A motor protector wiring structure for a dilution fan of a thermal power plant

Abstract

The utility model relates to motor power supply control technical field discloses a kind of dilution fan motor protector wiring structure, including main power supply circuit and control circuit, power supply in main power supply circuit is connected to first contactor main contact and second contactor main contact respectively through circuit breaker, and then connect corresponding first dilution fan and second dilution fan again.Control circuit includes dilution fan selection circuit, fan reset control circuit and motor protector.Dilution fan selection circuit one end is connected with second motor protector normally closed contact point, and other end is connected with power supply negative pole.Fan reset control circuit is connected with motor protector control input port.Motor protector real-time acquisition main power supply circuit voltage, trigger corresponding port action under abnormal condition, cooperate with control circuit, realize two fans " one operation one spare " interlock conduction.The structure provides intuitive fault feedback, reduces maintenance cost, eliminates software logic failure or artificial misoperation risk, improves system security and reliability.

Description

Technical Field

[0001] This utility model relates to the field of motor power supply control technology, specifically a wiring structure for a motor protector of a dilution fan in a thermal power plant. Background Technology

[0002] In the flue gas denitrification system of thermal power plants, dilution fans are key equipment for ensuring the stable operation of the denitrification process. Their main function is to introduce air into the system to dilute reducing agents such as ammonia, ensuring thorough mixing with the flue gas, thereby efficiently removing nitrogen oxides and meeting environmental emission standards. Therefore, the stable operation of dilution fans is directly related to the power plant's environmental compliance and the safe power generation of the units.

[0003] If the dilution fan suddenly fails and stops operating, the dilution of the reducing agent will be interrupted, and the concentration of nitrogen oxides in the flue gas will rapidly exceed the standard. This will not only pose a risk of environmental penalties, but may also trigger the unit's protection shutdown, causing significant economic losses and unstable power supply.

[0004] To mitigate the aforementioned risks, thermal power plants generally adopt a "one-operated, one-standby" design, which involves configuring an operating dilution fan and a standby dilution fan. This is intended to allow for rapid replacement of the main dilution fan in the event of a main fan failure, thus maintaining the operation of the flue gas denitrification system. However, the current switching process for dilution fans still relies on manual operation, which has significant shortcomings: It lacks real-time monitoring and fault diagnosis capabilities for the main dilution fan's operating status, and cannot automatically activate the standby fan when the main dilution fan fails, resulting in a delayed switching response and affecting the stability of the flue gas denitrification system. Furthermore, manual operation is prone to errors, such as activating the standby dilution fan before the main fan has completely stopped, or having both fans operating simultaneously, potentially leading to electrical system overload, equipment damage, or even denitrification system shutdown.

[0005] Therefore, how to improve the control method of manually switching the "one in operation and one on standby" dilution fan to improve the fan switching response speed, reduce the risk of misoperation, and ensure the continuous and stable operation of the denitrification system is an urgent problem to be solved by those skilled in the art. Utility Model Content

[0006] To overcome the problems existing in related technologies, this utility model provides a wiring structure for a motor protector of a dilution fan in a thermal power plant. By optimizing the circuit structure of the dilution fan and introducing a motor protector, the main dilution fan can be automatically detected and switched, ensuring that the main dilution fan and the standby dilution fan never operate simultaneously, thus guaranteeing the continuous and stable operation of the denitrification system.

[0007] The technical solution adopted by this utility model is: a wiring structure for a dilution fan motor protector, including: a main power supply circuit and a control circuit;

[0008] The main power supply circuit includes a power supply, a circuit breaker, a first contactor, a second contactor, a first dilution fan, and a second dilution fan. The power supply is connected to the input port of the circuit breaker, and the output port of the circuit breaker is connected to the main contact input ports of the first and second contactors respectively. The main contact output port of the first contactor is connected to the first dilution fan, and the main contact output port of the second contactor is connected to the second dilution fan.

[0009] The control circuit includes a dilution fan selection circuit, a fan reset control circuit, and a motor protector. The motor protector includes a voltage signal input port, a normally open contact port, a normally closed contact port, and a control input port. The normally open contact port includes a first normally open contact and a second normally open contact. The normally closed contact port includes a first normally closed contact and a second normally closed contact.

[0010] The voltage signal input port is connected to the circuit breaker output port. The normally open contact of the first motor protector is connected to the positive terminal of the power supply. The normally open contact of the second motor protector is connected to the normally closed contact of the first motor protector. The normally closed contact of the second motor protector is connected to one end of the dilution fan selection circuit. The other end of the dilution fan selection circuit is connected to the negative terminal of the power supply. The control input port is connected to the fan reset control circuit.

[0011] Furthermore, the dilution fan selection circuit includes a first dilution fan start circuit, a second dilution fan start circuit, a first relay, and a second relay;

[0012] The first dilution fan starting circuit is connected in series with the first relay coil, the first contactor coil, and the normally closed contact of the second relay. One end of the first relay coil is connected to the normally closed contact of the second motor protector, and one end of the normally closed contact of the second relay is connected to the negative terminal of the power supply.

[0013] The second dilution fan starting circuit has a second normally open contact of a relay and a second contactor coil connected in series. One end of the normally open contact of the second relay is connected to the normally closed contact of the second motor protector, and one end of the second contactor coil is connected to the negative terminal of the power supply.

[0014] Furthermore, the fan reset control circuit includes a fan reset execution circuit and a third relay;

[0015] The fan reset execution circuit is connected in series with the first normally closed contact of the relay, the second relay coil, and the third relay coil. One end of the first normally closed contact is connected to the positive terminal of the power supply through a wire connected in series with the first switch, and is also connected to the DCS system signal through a signal line. One end of the third relay coil is connected to the control input port.

[0016] Furthermore, the fan reset control circuit also includes a fan reset self-holding circuit, in which a second switch and a normally open contact of the third relay are connected in series. One end of the second switch is connected to the positive terminal of the power supply, and one end of the normally open contact of the third relay is connected to the circuit between the coil of the second relay and the normally closed contact of the first relay.

[0017] Furthermore, the control input ports include a closing command input port, a tripping command input port, a reset command input port, and a device fault alarm port;

[0018] The closing command input port is connected to the DCS system signal via a signal line, and the closing command input port is connected to the positive terminal of the power supply via a wire with a fourth switch connected in series.

[0019] The trip command input port is connected to the DCS system signal via a signal line, and the trip command input port is connected to the positive terminal of the power supply via a wire with a third switch connected in series.

[0020] The reset command input port is connected to the fan reset control circuit.

[0021] The device fault alarm port is a normally open port, and the device fault alarm port is connected to the DCS system signal.

[0022] Furthermore, the motor protector is also equipped with an operation display unit interface, which is connected to a touch screen.

[0023] Furthermore, the power supply is a three-phase four-wire power supply, including phase line L1, phase line L2, phase line L3 and neutral line N, and the circuit breaker input port includes a first circuit breaker input contact, a second circuit breaker input contact and a third circuit breaker input contact.

[0024] The L1 phase line is connected to the input contact of the first circuit breaker, the L2 phase line is connected to the input contact of the second circuit breaker, and the L3 phase line is connected to the input contact of the third circuit breaker.

[0025] Furthermore, the circuit breaker output port includes a first circuit breaker output contact, a second circuit breaker output contact, and a third circuit breaker output contact;

[0026] The voltage signal input ports include a Ua port, a Ub port, a Uc port, and an Un port. The Ua port is connected to the output contact of the first circuit breaker, the Ub port is connected to the output contact of the second circuit breaker, the Uc port is connected to the output contact of the third circuit breaker, and the Un port is connected to the N neutral line.

[0027] The wiring structure of this utility model for a dilution fan motor protector has the following technical effects: (I) By setting up a motor protector, the voltage signal input port of the motor protector is connected to the output port of the circuit breaker, allowing for real-time acquisition of voltage parameters from the main power supply circuit, and full-process monitoring of the dilution fan's operating status. The motor protector can detect abnormal conditions such as overvoltage, undervoltage, and overload in the main power supply circuit of the dilution fan, and trigger the corresponding equipment port actions. Relying on the inherent equipment functions of the motor protector, not only is precise protection of the dilution fan achieved, but also intuitive fault status feedback is provided to operators, facilitating rapid problem location and repair, and reducing equipment maintenance costs.

[0028] (II) A wiring structure for the dilution fan selection circuit and the fan reset control circuit was constructed. The dilution fan selection circuit is connected to the normally closed contact of the second motor protector and the negative terminal of the power supply. The fan reset control circuit is connected to the control input port. Through a pure circuit structure design, and by utilizing the switching of the corresponding ports of the motor protector and the mutual cooperation between the dilution fan selection circuit and the fan reset control circuit, the first and second dilution fans are interlocked and single-conduction in a "one-operation-one-standby" manner at the hardware level. This pure hardware-based interlocking mechanism fundamentally eliminates the risk of simultaneous startup of the two fans due to software logic failure or human error, and substantially improves the system's safety level and operational reliability.

[0029] Other features and advantages disclosed in this utility model will be described in detail in the following detailed description section. Attached Figure Description

[0030] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0031] Figure 1 This is an overall schematic diagram of the wiring structure of a dilution fan motor protector according to an exemplary embodiment.

[0032] Figure reference numerals: 10. Power supply; 11. L1 phase line; 12. L2 phase line; 13. L3 phase line; 14. N neutral line; 20. Circuit breaker; 31. Main contact of the first contactor; 32. First contactor coil; 41. Main contact of the second contactor; 42. Second contactor coil; 50. First dilution fan; 51. Second dilution fan; 60. Motor protector; 61. Voltage signal input port; 611. Ua port; 612. Ub port; 613. Uc port; 614. Un port; 62. Normally open contact port of the motor protector; 621. Normally open contact of the first motor protector; 622. Normally open contact of the second motor protector; 63. Normally closed contact port of the motor protector. ; 631, Normally closed contact of the first motor protector; 632, Normally closed contact of the second motor protector; 641, Closing command input port; 642, Tripping command input port; 643, Reset command input port; 644, Device fault alarm port; 65, Operation display unit interface; 66, Touch screen; 71, Normally closed contact of the first relay; 72, First relay coil; 81, Normally closed contact of the second relay; 82, Normally open contact of the second relay; 83, Second relay coil; 91, Normally open contact of the third relay; 92, Third relay coil; 100, DCS system; 110, First switch; 111, Second switch; 112, Third switch; 113, Fourth switch. Detailed Implementation

[0033] The specific embodiments disclosed herein will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this disclosure.

[0034] like Figure 1 The diagram shows a disclosed exemplary embodiment of the present invention. The wiring structure of the dilution fan motor protector 60 of the present invention includes: a main power supply circuit and a control circuit. The main power supply circuit includes a power supply 10, a circuit breaker 20, a first contactor, a second contactor, a first dilution fan 50, and a second dilution fan 51. The power supply 10 is connected to the input port of the circuit breaker 20. The output port of the circuit breaker 20 is connected to the input ports of the main contacts 31 and 41 of the first and second contactors, respectively. The output port of the main contacts 31 of the first contactor is connected to the first dilution fan 50, and the output port of the main contacts 41 of the second contactor is connected to the second dilution fan 51.

[0035] The control circuit includes a dilution fan selection circuit, a fan reset control circuit, and a motor protector 60. The motor protector 60 includes a voltage signal input port 61, a normally open contact port 62, a normally closed contact port 63, and a control input port. The normally open contact port 62 includes a first normally open contact 621 and a second normally open contact 622. The normally closed contact port 63 includes a first normally closed contact 631 and a second normally closed contact 632.

[0036] The voltage signal input port 61 is connected to the output port of the circuit breaker 20. The normally open contact 621 of the first motor protector is connected to the positive terminal of the power supply 10. The normally open contact 622 of the second motor protector is connected to the normally closed contact 631 of the first motor protector. The normally closed contact 632 of the second motor protector is connected to one end of the dilution fan selection circuit. The other end of the dilution fan selection circuit is connected to the negative terminal of the power supply 10. The control input port is connected to the fan reset control circuit.

[0037] The wiring structure of this utility model's dilution fan motor protector 60 includes a main power supply circuit and a control circuit. In the main power supply circuit, the power supply 10 is connected to a first contactor and a second contactor via a circuit breaker 20. The first contactor is connected to the first dilution fan 50, and the second contactor is connected to the second dilution fan 51. The circuit breaker 20 in the main power supply circuit provides overload and short-circuit protection, ensuring basic electrical safety for the entire system. The first and second contactors, by controlling the opening and closing of the main contacts 31 and 41 of the first and second contactors, enable independent power supply switching between the first and second dilution fans 50 and 51, meeting the "one in operation, one standby" operation mode requirements.

[0038] In the control circuit, a motor protector 60 is provided. The motor protector 60 is an electrical device specifically designed to protect electric motors. Its core function is to monitor the operating parameters of the motor in real time to prevent equipment damage or safety hazards caused by faults. In the exemplary embodiment of this disclosure, the motor protector 60 can detect the voltage parameters of the main power supply circuit in real time, and when abnormal conditions such as motor overload, undervoltage, or overvoltage are detected, it quickly triggers the protection mechanism, causing the corresponding port to perform protection actions, thereby ensuring the safe and reliable operation of the system. In the exemplary embodiment of this disclosure, a dilution fan selection circuit and a fan reset control circuit are constructed. The dilution fan selection circuit is connected to the normally closed contact 632 of the second motor protector and the negative terminal of the power supply 10. The fan reset control circuit is connected to the control input port. Through a pure circuit structure design, by means of the on / off switching of the corresponding port of the motor protector 60 and the mutual cooperation between the dilution fan selection circuit and the fan reset control circuit, the first dilution fan 50 and the second dilution fan 51 are realized at the hardware level in an interlocked single conduction manner with "one in operation and one on standby". This hardware-based interlocking mechanism fundamentally eliminates the risk of two wind turbines starting simultaneously due to software logic failure or human error, thus substantially improving the system's safety level and operational reliability.

[0039] Specifically, such as Figure 1 As shown, in an exemplary embodiment of this disclosure, the dilution fan selection circuit includes a first dilution fan 50 start circuit, a second dilution fan 51 start circuit, a first relay, and a second relay;

[0040] The starting circuit of the first dilution fan 50 is connected in series with the first relay coil 72, the first contactor coil 32 and the second relay normally closed contact 81. One end of the first relay coil 72 is connected to the normally closed contact 632 of the second motor protector, and one end of the second relay normally closed contact 81 is connected to the negative terminal of the power supply 10.

[0041] The starting circuit of the second dilution fan 51 is connected in series with the normally open contact 82 of the second relay and the coil 42 of the second contactor. One end of the normally open contact 82 of the second relay is connected to the normally closed contact 632 of the second motor protector, and one end of the coil 42 of the second contactor is connected to the negative terminal of the power supply 10.

[0042] The fan reset control circuit includes a fan reset execution circuit and a third relay. The fan reset execution circuit has a first relay normally closed contact 71, a second relay coil 83, and a third relay coil 92 connected in series. One end of the first relay normally closed contact 71 is connected to the positive terminal of the power supply 10 through a wire connected in series with the first switch 110, and is also connected to the DCS system 100 signal through a signal line. One end of the third relay coil 92 is connected to the control input port.

[0043] The fan reset control circuit also includes a fan reset self-holding circuit. The fan reset self-holding circuit has a second switch 111 and a third relay normally open contact 91 connected in series. One end of the second switch 111 is connected to the positive terminal of the power supply 10, and one end of the third relay normally open contact 91 is connected to the circuit between the second relay coil 83 and the first relay normally closed contact 71.

[0044] In an exemplary embodiment of this disclosure, when the motor protector 60 is operating normally, it receives a closing command, and the normally open contacts 621 and 622 of the first and second motor protectors close, making the normally open contact port 62 of the motor protector conductive. At this time, current flows from the positive terminal of the power supply 10 to the normally open contacts 621, 622, 631, and 632 of the first and second motor protectors, flowing into the starting circuit of the first dilution fan 50. It then passes sequentially through the first relay coil 72, the first contactor coil 32, and the normally closed contact 81 of the second relay to the negative terminal of the power supply 10, energizing the first relay coil 72 and the first contactor coil 32. The main contact 31 of the first contactor closes, and the first dilution fan 50 starts. Simultaneously, when the first relay coil 72 is energized, the normally closed contact 71 of the first relay opens, cutting off the power supply path to the second relay coil 83 in the fan reset execution circuit. When the second relay coil 83 is de-energized, its normally closed contact is closed, and its normally open contact is open. This achieves interlocking between the starting circuit of the first dilution fan 50 and the starting circuit of the second dilution fan 51.

[0045] When the motor protector 60 detects a fault in the first dilution fan 50, its normally closed contact port 63 will trip, meaning the normally closed contact 631 of the first motor protector and the normally closed contact 632 of the second motor protector will disconnect. At this time, the starting circuit of the first dilution fan 50 is broken, the coil 72 of the first relay is de-energized, the normally closed contact 71 of the first relay closes, the coil 32 of the first contactor is de-energized, the main contact 31 of the first contactor opens, and the first dilution fan 50 is disconnected from the main power supply circuit.

[0046] When the first switch 110 is pressed or a reset signal is generated by the DCS system 100, current flows through the normally closed contact 71 of the first relay, the coil 83 of the second relay, and the coil 92 of the third relay to the control input port of the motor protector, and then flows into the negative terminal of the power supply 10 through the COM port of the motor protector. At this time, the coils 83 and 92 of the second relay are energized, and the normally closed contacts 631 and 632 of the first and second motor protectors reclose. The normally closed contact 81 of the second relay opens, cutting off the power supply to the starting circuit of the first dilution fan 50. At this time, the coil 32 of the first contactor remains de-energized, and the main contact 31 of the first contactor remains open. The normally open contact 82 of the second relay closes, and current flows from the normally closed contact 632 of the second motor protector through the normally open contact 82 of the second relay and the coil 42 of the second contactor to the negative terminal of the power supply 10. The main contact 41 of the second contactor closes, and the second dilution fan 51 starts. At the same time, the normally open contact 91 of the third relay closes, forming a fan reset self-holding circuit with the second switch 111, maintaining the reset state.

[0047] When the first dilution fan 50 is repaired and wants to be put back into use, the second switch 111 can be pressed. The second switch 111 is a normally closed switch. When the second switch 111 is pressed, it will disconnect the fan reset self-holding circuit, causing the second relay coil 83 and the third relay coil 92 to be de-energized. At this time, the normally open contact 82 of the second relay opens, and the normally closed contact 81 of the second relay closes. The starting circuit of the first dilution fan 50 is connected, the first contactor coil 32 is energized, the main contact 31 of the first contactor closes, and the first dilution fan 50 starts. The starting circuit of the second dilution fan 51 is disconnected, the second contactor coil 42 is de-energized, the main contact 41 of the second contactor opens, and the second dilution fan 51 stops.

[0048] For example, such as Figure 1 As shown in the exemplary embodiment of this disclosure, the motor protector control input port includes a closing command input port 641, a tripping command input port 642, a reset command input port 643, and a device fault alarm port 644. The closing command input port 641 is connected to the DCS system 100 via a signal line, and is also connected to the positive terminal of the power supply 10 via a wire connected in series with a fourth switch 113. The tripping command input port 642 is connected to the DCS system 100 via a signal line, and is also connected to the positive terminal of the power supply 10 via a wire connected in series with a third switch 112. The reset command input port 643 is connected to the fan reset control circuit. The device fault alarm port 644 is a normally open port, and is connected to the DCS system 100 via a signal line. The motor protector 60 also includes an operation display unit interface 65, which is connected to a touch screen 66.

[0049] The closing command input port 641 and the tripping command input port 642 are connected to the DCS system 100 via signal lines to enable remote control of the DCS system 100. Simultaneously, the closing command input port 641 is connected to the positive terminal of the power supply 10 via a wire connected in series with the fourth switch 113, and the tripping command input port 642 is connected to the positive terminal of the power supply 10 via a wire connected in series with the third switch 112, enabling manual control on-site.

[0050] When the DCS system 100 sends a closing signal, or the fourth switch 113 is closed, current flows into the closing command input port 641. After receiving the current signal, the motor protector 60's normally open contact port 62 is activated, and the first motor protector's normally open contact 621 and the second motor protector's normally open contact 622 close.

[0051] When the DCS system 100 sends a trip signal, or the third switch 112 is closed, current flows into the trip command input port 642. After receiving the current signal, the motor protector 60 will be activated again by the normally open contact port 62, and the normally open contact 621 of the first motor protector and the normally open contact 622 of the second motor protector will be disconnected.

[0052] The reset command input port 643 is connected to the wind turbine reset control circuit. Its specific functions are as described above and will not be repeated here.

[0053] The device fault alarm port 644 is a normally open port and is connected to the DCS system 100 for signal transmission. When the motor protector 60 detects an abnormal motor condition, in addition to triggering the normally closed contact port 63 of the motor protector to open the first normally closed contact 631 and the second normally closed contact 632 of the motor protector, it will also close the device fault alarm port 644 to send a fault signal to the DCS system 100.

[0054] The motor protector 60 is also equipped with an operation display unit interface 65, which is connected to the touch screen 66; it can display key parameters and fault information of the motor protector 60 and the motor in real time.

[0055] For example, such as Figure 1 As shown in the exemplary embodiment of this disclosure, the power supply 10 is a three-phase four-wire power supply 10, including L1 phase line 11, L2 phase line 12, L3 phase line 13 and N neutral line 14. The circuit breaker 20 input port includes a first circuit breaker 20 input contact, a second circuit breaker 20 input contact and a third circuit breaker 20 input contact. L1 phase line 11 is connected to the first circuit breaker 20 input contact, L2 phase line 12 is connected to the second circuit breaker 20 input contact, and L3 phase line 13 is connected to the third circuit breaker 20 input contact.

[0056] The output ports of circuit breaker 20 include a first output contact, a second output contact, and a third output contact. The voltage signal input port 61 includes port Ua 611, port Ub 612, port Uc 613, and port Un 614. Port Ua 611 is connected to the first output contact of circuit breaker 20, port Ub 612 is connected to the second output contact of circuit breaker 20, port Uc 613 is connected to the third output contact of circuit breaker 20, and port Un 614 is connected to the neutral line 14.

[0057] In the exemplary embodiments of this disclosure, the power supply 10 adopts a three-phase four-wire system. The circuit breaker 20, the main contacts 31 of the first contactor, the main contacts 41 of the second contactor, the first dilution fan 50, and the second dilution fan 51 are each provided with corresponding contacts or ports, which are connected one-to-one with the three phases of the power supply 10. The three-phase four-wire power supply 10 can provide a more stable power output. Compared with the single-phase power supply 10, it can transmit more power with the same conductor cross-sectional area, which is suitable for high-power motor loads and reduces line losses. By independently connecting the three phase lines, the load of the dilution fan can be evenly distributed to the three-phase power supply 10, avoiding the imbalance problem of the power supply 10 caused by excessive single-phase load and reducing the risk of grid fluctuations. The three input contacts and three output contacts of the contactor main contacts close / open synchronously, ensuring that the three-phase windings of the dilution fan are energized / de-energized simultaneously, avoiding the starting torque imbalance or operating vibration caused by phase inconsistency, ensuring the smooth and efficient operation of the dilution fan, and forming a fault linkage protection.

[0058] In an exemplary embodiment of this disclosure, the motor protector voltage signal input port 61 includes port Ua 611, port Ub 612, port Uc 613, and port Un 614, enabling comprehensive sampling of the line voltage and phase voltage of a three-phase four-wire circuit. It allows for real-time acquisition of the amplitude, phase, and waveform differences of each phase voltage, providing data support for accurate location of subsequent faults such as voltage imbalance, phase loss, and overvoltage / undervoltage. Power is drawn from the output contacts of the circuit breaker 20, utilizing the overload protection characteristics of the circuit breaker 20 to prevent hardware damage due to overcurrent or overvoltage when the voltage signal input port 61 is directly connected to the power grid.

[0059] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0060] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0061] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A dilution air fan motor protector wiring configuration, characterized by, include: Main power supply circuit and control circuit; The main power supply circuit includes a power supply, a circuit breaker, a first contactor, a second contactor, a first dilution fan, and a second dilution fan. The power supply is connected to the input port of the circuit breaker, and the output port of the circuit breaker is connected to the main contact input ports of the first and second contactors respectively. The main contact output port of the first contactor is connected to the first dilution fan, and the main contact output port of the second contactor is connected to the second dilution fan. The control circuit includes a dilution fan selection circuit, a fan reset control circuit, and a motor protector. The motor protector includes a voltage signal input port, a normally open contact port, a normally closed contact port, and a control input port. The normally open contact port includes a first normally open contact and a second normally open contact. The normally closed contact port includes a first normally closed contact and a second normally closed contact. The voltage signal input port is connected to the circuit breaker output port. The normally open contact of the first motor protector is connected to the positive terminal of the power supply. The normally open contact of the second motor protector is connected to the normally closed contact of the first motor protector. The normally closed contact of the second motor protector is connected to one end of the dilution fan selection circuit. The other end of the dilution fan selection circuit is connected to the negative terminal of the power supply. The control input port is connected to the fan reset control circuit.

2. The dilution air fan motor protector wiring configuration of claim 1, wherein, The dilution fan selection circuit includes a first dilution fan start circuit, a second dilution fan start circuit, a first relay, and a second relay; The first dilution fan starting circuit is connected in series with the first relay coil, the first contactor coil, and the normally closed contact of the second relay. One end of the first relay coil is connected to the normally closed contact of the second motor protector, and one end of the normally closed contact of the second relay is connected to the negative terminal of the power supply. The second dilution fan starting circuit has a second normally open contact of a relay and a second contactor coil connected in series. One end of the normally open contact of the second relay is connected to the normally closed contact of the second motor protector, and one end of the second contactor coil is connected to the negative terminal of the power supply.

3. The wiring structure of the dilution fan motor protector according to claim 2, characterized in that, The fan reset control circuit includes a fan reset execution circuit and a third relay; The fan reset execution circuit is connected in series with the first normally closed contact of the relay, the second relay coil, and the third relay coil. One end of the first normally closed contact is connected to the positive terminal of the power supply through a wire connected in series with the first switch, and is also connected to the DCS system signal through a signal line. One end of the third relay coil is connected to the control input port.

4. The dilution air fan motor protector wiring configuration of claim 3, wherein, The fan reset control circuit also includes a fan reset self-holding circuit. The fan reset self-holding circuit has a second switch and the normally open contact of the third relay connected in series. One end of the second switch is connected to the positive terminal of the power supply, and one end of the normally open contact of the third relay is connected to the circuit between the coil of the second relay and the normally closed contact of the first relay.

5. The dilution air fan motor protector wiring configuration of claim 1, wherein, The control input ports include a closing command input port, a tripping command input port, a reset command input port, and a device fault alarm port; The closing command input port is connected to the DCS system signal via a signal line, and the closing command input port is connected to the positive terminal of the power supply via a wire with a fourth switch connected in series. The trip command input port is connected to the DCS system signal via a signal line, and the trip command input port is connected to the positive terminal of the power supply via a wire with a third switch connected in series. The reset command input port is connected to the fan reset control circuit. The device fault alarm port is a normally open port, and the device fault alarm port is connected to the DCS system signal.

6. The wiring structure of the dilution fan motor protector according to claim 1, characterized in that, The motor protector is also equipped with an operation display unit interface, which is connected to a touch screen.

7. The dilution air fan motor protector wiring configuration of claim 1, wherein, The power supply is a three-phase four-wire power supply, including phase line L1, phase line L2, phase line L3 and neutral line N. The circuit breaker input port includes a first circuit breaker input contact, a second circuit breaker input contact and a third circuit breaker input contact. The L1 phase line is connected to the input contact of the first circuit breaker, the L2 phase line is connected to the input contact of the second circuit breaker, and the L3 phase line is connected to the input contact of the third circuit breaker.

8. The wiring structure of the dilution fan motor protector according to claim 7, characterized in that, The circuit breaker output port includes a first circuit breaker output contact, a second circuit breaker output contact, and a third circuit breaker output contact; The voltage signal input ports include a Ua port, a Ub port, a Uc port, and an Un port. The Ua port is connected to the output contact of the first circuit breaker, the Ub port is connected to the output contact of the second circuit breaker, the Uc port is connected to the output contact of the third circuit breaker, and the Un port is connected to the N neutral line.

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