The specific control principle is: when the conversion switch SA2 is in the manual position (i.e., the left 45° position), the contacts (i.e., pins) 11 and 12 of the conversion switch SA2 are in the normally closed position, the contacts (i.e., pins) 23 and 24 of the conversion switch SA2 are in the normally open position, and the contacts (i.e., pins) 61 and 62 of the contactor 2KM are in the normally closed position. At this time, when the rotary conversion switch SA1 is in the mains I position (i.e., the left 45° position), the contacts (i.e., pins) 13 and 14 of the conversion switch SA1 change from normally open contacts to normally closed contacts, the coil of the contactor 1KM is energized, and the contactor 1KM is attracted;

[0141] When the transfer switch SA2 is in the automatic position (i.e., the right 45° position), the contacts (i.e., pins) 11 and 12 of the transfer switch SA2 are in the normally open position, the contacts (i.e., pins) 23 and 24 of the transfer switch SA2 are in the normally closed position, and the contacts (i.e., pins, contacts) 61 and 62 of the contactor 2KM are in the normally closed position. At this time, if the monitoring module detects that the mains I power supply is normal, the contacts (i.e., pins) 1, 9 and 2, 10 of the relay KA are in the normally closed position, the coil of the contactor 1KM is energized, and the contactor 1KM is closed;

[0142] 2. The coil contacts A1 and A2 of contactor 2KM are controlled by switching switches SA1 and SA2, the contacts of relay KA and the contacts of contactor 1KM.

[0143] The specific control principle is: when the conversion switch SA2 is in the manual position (i.e., the left 45° position), the contacts (i.e., pins) 31 and 32 of the conversion switch SA2 are in the normally closed position, the contacts (i.e., pins) 43 and 44 of the conversion switch SA2 are in the normally open position, and the contacts (i.e., pins) 61 and 62 of the contactor 1KM are in the normally closed position. At this time, when the rotary conversion switch SA1 is in the mains II position (i.e., the right 45° position), the contacts (i.e., pins) 23 and 24 of the conversion switch SA1 change from normally open contacts to normally closed contacts, the coil of the contactor of the AC switching device 1KM is energized, and the contactor 1KM is closed;

[0144] When the conversion switch SA2 is in the automatic position (i.e., the right 45° position), the contacts (i.e., pins) 11 and 12 of the conversion switch SA2 are in the normally open position, the contacts (i.e., pins) 23 and 24 of the conversion switch SA2 are in the normally closed position, and the contacts (i.e., pins, contacts) 61 and 62 of the contactor 2KM are in the normally closed position. At this time, if the monitoring module detects that the mains I power supply is abnormal and the mains II power supply is normal, the monitoring module controls the relay KA to close, and the contacts (i.e., pins, contacts) 7, 11 and 8, 12 of the relay KA change from normally open contacts to normally closed contacts, the coil of the contactor 2KM is energized, and the contactor 2KM closes;

[0145] Based on the input power switching circuit provided by the present invention, the present invention further provides a railway communication power supply system, which includes the input power switching circuit as described above, and a plurality of railway communication devices;

[0146] Railway communication equipment, connected to the input power switching circuit;

[0147] Railway communication equipment is the subsequent power-consuming equipment in the input power switching circuit.

[0148] In order to more clearly understand the technical solution of the present invention, the working principle of the present invention is explained below by taking the working mode as an example.

[0149] 1. How the circuit works when it is powered on for the first time

[0150] When the switch SA2 is in the automatic state and the monitoring module is in the automatic mode (i.e., the normal monitoring state), after both mains input power supplies are sent to the railway communication power supply system, the circuit breakers QF1 and QF2 are closed, and the monitoring units J1, J2, J3, and J4 of the monitoring module will automatically detect the input power supply for over-voltage, under-voltage, phase failure, and phase loss, and the monitoring module will determine whether the input power supply meets the requirements. The monitoring module controls the AC switching device to operate through the relay KA, and outputs the power supply that meets the requirements to the subsequent railway communication equipment for use. Among them, if both power supplies meet the requirements, input power supply I is selected for output, and the other is reserved (I is preferred).

[0151] The power supply that meets the requirements is, for example, an input voltage that satisfies: AC 380V (-20% to +20%), and a frequency that satisfies: 50Hz±5Hz.

[0152] 2. The working mode of the input power automatically switching from the mains input power of line I to the mains input power of line II

[0153] When both power grids (i.e., mains input power supply I and mains input power supply II) are normal, the AC switching device works at power supply I. At this time, if any faults such as over-voltage, under-voltage, power failure, or phase failure occur in the input power supply I, the voltage and current information of channel I collected by the monitoring units J1 and J2 exceed the set alarm value, and the monitoring module controls the contacts (CON-7, NO-7) of port J24 on it to be connected, the coil of relay KA is energized and attracted, its normally closed contacts 1-9 and 2-10 are disconnected, and the normally open contacts 7-11 and 8-12 are connected, the coil of contactor 1KM in the AC switching device loses power, and the auxiliary normally closed contacts 61-62 of contactor 1KM are closed. At this time, the coil of contactor 2KM in the AC switching device is energized, and contactor 2KM is attracted and switched to power supply II.

[0154] Similarly, when a power failure occurs in line II, the action process is the same.

[0155] 3. Manually transfer the input power from I-way mains input power to II-way mains input power

[0156] When manual conversion is required (at this time, both input power supplies of channels I and II should be normal), the operation can be performed directly through the conversion switch SA1.

[0157] When the I-way mains input power supply is working, if it is necessary to switch to the II-way mains input power supply, the conversion switch SA2 can be placed in the "manual" position, the contacts 11-12 and 31-32 of the conversion switch SA2 are connected, and the contacts 23-24 and 43-44 are disconnected, and the conversion switch SA1 is rotated to the "mains II" position (i.e. the right 45° position). At this time, the contacts 13-14 of the conversion switch SA1 are disconnected, and the contacts 23-24 are connected. The coil of the contactor 1KM in the AC switching device loses power, and the auxiliary normally closed contacts 61-62 of the contactor 1KM are closed, and the coil of the contactor 2KM in the AC switching device is energized, and the contactor 2KM is energized. At this time, the input power is transferred from the I-way mains input power supply to the II-way mains input power supply.

[0158] 4. The monitoring module is used for manual control to transfer the input power from the mains input power supply of route I to the mains input power supply of route II.

[0159] When manual switching is performed through the monitoring module, the conversion switch SA2 is placed in the "automatic" position, the monitoring module is in the "manual" mode, and the "AC input selection" of the monitoring module is set to: "AC2". At this time, the monitoring module controls the contacts (CON-7, NO-7) of the port J24 on it to be connected, the relay KA coil is energized, the normally closed contacts 1-9 and 2-10 of the relay KA are disconnected, and the normally open contacts 7-11 and 8-12 are connected. The coil of the contactor 1KM in the AC switching device loses power, and the auxiliary normally closed contacts 61-62 of the contactor 1KM are closed. At this time, the coil of the contactor 2KM in the AC switching device is energized, and the contactor 2KM is energized and transferred to the II power supply.

[0160] 5. Working method of manually transferring input power from II-way mains input power to I-way mains input power

[0161] When the II-way mains input power supply is working, if it is necessary to switch to the I-way mains input, the conversion switch SA2 can be placed in the "manual" position, the contacts 11-12 and 31-32 of the conversion switch SA2 are connected, and the contacts 23-24 and 43-44 are disconnected, and the conversion switch SA1 is rotated to "mains I" (i.e. the left 45° position). At this time, the contacts 13-14 of the conversion switch SA1 are connected, and the contacts 23-24 are disconnected, the contactor 2KM coil in the AC switching device loses power, and the auxiliary normally closed contacts 61-62 of the contactor 2KM are closed, the contactor 1KM coil in the AC switching device is energized, and the contactor 1KM is energized. At this time, the input power is transferred from the II-way mains input power supply to the I-way mains input power supply.

[0162] 6. The monitoring module is used for manual control to transfer the input power from the II-way mains input power to the I-way mains input power.

[0163] When switching is performed manually through the monitoring module, the conversion switch SA2 is placed in the "automatic" position, the monitoring module is in the "manual" mode, and the working mode is set to "AC1 working mode" through the "AC input selection" manual switching function of the monitoring module. At this time, the monitoring module controls the contacts (CON-7, NO-7) of the port J24 on it to be disconnected, the relay KA coil does not operate, the normally closed contacts 1-9 and 2-10 of the relay KA are connected, and the normally open contacts 7-11 and 8-12 are disconnected, the coil of the contactor 2KM in the AC switching device loses power, and the auxiliary normally closed contacts 61-62 of the contactor 2KM are closed. At this time, the coil of the contactor 1KM in the AC switching device is energized, and the contactor 1KM is attracted and transferred to the I power supply.

[0164] 7. Working mode of connecting to generator F power supply

[0165] When it is necessary to access the power supply of generator F, directly connect the output cable of the generator to the input terminal of circuit breaker QF4. When the generator is working normally, the circuit breaker QF3 can be disconnected and the mechanical interlocking device can be moved to the position where the circuit breaker QF4 can be closed. At this time, the circuit breaker QF4 can be closed and the power is supplied by the generator.

[0166] After inspection, it is found that the circuit provided by the present invention mainly uses low-voltage electrical components, has a modular design, stable operation, high reliability, and low failure rate, and can be reliably applied to railway communication power supply system equipment.

[0167] Compared with the prior art, the input power switching circuit and railway communication power supply system provided by the present invention have the following beneficial effects:

[0168] The present invention can not only access two input power sources, but also perform remote switching of the two input power sources and access to a generator power source.

[0169] 2. Based on the present invention, not only manual and automatic switching can be realized, but also the switching of the two power supplies can be remotely controlled. It has an independent generator power access interface. When the generator power supply needs to be connected, the AC input circuit breaker is disconnected only after the generator works normally, and there is no risk of power failure of the back-end electrical equipment.

[0170] It should be noted that the risk of power outage is: in an unmanned communication station, in extreme cases when there are problems with both input power sources at the same time and it is necessary to temporarily connect to the generator for power supply, if there is no separate generator interface, it is necessary to disconnect all input circuit breakers at the same time and remove the wiring of one power supply before connecting to the generator. Even if the power is restored, it is necessary to cut off the power to restore the original wiring; and when power outage maintenance is required, if the maintenance personnel cannot arrive at the site in time for manual switching, and there is a problem with the automatic switching detection circuit, the communication power system will have no input power. Once the battery is fully discharged, all railway communication equipment will lose power instantly, causing unpredictable situations such as the possible stopping of the running train, which is not allowed by the railway company.

[0171] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An input power switching circuit, characterized in that: include: AC switching device, circuit breakers QF1~QF4 and transfer switches SA1~SA2; The input terminals of the circuit breakers QF1 and QF2 are connected to two AC input power supplies accordingly; Two AC input power supplies, including I mains input power supply and II mains input power supply; The output terminals of the circuit breakers QF1 and QF2 are connected to the circuit breaker QF3 through the AC switching device; The AC switching device is used to switch two AC input power sources into one AC power source and then connect it to the circuit breaker QF3; The output terminal of the circuit breaker QF3 is connected to the power supply input terminal of the subsequent electrical equipment; The input terminal of the circuit breaker QF4 is connected to the output terminal of the power supply of the generator F; The output terminal of the circuit breaker QF4 is connected to the power supply input terminal of the subsequent electrical equipment.

2. The input power switching circuit according to claim 1, wherein: The 1st, 3rd and 5th pins of the input terminal of the circuit breaker QF1 are respectively connected to the A, B and C phase power lines of the I-way mains input power supply; The 1st, 3rd and 5th pins of the input end of the circuit breaker QF2 are respectively connected to the A, B and C phase power lines of the II-way AC input power supply.

3. The input power switching circuit according to claim 1, wherein: AC switching device, including contactor 1KM~2KM; The output ends of the circuit breakers QF1 and QF2 are respectively connected to the contactor 1KM and the contactor 2KM in the AC switching device.

4. The input power switching circuit according to claim 3, characterized in that: The output pins 2, 4 and 6 of the circuit breaker QFI pass through the AC transformers 1JC, 2JC and 3JC respectively, and are connected to the 1L1, 3L2 and 5L3 pins of the 1KM contactor in the AC switching device. The 2nd, 4th and 6th pins of the output end of the circuit breaker QF2 pass through the AC transformers 4JC, 5JC and 6JC respectively, and are connected to the 1L1, 3L2 and 5L3 pins of the 2KM contactor in the AC switching device.

5. The input power switching circuit according to claim 1, wherein: The output terminals of contactors 1KM and 2KM in the AC switching device are connected to the input terminal of circuit breaker QF3 after merging; Pins 1, 3, and 5 of the input terminal of circuit breaker QF4 are connected to the A, B, and C phase power lines of the generator F power supply; The 2nd, 4th and 6th pins of the output terminal of the circuit breaker QF4 are respectively connected to the 2nd, 4th and 6th pins of the output terminal of the circuit breaker QF3 and then connected to the subsequent electrical equipment to supply power to the subsequent electrical equipment.

6. The input power switching circuit according to any one of claims 1 to 5, characterized in that: For the AC switching device, the 62nd pin of contactor 2KM is connected to the 1L1 pin of contactor 1KM; Pin 61 of contactor 2KM is connected to coil contact A2 of contactor 1KM; The coil contact A1 of the contactor 1KM is connected to the 13th pin of the change-over switch SA1 and the 10th pin of the relay 1KA respectively; The 14th pin of the transfer switch SA1 is connected to the 11th pin of the transfer switch SA2; The second pin of the relay KA is connected to the 23rd pin of the transfer switch SA2; The 24th pin of the transfer switch SA2 is connected to the 9th pin of the relay KA; The first pin of the relay KA is connected to the 12th pin of the transfer switch SA2; For the AC switching device, the 62nd pin of contactor 1KM is connected to the 1L1 pin of contactor 2KM; Pin 61 of contactor 1KM is connected to coil contact A2 of contactor 2KM; The coil contact A1 of the contactor 2KM is connected to the 23rd pin of the change-over switch SA1 and the 12th pin of the relay KA respectively; The 24th pin of the transfer switch SA1 is connected to the 31st pin of the transfer switch SA2; The 8th pin of the relay KA is connected to the 43rd pin of the transfer switch SA2; The 44th pin of the transfer switch SA2 is connected to the 11th pin of the relay KA; The 7th pin of the relay KA is connected to the 32nd pin of the transfer switch SA2.

7. The input power switching circuit according to claim 6, wherein: The 12th pin of the conversion switch SA2 is connected to the N-phase line of any one of the two AC input power sources; The 32nd pin of the conversion switch SA2 is connected to the N-phase line of any one of the two AC input power sources.

8. The input power switching circuit according to any one of claims 1 to 5, characterized in that: Also includes: Monitoring module; The monitoring module is respectively connected with the relay KA, the AC switching device, and the AC transformers 1JC, 2JC, 3JC, 4JC, 5JC and 6JC.

9. The input power switching circuit according to claim 8, wherein: Monitoring module, including monitoring units J1 to J4; The first pin of the control unit J1 is connected to the 1L1 pin of the contactor 1KM in the AC switching device; The third pin of the monitoring unit J1 is connected to the 3L2 pin of the contactor 1KM in the AC switching device; The 5th pin of the monitoring unit J1 is connected to the 5L3 pin of the contactor 1KM in the AC switching device; The 7th pin of the monitoring unit J1 is connected to the N-phase line of the I-way mains input power supply; In specific implementation, the first pin of the monitoring unit J2 is connected to the first pin of the current transformer 1JC of the I-way mains input power supply; The second pin of the monitoring unit J2 is connected to the second pin of the current transformer 1JC of the I-way mains input power supply; The third pin of the monitoring unit J2 is connected to the first pin of the current transformer 2JC of the I-way mains input power supply; The 4th pin of the monitoring unit J2 is connected to the 2nd pin of the current transformer 2JC of the I-way mains input power supply; The 5th pin of the monitoring unit J2 is connected to the 1st pin of the current transformer 3JC of the I-way mains input power supply; The 6th pin of the monitoring unit J2 is connected to the 2nd pin of the current transformer 3JC of the I-way mains input power supply; In specific implementation, the first pin of the monitoring unit J3 is connected to the 1L1 pin of the contactor 2KM in the AC switching device; The third pin of the monitoring unit J3 is connected to the 3L2 pin of the contactor 2KM in the AC switching device; The 5th pin of the monitoring unit J3 is connected to the 5L3 pin of the contactor 2KM in the AC switching device; The 7th pin of the monitoring unit J3 is connected to the N-phase line of the II-way mains input power supply; In specific implementation, the first pin of the monitoring unit J4 is connected to the first pin of the current transformer 4JC of the II-way mains input power supply; The second pin of the monitoring unit J4 is connected to the second pin of the current transformer 4JC of the II-way mains input power supply; The third pin of the monitoring unit J4 is connected to the first pin of the current transformer 5JC of the II-way mains input power supply; The 4th pin of the monitoring unit J4 is connected to the 2nd pin of the current transformer 5JC of the II-way mains input power supply; The 5th pin of the monitoring unit J4 is connected to the 1st pin of the current transformer 6JC of the II-way mains input power supply; The 6th pin of the monitoring unit J4 is connected to the 2nd pin of the C-phase current transformer 6JC of the II-way mains input power supply; The +12V pin of the CON4 port of the monitoring module is connected to the 14th pin of the relay KA; The -12V pin of the CON4 port of the monitoring module is connected to the CON-7 pin of the J24 port of the monitoring module; The NO-7 pin of the J24 port of the monitoring module is connected to the 13th pin of the relay KA.

10. A railway communication power supply system, characterized in that: comprising an input power switching circuit as claimed in any one of claims 1 to 9, and a plurality of railway communication devices; Railway communication equipment, connected to the input power switching circuit; Railway communication equipment is the subsequent power-consuming equipment in the input power switching circuit.

Images