An input redundancy circuit

Abstract

An input redundancy circuit, comprising: input voltage 1, input voltage 2, intelligent switching unit, auxiliary power supply unit and key power supply unit, the intelligent switching unit is connected with input voltage 1, input voltage 2 and auxiliary power supply unit, and any one of input voltage 1 and input voltage 2 is connected to key power supply unit; the intelligent switching unit comprises relay 1, relay 2, double-input control circuit and electromagnetic interference filter 3; the output end of input voltage 1 is connected to the normally closed contact A2 of relay 1 and the normally closed contact B2 of relay 2, the output end of input voltage 2 is connected to the normally open contact A3 of relay 1 and the normally open contact B3 of relay 2, and relay 1 contact A1 and relay 2 contact B1 are connected with key power supply circuit through electromagnetic interference filter 3.The present application can simplify the circuit structure, effectively reduce the space occupation, not only can meet the demand of high requirement for power stability, but also can reduce the cost and improve the space utilization.

Description

Technical Field

[0001] This invention relates to the field of switching power supply technology, and more specifically to an input redundancy circuit. Background Technology

[0002] With the increasing prevalence of network communication scenarios, more stringent requirements have been placed on the reliability of communication equipment. A crucial factor in ensuring the reliability of communication equipment is the stable and reliable operation of its power supply. If the power grid supplying the communication equipment experiences a fault or power outage, the equipment will malfunction. Furthermore, internal faults in the power supply itself will also prevent the equipment from functioning properly. Therefore, redundant backups of the power supply are necessary to prevent power outages caused by power failures.

[0003] In the current technology, the main redundancy backup scheme for the power supply of communication equipment is a 1+1 power supply or N+N power supply. Under this scheme, the failure of any one power supply will not affect the operation of the communication equipment. However, this method uses a large number of power supplies, which will occupy a large space in the communication equipment, and the utilization efficiency of each power supply is not high, which will result in a waste of electricity.

[0004] To address the aforementioned technical problems, patent number 2020111582124, entitled "An Input Redundancy Circuit and Method," discloses an input redundancy circuit comprising an input power supply unit, a voltage detection unit, a control unit, and a selection unit. The input power supply unit is connected to both the voltage detection unit and the selection unit. The voltage detection unit is connected to the control unit, and the control unit is connected to the selection unit. Specifically: the input power supply unit is used to input at least two power sources to the selection unit; the voltage detection unit is used to detect whether the voltages of the at least two power sources are suitable for power supply and sends the detection results to the control unit; the control unit is used to receive the detection results, select from the at least two power sources based on the detection results, and send the selection result to the selection unit; the selection unit is used to receive the selection result and input the power source corresponding to the selection result to the electromagnetic interference (EMI) and filtering / rectifying circuit connected to the input redundancy circuit to supply power to the powered device.

[0005] The aforementioned patents can address the problem of high cost and low efficiency of redundant backup power supplies due to a large number of redundant backup power supplies. However, the selection unit in these patents requires the use of numerous relays in combination. This method increases the complexity of the circuit structure and space requirements, resulting in high cost, complex control, long switching time, and high power consumption. Summary of the Invention

[0006] To address the aforementioned technical problems, this technical solution provides an input redundancy circuit that uses only two relays as switching devices. Compared with existing technologies, it has the advantages of low cost, low power consumption, and fast switching speed, effectively solving the above problems.

[0007] This invention is achieved through the following technical solution:

[0008] An input redundancy circuit includes: input voltage 1, input voltage 2, intelligent switching unit, auxiliary power supply unit, and critical power supply unit. The intelligent switching unit is connected to input voltage 1, input voltage 2, and auxiliary power supply unit, and connects either input voltage 1 or input voltage 2 to the critical power supply unit. The intelligent switching unit includes relay 1, relay 2, dual-input control circuit, and electromagnetic interference filter 3. The output terminal of input voltage 1 is connected to the normally closed contact A2 of relay 1 and the normally closed contact B2 of relay 2. The output terminal of input voltage 2 is connected to the normally open contact A3 of relay 1 and the normally open contact B3 of relay 2. Contact A1 of relay 1 and contact B1 of relay 2 are connected to the critical power supply circuit through electromagnetic interference filter 3.

[0009] Furthermore, both input voltage 1 and input voltage 2 can be set to be the primary input and the backup input by default: when input voltage 1 is set to be the primary input by default, input voltage 2 is the backup input, and when input voltage 2 is set to be the primary input by default, input voltage 1 is the backup input.

[0010] Furthermore, when input voltage 1 is a normal voltage and input voltage 2 is an abnormal voltage, input voltage 1 will be connected to the output of the relay, and input voltage 2 will be isolated from the relay output and input voltage 1 due to the disconnection of its corresponding set of contacts.

[0011] When input voltage 2 is a normal voltage and input voltage 1 is an abnormal voltage, input voltage 2 will be connected to the output of the relay, and input voltage 1 will be isolated from the relay output and input voltage 2 due to the disconnection of its corresponding set of contacts;

[0012] When both input voltage 1 and input voltage 2 are normal voltages, the main input will be connected to the output of the relay, and the backup input will be isolated from the relay output circuit and the main input voltage due to the disconnection of its corresponding set of contacts.

[0013] When the main input voltage deteriorates, or there is a power outage or over / under voltage, the dual-input control circuit will send a control signal to drive the relay to switch and connect the backup input voltage to the relay output.

[0014] Furthermore, the input voltage 1, after passing through the electromagnetic interference filter 1 and the detection circuit 1, is connected to the normally closed contact A2 of relay 1 and the normally closed contact B2 of relay 2; the input voltage 2, after passing through the electromagnetic interference filter 2 and the detection circuit 2, is connected to the normally open contact A3 of relay 1 and the normally open contact B3 of relay 2; the electromagnetic interference filter 1 and the electromagnetic interference filter 2 filter the input voltage 1 and the input voltage 2 respectively, and the electromagnetic interference filter 3 filters the output circuit of the relay; the combination of the electromagnetic interference filter 1, the electromagnetic interference filter 2 and the electromagnetic interference filter 3 filters the entire circuit.

[0015] Furthermore, the detection circuit 1 detects whether the input voltage 1 is a normal input voltage and provides the detection signal 1 to the dual-input control circuit; the detection circuit 2 detects whether the input voltage 2 is a normal input voltage and provides the detection signal 2 to the dual-input control circuit; the dual-input control circuit determines whether the detection signal 1 and the detection signal 2 are normal input voltages, and then controls the relay circuit to switch from one of the input voltage 1 and the input voltage 2 to the other or keep the current state unchanged.

[0016] Furthermore, both relay 1 and relay 2 are single-pole double-throw relays, and the input voltage 1 is connected to the normally closed contacts of relay 1 and relay 2.

[0017] When the input voltage 1 is powered normally, the input voltage 1 is directly connected to the electromagnetic interference filter 3 circuit. The key power supply part works normally and supplies power to the dual input control circuit, relay drive circuit 1, relay drive circuit 2, detection circuit 1, and detection circuit 2.

[0018] When input voltage 1 is not powered and only input voltage 2 is normally input, the auxiliary power supply unit is connected to input voltage 2. The auxiliary power supply provides auxiliary power to the dual-input control circuit, relay drive circuit 2, and detection circuit 2, ensuring that relay 1 and relay 2 can switch to input voltage 2 when only input voltage 2 is powered.

[0019] Furthermore, the input voltage 1 and input voltage 2 can be two AC input voltages, one AC input voltage and one DC input voltage, or two DC input voltages.

[0020] Furthermore, the relays 1 and 2 may also be a combination of a double-pole double-throw relay and a single-pole double-throw relay, or a combination of multiple other types of relays, or a combination of other types of contactors, or a combination of power switches.

[0021] Furthermore, the dual-input control circuit is controlled by a microcontroller chip or by a circuit built with analog devices; and the microcontroller chip used in the dual-input control circuit is not limited to sharing a microcontroller chip with the control circuit of the input part of the key power supply unit, but can also use a separate microcontroller chip. Beneficial effects

[0022] The input redundancy circuit proposed in this invention has the following advantages compared with the prior art:

[0023] This technical solution uses only two relays as switching devices. By setting one of the two default inputs to be the main input and the other to be the backup input, it is more flexible and applicable. It can switch even when all or only one of the two inputs has input voltage. It is suitable for medium and high power applications. The relays used are two single-pole double-throw relays, which are safe, simple and easy to control. The relays have the characteristics of low power consumption and low heat generation during long-term operation. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall circuit structure of the present invention.

[0025] Figure 2 This is a schematic diagram of the relay's state when input voltage 2 is connected to the critical power supply in this invention. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. The described embodiments are merely some embodiments of the present invention, and not all embodiments. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the design concept of the present invention should fall within the protection scope of the present invention. Example

[0027] like Figure 1 As shown, an input redundancy circuit includes: input voltage 1, input voltage 2, intelligent switching unit, auxiliary power supply unit and key power supply unit. The intelligent switching unit includes relay 1, relay 2, dual-input control circuit and electromagnetic interference filter 3.

[0028] Input voltage 1 passes through electromagnetic interference filter 1 and detection circuit 1 in sequence and is then connected to normally closed contact A2 of relay 1 and normally closed contact B2 of relay 2; input voltage 2 passes through electromagnetic interference filter 2 and detection circuit 2 in sequence and is then connected to normally open contact A3 of relay 1 and normally open contact B3 of relay 2; contact A1 of relay 1 and contact B1 of relay 2 are connected to the critical power supply circuit through electromagnetic interference filter 3.

[0029] Both input voltage 1 and input voltage 2 can be set as the primary input and the backup input by default: when input voltage 1 is set as the primary input by default, input voltage 2 is the backup input, and when input voltage 2 is set as the primary input by default, input voltage 1 is the backup input.

[0030] Furthermore, when input voltage 1 is a normal voltage and input voltage 2 is an abnormal voltage, input voltage 1 will be connected to the output of the relay, and input voltage 2 will be isolated from the relay output and input voltage 1 due to the disconnection of its corresponding set of contacts.

[0031] When input voltage 2 is a normal voltage and input voltage 1 is an abnormal voltage, input voltage 2 will be connected to the output of the relay, and input voltage 1 will be isolated from the relay output and input voltage 2 due to the disconnection of its corresponding set of contacts;

[0032] When both input voltage 1 and input voltage 2 are normal voltages, the main input will be connected to the output of the relay, and the backup input will be isolated from the relay output circuit and the main input voltage due to the disconnection of its corresponding set of contacts.

[0033] When the main input voltage deteriorates, or there is a power outage or over / under voltage, the dual-input control circuit will send a control signal to drive the relay to switch and connect the backup input voltage to the relay output.

[0034] Electromagnetic interference filter 1 and electromagnetic interference filter 2 filter input voltage 1 and input voltage 2 respectively, and electromagnetic interference filter 3 filters the output circuit of the relay; electromagnetic interference filter 1, electromagnetic interference filter 2 and electromagnetic interference filter 3 are combined to filter the entire circuit.

[0035] The input terminal of detection circuit 1 is connected to electromagnetic interference filter 1, and the output terminal of detection circuit 1 is connected to dual-input control circuit. It detects whether input voltage 1 is a normal input voltage and provides the detection signal 1 to the dual-input control circuit. The input terminal of detection circuit 2 is connected to electromagnetic interference filter 2, and the output terminal of detection circuit 2 is connected to dual-input control circuit. Detection circuit 2 detects whether input voltage 2 is a normal input voltage and provides the detection signal 2 to the dual-input control circuit.

[0036] The output terminals of the dual-input control circuit are connected to the K1 key of relay 1 and the K2 key of relay 2 via drive circuit 1 and drive circuit 2, respectively. After receiving detection signal 1 and detection signal 2 from detection circuit 1 and detection circuit 2, the dual-input control circuit determines whether detection signal 1 and detection signal 2 are normal input voltages, and then controls the relay circuit to switch from one of input voltage 1 and input voltage 2 to the other or maintain the current state.

[0037] Both relay 1 and relay 2 are single-pole double-throw relays, and the input voltage 1 is connected to the normally closed contacts of relay 1 and relay 2.

[0038] When input voltage 1 is normally supplied, it is directly connected to the electromagnetic interference filter 3 circuit. The critical power supply section works normally, supplying power to the dual-input control circuit, relay drive circuit 1, relay drive circuit 2, detection circuit 1, and detection circuit 2. Relay status reference... Figure 2 .

[0039] When input voltage 1 is not powered, and only input voltage 2 is normally supplied, the auxiliary power supply unit connects to input voltage 2. The auxiliary power supply provides auxiliary power to the dual-input control circuit, relay drive circuit 2, and detection circuit 2, ensuring that relays 1 and 2 can switch to input voltage 2 when only input voltage 2 is supplied. (Relay status reference...) Figure 2 .

[0040] The relay circuit in this example consists of two single-pole double-throw relays, each containing two contact paths (A1-A2-A3 and B1-B2-B3) and two coils (K1 and K2). When coils K1 and K2 are not energized, the normally closed contacts (A1-A2 and B1-B2) are closed, and the contacts (A1-A3 and B1-B3) are open. When coils K1 and K2 are energized, the contacts (A1-A3 and B1-B3) are closed, and the contacts (A1-A2 and B1-B2) are open.

[0041] The relay used in this embodiment is a PCB board soldering type. This product has the advantages of small size, light weight, low coil drive power, and low vibration during operation, making it particularly suitable for use in integrated PCB main circuits.

[0042] When only input voltage 2 has a normal input voltage, an auxiliary power supply is required to supply power to the detection circuit, input control circuit and relay drive circuit to ensure that the relay can switch smoothly to input 2.

[0043] This embodiment uses two relays as the switching device. Relays have advantages such as low cost, low power consumption, and fast switching speed. The relays used in this embodiment can switch not only AC circuits but also high-voltage DC circuits.

[0044] The input voltage 1 and input voltage 2 can be two AC input voltages, one AC input voltage and one DC input voltage, or two DC input voltages.

[0045] In addition to the combination of two single-pole double-throw relays as described above, relays 1 and 2 can also be a combination of a double-pole double-throw relay and a single-pole double-throw relay, or a combination of multiple other types of relays, or a combination of other types of contactors, or a combination of power switches.

[0046] The dual-input control circuit is controlled by a microcontroller chip or by a circuit built with analog devices. The microcontroller chip used in the dual-input control circuit is not limited to sharing a microcontroller chip with the control circuit of the input part of the key power supply unit; a separate microcontroller chip can also be used.

Claims

1. An input redundancy circuit, comprising: The system comprises an input voltage 1, an input voltage 2, an intelligent switching unit, an auxiliary power supply unit, and a critical power supply unit. The intelligent switching unit is connected to the input voltage 1, the input voltage 2, and the auxiliary power supply unit, and connects either the input voltage 1 or the input voltage 2 to the critical power supply unit. The intelligent switching unit includes a relay 1, a relay 2, a dual-input control circuit, and an electromagnetic interference filter 3. The output terminal of the input voltage 1 is connected to the normally closed contact A2 of the relay 1 and the normally closed contact B2 of the relay 2. The output terminal of the input voltage 2 is connected to the normally open contact A3 of the relay 1 and the normally open contact B3 of the relay 2. Contacts A1 of the relay 1 and B1 of the relay 2 are connected to the critical power supply circuit through the electromagnetic interference filter 3.

2. The input redundancy circuit according to claim 1, characterized in that: Both input voltage 1 and input voltage 2 can be set as the primary input and the backup input by default: when input voltage 1 is set as the primary input, input voltage 2 is the backup input, and when input voltage 2 is set as the primary input, input voltage 1 is the backup input.

3. The input redundancy circuit according to claim 2, characterized in that: When input voltage 1 is a normal voltage and input voltage 2 is an abnormal voltage, input voltage 1 will be connected to the output of the relay, and input voltage 2 will be isolated from the relay output and input voltage 1 due to the disconnection of its corresponding set of contacts; When input voltage 2 is a normal voltage and input voltage 1 is an abnormal voltage, input voltage 2 will be connected to the output of the relay, and input voltage 1 will be isolated from the relay output and input voltage 2 due to the disconnection of its corresponding set of contacts; When both input voltage 1 and input voltage 2 are normal voltages, the main input will be connected to the output of the relay, and the backup input will be isolated from the relay output circuit and the main input voltage due to the disconnection of its corresponding set of contacts. When the main input voltage deteriorates, or there is a power outage or over / under voltage, the dual-input control circuit will send a control signal to drive the relay to switch and connect the backup input voltage to the relay output.

4. The input redundancy circuit according to claim 1, characterized in that: The input voltage 1, after passing through the electromagnetic interference filter 1 and the detection circuit 1, is connected to the normally closed contact A2 of relay 1 and the normally closed contact B2 of relay 2; the input voltage 2, after passing through the electromagnetic interference filter 2 and the detection circuit 2, is connected to the normally open contact A3 of relay 1 and the normally open contact B3 of relay 2; the electromagnetic interference filter 1 and the electromagnetic interference filter 2 filter the input voltage 1 and the input voltage 2 respectively, and the electromagnetic interference filter 3 filters the output circuit of the relay; the electromagnetic interference filter 1, the electromagnetic interference filter 2 and the electromagnetic interference filter 3 together filter the entire circuit.

5. An input redundancy circuit according to claim 4, characterized in that: The detection circuit 1 detects whether the input voltage 1 is a normal input voltage and provides the detection signal 1 to the dual-input control circuit; the detection circuit 2 detects whether the input voltage 2 is a normal input voltage and provides the detection signal 2 to the dual-input control circuit; the dual-input control circuit determines whether the detection signal 1 and the detection signal 2 are normal input voltages, and then controls the relay circuit to switch from one of the input voltage 1 and the input voltage 2 to the other or keep the current state unchanged.

6. An input redundancy circuit according to claim 5, characterized in that: Both relay 1 and relay 2 are single-pole double-throw relays, and the input voltage 1 is connected to the normally closed contacts of relay 1 and relay 2. When the input voltage 1 is powered normally, the input voltage 1 is directly connected to the electromagnetic interference filter 3 circuit. The key power supply part works normally and supplies power to the dual input control circuit, relay drive circuit 1, relay drive circuit 2, detection circuit 1, and detection circuit 2. When input voltage 1 is not powered and only input voltage 2 is normally input, the auxiliary power supply unit is connected to input voltage 2. The auxiliary power supply provides auxiliary power to the dual-input control circuit, relay drive circuit 2, and detection circuit 2, ensuring that relay 1 and relay 2 can switch to input voltage 2 when only input voltage 2 is powered.

7. An input redundancy circuit according to claim 1, characterized in that: The input voltage 1 and input voltage 2 are two AC input voltages, or one AC input voltage and one DC input voltage, or two DC input voltages.

8. An input redundancy circuit according to claim 1, characterized in that: The relays 1 and 2 may be a combination of a double-pole double-throw relay and a single-pole double-throw relay, or a combination of contactors, or a combination of power switches.

9. An input redundancy circuit according to claim 1, characterized in that: The dual-input control circuit is controlled by a microcontroller chip or by a circuit built with analog devices; and the microcontroller chip used in the dual-input control circuit is not limited to sharing a microcontroller chip with the control circuit of the input part of the key power supply unit, or using a separate microcontroller chip.

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