Open-phase protection circuit, control method thereof and air conditioner control system
By setting up a control loop module in the three-phase line, the problem of communication being affected by power outage when a phase is missing in the three-phase line is solved, and communication stability and system reliability are achieved under phase loss conditions.
Patent Information
- Application Number
- CN202511763273.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-27
- Publication Date
- 2026-02-13
AI Technical Summary
In the existing technology, when a phase is lost in a three-phase line, the phase sequence protector causes the equipment connected to the three-phase line to lose power, affecting the communication of the control system and causing the system to be unstable.
A control circuit module is set up in the three-phase line. When a phase is lost, the control circuit module controls the line that is not lost to supply power to the auxiliary control module and disconnects the connection between the main circuit module and the motor, thus avoiding the need to use an additional phase sequence protector.
It enables the auxiliary control module to maintain power supply in the event of a phase loss, ensuring communication stability with the control system and improving the operational reliability of the control system.
Smart Images
Figure CN121529446A_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present invention relate to the field of electronic technology, and in particular to a phase loss protection circuit and its control method and an air conditioning control system. Background Technology
[0002] In a three-phase power line, a phase loss can potentially damage equipment connected to the three-phase line. Current technology typically equips power supply lines with phase sequence protectors to prevent damage caused by phase loss. However, when providing phase loss protection, the phase sequence protector de-energizes equipment connected to the three-phase line, but this also de-energizes other modules, affecting communication with the control system and hindering its operation. Summary of the Invention
[0003] This invention provides a phase loss protection circuit and its control method, as well as an air conditioning control system, to maintain communication between other modules and the control system during phase loss protection.
[0004] According to one aspect of the present invention, a phase loss protection circuit is provided, comprising:
[0005] Three-phase power input module;
[0006] The main circuit module has its input terminal connected to the three-phase power input module via a three-phase line, and its output terminal connected to the motor.
[0007] The system includes a control loop module and an auxiliary control module. The control loop module is connected to the power supply terminal of the three-phase line and the auxiliary control module, respectively. The communication terminal of the auxiliary control module is connected to the control system. The control loop module is used to control one of the three-phase lines that is not missing to supply power to the auxiliary control module when one phase of the three-phase line is missing, and to control the main circuit module to disconnect from the motor.
[0008] Optionally, the control loop module includes a loop control unit, a first loop execution unit, a second loop execution unit, and a third loop execution unit; the power supply terminal of the auxiliary control module includes a first power supply terminal and a second power supply terminal; the three-phase line includes a first phase line, a second phase line, and a third phase line.
[0009] The first end of the first loop execution unit is connected to the first phase line, the second end of the first loop execution unit is connected to the first power supply end of the auxiliary control module, the first end of the second loop execution unit is connected to the second phase line, the second end of the second loop execution unit is connected to the first power supply end of the auxiliary control module, the first end of the third loop execution unit is connected to the third phase line, and the second end of the third loop execution unit is connected to the first power supply end of the auxiliary control module.
[0010] The first end of the loop control unit is connected to the first phase line, the second end of the loop control unit is connected to the second phase line, the third end of the loop control unit is connected to the third phase line, the fourth end of the loop control unit is connected to the second power supply end of the auxiliary control module, and the second power supply end of the auxiliary control module is connected to the neutral line; the loop control unit is used to control the first loop execution unit, the second loop execution unit and the third loop execution unit to be turned on in connection with one of the non-phase line in response to the phase line.
[0011] Optionally, the control loop module comprises a first relay, a second relay and a third relay, the first relay comprises a first coil, a first normally open contact, a second normally open contact, a third normally open contact and a first normally closed contact, the second relay comprises a second coil, a fourth normally open contact, a fifth normally open contact, a sixth normally open contact and a second normally closed contact, and the third relay comprises a third coil, a seventh normally open contact, an eighth normally open contact, a ninth normally open contact and a third normally closed contact.
[0012] The loop control unit comprises the first coil, the second coil and the third coil, the first coil is connected between the first phase line and the second power supply end of the auxiliary control module, the second coil is connected between the second phase line and the second power supply end of the auxiliary control module, and the third coil is connected between the third phase line and the second power supply end of the auxiliary control module.
[0013] The first loop execution unit comprises a first loop and a second loop, the first loop comprises the first normally open contact, the fourth normally open contact and the seventh normally open contact connected in series between the first phase line and the first power supply end of the auxiliary control module, and the second loop comprises the second normally open contact, the fifth normally open contact and the third normally closed contact connected in series between the first phase line and the first power supply end of the auxiliary control module.
[0014] The second loop execution unit comprises a third loop, and the third loop comprises the first normally closed contact, the sixth normally open contact and the eighth normally open contact connected in series between the second phase line and the first power supply end of the auxiliary control module.
[0015] The third loop execution unit comprises a fourth loop comprising the third normally open contact, the second normally closed contact and the ninth normally open contact connected in series between the third phase line and the first power terminal of the auxiliary control module.
[0016] Optionally, the first relay further comprises a tenth normally open contact, the second relay further comprises a sixth normally closed contact, and the third relay further comprises an eighth normally closed contact.
[0017] The first loop execution unit further comprises a fifth loop comprising the tenth normally open contact, the sixth normally closed contact and the eighth normally closed contact connected in series between the first phase line and the first power terminal of the auxiliary control module.
[0018] Optionally, the first relay further comprises a fourth normally closed contact, the second relay further comprises an eleventh normally open contact, and the third relay further comprises a ninth normally closed contact.
[0019] The second loop execution unit further comprises a sixth loop comprising the fourth normally closed contact, the eleventh normally open contact and the ninth normally closed contact connected in series between the second phase line and the first power terminal of the auxiliary control module.
[0020] Optionally, the first relay further comprises a fifth normally closed contact, the second relay further comprises a seventh normally closed contact, and the third relay further comprises a twelfth normally open contact.
[0021] The third loop execution unit further comprises a seventh loop comprising the fifth normally closed contact, the seventh normally closed contact and the twelfth normally open contact connected in series between the third phase line and the first power terminal of the auxiliary control module.
[0022] Optionally, the first relay further comprises a thirteenth normally open contact, the second relay further comprises a fourteenth normally open contact, and the third relay further comprises a fifteenth normally open contact.
[0023] The open-phase protection circuit further comprises a fourth relay comprising a fourth coil and a sixteenth normally open contact corresponding to the first phase line, the second phase line and the third phase line; the fourth coil, the thirteenth normally open contact, the fourteenth normally open contact and the fifteenth normally open contact are connected in series between the first sub-terminal and the second sub-terminal of the output terminal of the auxiliary control module.
[0024] According to another aspect of the present application, there is provided a control method of a phase-loss protection circuit, the phase-loss protection circuit comprising a three-phase power input module, a main circuit module, a control circuit module and an auxiliary control module, an input end of the main circuit module being connected with the three-phase power input module through a three-phase line, an output end of the main circuit module being connected with a motor;
[0025] The control method of the phase-loss protection circuit comprises:
[0026] When a line in the three-phase line is in phase loss, the main circuit module is controlled to disconnect the connection with the motor by the control circuit module, and one phase line in the three-phase line which is not in phase loss is controlled to supply power to the auxiliary control module.
[0027] Optionally, the control circuit module comprises a circuit control unit, a first circuit execution unit, a second circuit execution unit and a third circuit execution unit; the first circuit execution unit comprises a first circuit, a second circuit and a fifth circuit, the second circuit execution unit comprises a third circuit and a sixth circuit, and the third circuit execution unit comprises a fourth circuit and a seventh circuit;
[0028] The control method of the phase-loss protection circuit comprises:
[0029] When a single-phase line in the three-phase line is in phase loss, the circuit control unit is controlled to supply power to the auxiliary control module by controlling one of two circuits connected with the non-phase-loss line in the second circuit, the third circuit and the fourth circuit to be turned on in response to the phase-loss line; wherein the two circuits connected with the non-phase-loss line are not turned on at the same time.
[0030] When two-phase lines in the three-phase line are in phase loss, the circuit control unit is controlled to supply power to the auxiliary control module by controlling one circuit connected with the non-phase-loss line in the fifth circuit, the sixth circuit and the seventh circuit to be turned on in response to the phase-loss line.
[0031] According to another aspect of the present application, there is provided an air conditioner control system, the air conditioner control system comprising the phase-loss protection circuit provided by any of the embodiments of the present application.
[0032] The technical scheme provided by the embodiment of the present application is that a control loop module is arranged between the three-phase line and the auxiliary control module, when a phase is missing in the three-phase line, one phase in the three-phase line which is not missing is controlled to supply power to the auxiliary control module, and the main loop module is controlled to disconnect the connection between the auxiliary control module and the motor. The circuit structure of the scheme is simple, and an additional phase sequence protector is not needed to realize the missing phase protection of the motor, and the power supply of the auxiliary control module used for communication with the control system can be maintained, which is beneficial to improving the communication stability of the control system and improving the working reliability of the system.
[0033] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present application, nor is it used to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS
[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.
[0035] Figure 1 A structural schematic diagram of a missing phase protection circuit provided by the embodiment of the present application is shown in the figure.
[0036] Figure 2 A structural schematic diagram of another missing phase protection circuit provided by the embodiment of the present application is shown in the figure.
[0037] Figure 3 A structural schematic diagram of another missing phase protection circuit provided by the embodiment of the present application is shown in the figure.
[0038] Figure 4 A structural schematic diagram of another missing phase protection circuit provided by the embodiment of the present application is shown in the figure.
[0039] Figure 5 A structural schematic diagram of another missing phase protection circuit provided by the embodiment of the present application is shown in the figure. DETAILED DESCRIPTION
[0040] In order to make the person skilled in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings of the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should be within the scope of protection of the present application.
[0041] It should be noted that the terms "first", "second", and the like in the description and in the claims of the present application and the above-described accompanying drawings are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.
[0042] Figure 1 A structural schematic diagram of a phase loss protection circuit provided for an embodiment of the present application is shown in Figure 1 The phase loss protection circuit provided in the embodiment includes:
[0043] a three-phase power input module 10;
[0044] a main circuit module 20, an input end of the main circuit module 20 being connected with the three-phase power input module 10 through a three-phase line, and an output end of the main circuit module 20 being connected with a motor 100;
[0045] a control circuit module 30 and an auxiliary control module 40, the control circuit module 30 being connected with the three-phase line and a power supply end PI of the auxiliary control module 40 respectively, a communication end CO of the auxiliary control module 40 being connected in communication with a control system, and the control circuit module 30 being used for controlling a phase line in a three-phase line that is not in phase loss to supply power to the auxiliary control module 40 and controlling the main circuit module 20 to disconnect the connection between the main circuit module 20 and the motor 100 when a line in the three-phase line is in phase loss.
[0046] Specifically, the main circuit module 20 inputs a three-phase power voltage through the three-phase line, and the three-phase power voltage is provided by the three-phase power input module 10. When all the three-phase lines are normal, the main circuit module 20 is turned on to normally supply power to the motor 100. Among them, the motor 100 can be different devices in different application scenarios. For example, in an air conditioner control system, the motor 100 can be a compressor. Among them, the main circuit module 20 can be controlled to be turned on and off by the control circuit module 30, and the main circuit module 20 and the control circuit module 30 can be directly connected or indirectly connected.
[0047] When a phase loss occurs in the three-phase line, the control loop module 30 can control the main loop module 20 to disconnect according to the phase loss information, thereby cutting off the power supply loop of the motor 100 and preventing damage to the motor. At the same time, the control module 30 can also control the power supply end PI of the auxiliary control module 40 to provide a power supply voltage according to the phase loss information, so that the auxiliary control module 40 can work normally, thereby ensuring that the auxiliary control module 40 and the control system can normally communicate. Here, the auxiliary control module 40 can be a module for processing sensor signals, performing logical operations and outputting corresponding control instructions, such as a PLC or other control unit. The auxiliary control module 40 includes a communication module to realize data interaction with the control system.
[0048] The technical scheme provided by the embodiment of the application sets the control loop module 30 between the three-phase line and the auxiliary control module 40, controls the power supply of the auxiliary control module 40 through a phase line that does not lose power in the three-phase line, and controls the main loop module 20 to disconnect from the motor 100. The circuit structure of the present scheme is simple, and an additional phase sequence protector is not required to realize phase loss protection of the motor 100 while maintaining the power supply of the auxiliary control module 40 for communication with the control system, which is conducive to improving the communication stability of the control system and improving the working reliability of the system.
[0049] Figure 2 Another structure diagram of a phase loss protection circuit provided by the embodiment of the application is shown in FIG. 4. Figure 2 On the basis of the above embodiment, the control loop module 30 can optionally include a loop control unit 310, a first loop execution unit 301, a second loop execution unit 302 and a third loop execution unit 303; the power supply end PI of the auxiliary control module 40 can include a first power supply end PI1 and a second power supply end PI2; the three-phase line can include a first phase line L1, a second phase line L2 and a third phase line L3; wherein the first power supply end PI1 of the auxiliary control module 40 can be used to input a single-phase voltage, and the second power supply end PI2 of the auxiliary control module 40 can be used to connect a neutral line.
[0050] The first end of the first loop execution unit 301 is connected to the first phase line L1, the second end of the first loop execution unit 301 is connected to the first power supply end PI1 of the auxiliary control module 40, the first end of the second loop execution unit 302 is connected to the second phase line L2, the second end of the second loop execution unit 302 is connected to the first power supply end PI1 of the auxiliary control module 40, the first end of the third loop execution unit 303 is connected to the third phase line L3, and the second end of the third loop execution unit 303 is connected to the first power supply end PI1 of the auxiliary control module 40.
[0051] The first end of the loop control unit 310 is connected to the first phase line L1, the second end of the loop control unit 310 is connected to the second phase line L2, the third end of the loop control unit 310 is connected to the third phase line L3, and the fourth end of the loop control unit 310 is connected to the second power supply end PI2 of the auxiliary control module 40, and the second power supply end PI2 of the auxiliary control module 40 is connected to the neutral line LN; the loop control unit 310 is used to control one of the first loop execution unit 301, the second loop execution unit 302 and the third loop execution unit 303 to be turned on in response to the phase loss line.
[0052] For example, if the first phase line L1 is phase loss, the second phase line L2 and the third phase line L3 are normal, then the loop control unit 310 responds to the phase loss information of the first phase line L1, controls the first loop execution unit 301 to disconnect the connection between the first phase line L1 and the first power supply end PI1 of the auxiliary control module 40, and controls the second loop execution unit 302 or the third loop execution unit 303 to be turned on, so that the second phase line L2 or the third phase line L3 provides the power supply voltage for the first power supply end PI1 of the auxiliary control module 40.
[0053] If the second phase line L2 is phase loss, the first phase line L1 and the third phase line L3 are normal, then the loop control unit 310 responds to the phase loss information of the second phase line L2, controls the second loop execution unit 302 to disconnect the connection between the second phase line L2 and the first power supply end PI1 of the auxiliary control module 40, and controls the first loop execution unit 301 or the third loop execution unit 303 to be turned on, so that the first phase line L1 or the third phase line L3 provides the power supply voltage for the first power supply end PI1 of the auxiliary control module 40.
[0054] If the third phase line L3 is phase loss, the first phase line L1 and the second phase line L2 are normal, then the loop control unit 310 responds to the phase loss information of the third phase line L3, controls the third loop execution unit 303 to disconnect the connection between the third phase line L3 and the first power supply end PI1 of the auxiliary control module 40, and controls the second loop execution unit 302 or the first loop execution unit 301 to be turned on, so that the second phase line L2 or the first phase line L1 provides the power supply voltage for the first power supply end PI1 of the auxiliary control module 40.
[0055] Optionally, when all three phase lines are normal, one of the first loop execution unit 301, the second loop execution unit 302 and the third loop execution unit 303 can provide the power supply voltage for the first power supply end PI1 of the auxiliary control module 40.
[0056] In an optional implementation of the embodiment, the loop control unit 310 can be composed of relays (e.g., composed of coils of relays, the coils are denoted by corresponding reference numerals), and each loop execution unit can be composed of contacts of the relays. Figure 3 Another structure diagram of the phase deficiency protection circuit is provided in the embodiment of the application, referring to Figure 3 On the basis of the above embodiment, optionally, the control loop module 30 comprises a first relay KA1, a second relay KA2 and a third relay KA3, the first relay KA1 comprises a first coil, a first normally open contact KA1.1, a second normally open contact KA1.3, a third normally open contact KA1.4 and a first normally closed contact KA1.6, the second relay KA2 comprises a second coil, a fourth normally open contact KA2.1, a fifth normally open contact KA2.3, a sixth normally open contact KA2.4 and a second normally closed contact KA2.6, and the third relay KA3 comprises a third coil, a seventh normally open contact KA3.1, an eighth normally open contact KA3.3, a ninth normally open contact KA3.4 and a third normally closed contact KA3.6.
[0057] The loop control unit 310 comprises a first coil, a second coil and a third coil, the first coil is connected between the first phase line L1 and the second power terminal PI2 of the auxiliary control module 40, the second coil is connected between the second phase line L2 and the second power terminal PI2 of the auxiliary control module 40, and the third coil is connected between the third phase line L3 and the second power terminal PI2 of the auxiliary control module 40.
[0058] The first loop execution unit 301 comprises a first loop 1# and a second loop 2#, the first loop 1# comprises the first normally open contact KA1.1, the fourth normally open contact KA2.1 and the seventh normally open contact KA3.1 connected in series between the first phase line L1 and the first power terminal PI1 of the auxiliary control module 40, and the second loop 2# comprises the second normally open contact KA1.3, the fifth normally open contact KA2.3 and the third normally closed contact KA3.6 connected in series between the first phase line L1 and the first power terminal PI1 of the auxiliary control module 40.
[0059] The second loop execution unit 302 comprises a third loop 3#, the third loop 3# comprises the first normally closed contact KA1.6, the sixth normally open contact KA2.4 and the eighth normally open contact KA3.3 connected in series between the second phase line L2 and the first power terminal PI1 of the auxiliary control module 40.
[0060] The third loop execution unit 303 comprises a fourth loop 4#, the fourth loop 4# comprises the third normally open contact KA1.4, the second normally closed contact KA2.6 and the ninth normally open contact KA3.4 connected in series between the third phase line L3 and the first power terminal PI1 of the auxiliary control module 40.
[0061] Specifically, when the first phase line L1 is out of phase, the second phase line L2 and the third phase line L3 are normal, the coil of the first relay KA1 loses power, the normally open contact of the first relay KA1 opens, the normally closed contact of the first relay KA1 closes, the coils of the second relay KA2 and the third relay KA3 obtain power, the corresponding normally open contacts thereof close, and the normally closed contacts open. Therefore, the first normally open contact KA1.1 in the first loop 1# opens, the second normally open contact KA1.3 in the second loop 2# opens, and the first loop 1# and the second loop 2# are disconnected. The first normally closed contact KA1.6 in the third loop 3# closes, the sixth normally open contact KA2.4 closes, and the eighth normally open contact KA3.3 closes, and the third loop 3# is turned on. The second normally closed contact KA2.6 in the fourth loop 4# opens, and the fourth loop 4# is disconnected. In summary, when the first phase line L1 is out of phase, the second phase line L2 and the third phase line L3 are normal, the third loop 3# supplies power to the auxiliary control module 40.
[0062] When the second phase line L2 is out of phase, the first phase line L1 and the third phase line L3 are normal, the coil of the second relay KA2 loses power, the normally open contact of the second relay KA2 opens, the normally closed contact of the second relay KA2 closes, the coils of the first relay KA1 and the third relay KA3 obtain power, the corresponding normally open contacts thereof close, and the normally closed contacts open. Therefore, the fourth normally open contact KA2.1 in the first loop 1# opens, the fifth normally open contact KA2.3 in the second loop 2# opens, and the first loop 1# and the second loop 2# are disconnected. The sixth normally open contact KA2.4 in the third loop 3# opens, and the third loop 3# is disconnected. The second normally closed contact KA2.6 in the fourth loop 4# closes, the third normally open contact KA1.4 and the ninth normally open contact KA3.4 close, and the fourth loop 4# is turned on. In summary, when the second phase line L2 is out of phase, the first phase line L1 and the third phase line L3 are normal, the fourth loop 4# supplies power to the auxiliary control module 40.
[0063] When the third phase line L3 is open phase, the first phase line L1 and the second phase line L2 are normal, the coil of the third relay KA3 loses power, the normally open contact of the third relay KA3 is opened, the normally closed contact of the third relay KA3 is closed, the coils of the first relay KA1 and the second relay KA2 are powered, the corresponding normally open contacts of the two are closed, and the normally closed contacts are opened. Therefore, the seventh normally open contact KA3.1 in the first loop 1# is opened, the first loop 1# is disconnected, the second normally open contact KA1.3 in the second loop 2# is closed, the fifth normally open contact KA2.3 is closed, and the third normally closed contact KA3.6 is closed, so that the second loop 2# is turned on. The eighth normally open contact KA3.3 in the third loop 3# is opened, and the third loop 3# is disconnected. The ninth normally open contact KA3.4 in the fourth loop 4# is opened, and the fourth loop 4# is disconnected. In summary, when the third phase line L3 is open phase, the first phase line L1 and the second phase line L2 are normal, and the second loop 2# supplies power to the auxiliary control module 40.
[0064] Optionally, the open phase of the three-phase line includes not only single-phase open phase, but also two-phase open phase. Figure 4 Another open phase protection circuit structure diagram is provided for the embodiment of the application, and the control logic when the two-phase open phase of the three-phase line occurs is specifically shown. Figure 4 On the basis of the above embodiment, optionally, the first relay KA1 further includes a tenth normally open contact KA1.5, the second relay KA2 further includes a sixth normally closed contact KA2.7, and the third relay KA3 further includes an eighth normally closed contact KA3.7.
[0065] The first loop execution unit 301 further includes a fifth loop 5#, and the fifth loop 5# includes the tenth normally open contact KA1.5, the sixth normally closed contact KA2.7, and the eighth normally closed contact KA3.7 connected in series between the first phase line L1 and the first power supply end PI1 of the auxiliary control module 40.
[0066] And / or, the first relay KA1 further includes a fourth normally closed contact KA1.7, the second relay KA2 further includes an eleventh normally open contact KA2.5, and the third relay KA3 further includes a ninth normally closed contact KA3.8.
[0067] The second loop execution unit 302 further includes a sixth loop 6#, and the sixth loop 6# includes the fourth normally closed contact KA1.7, the eleventh normally open contact KA2.5, and the ninth normally closed contact KA3.8 connected in series between the second phase line L2 and the first power supply end PI1 of the auxiliary control module 40.
[0068] And / or, the first relay KA1 further includes a fifth normally closed contact KA1.8, the second relay KA2 further includes a seventh normally closed contact KA2.8, and the third relay KA3 further includes a twelfth normally open contact KA3.5.
[0069] The third loop execution unit 303 further comprises a seventh loop 7# including a fifth normally closed contact KA1.8, a seventh normally closed contact KA2.8 and a twelfth normally open contact KA3.5 connected in series between the third phase line L3 and the first power terminal PI1 of the auxiliary control module 40.
[0070] In particular, when the first phase line LI and the second phase line L2 are out of phase and the third phase line L3 is normal, the normally open contacts of the first relay KA1 and the second relay KA2 are open, the normally closed contacts are closed, and the normally open contact of the third relay KA3 is closed, the normally closed contact is open. Therefore, the tenth normally open contact KA1.5 in the fifth loop 5# is open, the sixth normally closed contact KA2.7 is closed, and the eighth normally closed contact KA3.7 is open, and the fifth loop 5# is disconnected; the fourth normally closed contact KA1.7 in the sixth loop 6# is closed, the eleventh normally open contact KA2.5 is open, and the ninth normally closed contact KA3.8 is open, and the sixth loop 6# is disconnected; the fifth normally closed contact KA1.8 in the seventh loop 7# is closed, the seventh normally closed contact KA2.8 is closed, and the twelfth normally open contact KA3.5 is closed, and the seventh loop 7# is turned on. In summary, when the first phase line LI and the second phase line L2 are out of phase and the third phase line L3 is normal, the auxiliary control module 40 is powered by the seventh loop 7#.
[0071] When the first phase line LI and the third phase line L3 are out of phase and the second phase line L2 is normal, the normally open contacts of the first relay KA1 and the third relay KA3 are open, the normally closed contacts are closed, and the normally open contact of the second relay KA2 is closed, the normally closed contact is open. Therefore, the tenth normally open contact KA1.5 in the fifth loop 5# is open, the sixth normally closed contact KA2.7 is closed, and the eighth normally closed contact KA3.7 is open, and the fifth loop 5# is disconnected; the fourth normally closed contact KA1.7 in the sixth loop 6# is closed, the eleventh normally open contact KA2.5 is closed, and the ninth normally closed contact KA3.8 is closed, and the sixth loop 6# is turned on; the fifth normally closed contact KA1.8 in the seventh loop 7# is closed, the seventh normally closed contact KA2.8 is open, and the twelfth normally open contact KA3.5 is open, and the seventh loop 7# is disconnected. In summary, when the first phase line LI and the third phase line L3 are out of phase and the second phase line L2 is normal, the auxiliary control module 40 is powered by the sixth loop 6#.
[0072] When the second phase L2 and the third phase L3 are missing, and the first phase L1 is normal, the normally open contacts of the second relay KA2 and the third relay KA3 are open, and their normally closed contacts are closed. The normally open contact of the first relay KA1 is closed, and its normally closed contact is open. Therefore, in the fifth circuit 5#, the tenth normally open contact KA1.5 is closed, the sixth normally closed contact KA2.7 is closed, and the eighth normally closed contact KA3.7 is closed, making the fifth circuit 5# conductive. In the sixth circuit 6#, the fourth normally closed contact KA1.7 is open, the eleventh normally open contact KA2.5 is closed, and the ninth normally closed contact KA3.8 is closed, making the sixth circuit 6# disconnected. In the seventh circuit 7#, the fifth normally closed contact KA1.8 is open, the seventh normally closed contact KA2.8 is closed, and the twelfth normally open contact KA3.5 is open, making the seventh circuit 7# disconnected. In summary, when the second phase L2 and the third phase L3 are missing, and the first phase L1 is normal, the auxiliary control module 40 is powered by the fifth circuit 5#.
[0073] When a single phase loss occurs, since the fifth circuit 5#, the sixth circuit 6#, and the seventh circuit 7# are all equipped with normally closed contacts corresponding to relays connected to the lines without phase loss as interlocking, the fifth circuit 5#, the sixth circuit 6#, and the seventh circuit 7# will not conduct. Only one of the two circuits connected to the lines without phase loss will supply power to the auxiliary control module 40, thus preventing two phase lines from simultaneously supplying power to the first power supply terminal PI1 of the auxiliary control module 40, and ensuring the reliability of the power supply.
[0074] Optionally, when all three phases are normal, only the first circuit 1# is connected, and the first circuit 1# supplies power to the auxiliary control module 40.
[0075] The technical solution provided in this embodiment, through the combination logic of normally open and normally closed contacts of three relays, ensures that when any one or two phases of a three-phase circuit are missing, there is one and only one circuit that is conducting, thereby providing power to the auxiliary control module 40. This solution has a simple structure, which helps to reduce maintenance costs.
[0076] Figure 5 This is a schematic diagram of another phase loss protection circuit provided in an embodiment of the present invention, referred to... Figure 5 Based on the above embodiments, optionally, the first relay KA1 further includes a thirteenth normally open contact KA1.2, the second relay KA2 further includes a fourteenth normally open contact KA2.2, and the third relay KA3 further includes a fifteenth normally open contact KA3.2;
[0077] The phase loss protection circuit includes a fourth relay KM1, which comprises a fourth coil and a sixteenth normally open contact KM1.1. The sixteenth normally open contact KM1.1 is connected to the first phase line L1, the second phase line L2, and the third phase line L3. The fourth coil, the thirteenth normally open contact KA1.2, the fourteenth normally open contact KA2.2, and the fifteenth normally open contact KA3.2 are connected in series between the first and second sub-terminals of the output terminal of the auxiliary control module 40. Here, the sixteenth normally open contact KM1.1 of the fourth relay KM1 is located in the main circuit module 20.
[0078] When a phase is lost in the three-phase circuit, one or two of the thirteenth normally open contact KA1.2, the fourteenth normally open contact KA2.2, and the fifteenth normally open contact KA3.2 open, causing the coil of the fourth relay KM1 to lose power, thereby driving the sixteenth normally open contact KM1.1 to open, disconnecting the main circuit module 20 from the motor 100, thus achieving the purpose of protecting the motor 100.
[0079] Optionally, the first relay KA1, the second relay KA2 and the third relay KA3 are all intermediate relays, and the fourth relay KM1 is a contactor.
[0080] Optionally, the main circuit module 20 also includes a thermal overload relay OL, which automatically disconnects when the motor 100 is overloaded, protecting the motor 100 from overload burnout.
[0081] Optionally, the three-phase power input module 10 may be equipped with a circuit breaker for power switching, enabling manual on / off control of the circuit, and also providing short-circuit protection.
[0082] Optionally, the present invention also provides a control method for a phase loss protection circuit, such as... Figure 1 As shown, the phase loss protection circuit includes a three-phase power input module 10, a main circuit module 20, a control circuit module 30, and an auxiliary control module 40. The input terminal of the main circuit module 20 is connected to the three-phase power input module 10 through a three-phase line, and the output terminal of the main circuit module 20 is connected to the motor 100.
[0083] The control methods for phase loss protection circuits include:
[0084] When a phase is missing in a three-phase circuit, the main circuit module is disconnected from the motor by the control circuit module, and at the same time, one phase of the three-phase circuit that is not missing a phase is controlled to supply power to the auxiliary control module.
[0085] The technical solution provided by this invention, by setting up a control loop module 30 between the three-phase line and the auxiliary control module 40, controls one phase of the three-phase line that is not missing to supply power to the auxiliary control module 40 when a phase is lost, and controls the main loop module 20 to disconnect from the motor 100. This solution has a simple circuit structure and can achieve phase loss protection for the motor 100 without the need for an additional phase sequence protector, while also maintaining power supply to the auxiliary control module 40 used for communication with the control system. This improves the communication stability and operational reliability of the control system.
[0086] Optionally, the control method for the phase loss protection circuit provided in this embodiment includes:
[0087] When a single phase is lost in a three-phase circuit, the control circuit control unit responds to the lost phase by controlling one of the two circuits in the second, third, and fourth circuits that are connected to the unlost phase line to conduct, thereby supplying power to the auxiliary control module; however, the two circuits connected to the unlost phase line do not conduct simultaneously.
[0088] When two phases of a three-phase circuit are missing, the control circuit control unit responds by controlling one of the five, six, or seven circuits connected to the non-missing phases to conduct, thereby supplying power to the auxiliary control module.
[0089] The specific working process / principle of this control method can be referred to the relevant descriptions in the above embodiments. This control method also has the beneficial effects described in the above embodiments, and will not be repeated here.
[0090] Optionally, the present invention also provides an air conditioning control system, which includes the phase loss protection circuit provided in any embodiment of the present invention. Therefore, the air conditioning control system also has the beneficial effects described in the above embodiments, and will not be repeated here.
[0091] Optionally, the air conditioning control system provided in this embodiment may include a deep dehumidification mode. During the operation of the air conditioning control system, core high-power components such as compressors and fans that rely heavily on three-phase power supply are often involved. A single phase loss during operation can lead to a series of problems, including component damage and system failure. During deep dehumidification, the equipment is often operating under high load, amplifying the hazards of a single phase loss. In deep dehumidification mode, the single phase loss protection circuit provided in this embodiment can prevent compressor damage and maintain communication with the control system, thus ensuring the stability of the control system.
[0092] Of course, in other embodiments, it can also be used in other working modes, not limited to the deep dehumidification mode, and this embodiment does not limit it in this regard.
[0093] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.
[0094] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.
Claims
1. A phase loss protection circuit, characterized in that, include: Three-phase power input module; The main circuit module has its input terminal connected to the three-phase power input module via a three-phase line, and its output terminal connected to the motor. The system includes a control loop module and an auxiliary control module. The control loop module is connected to the power supply terminal of the three-phase line and the auxiliary control module, respectively. The communication terminal of the auxiliary control module is connected to the control system. The control loop module is used to control one of the three-phase lines that is not missing to supply power to the auxiliary control module when one phase of the three-phase line is missing, and to control the main circuit module to disconnect from the motor.
2. The phase loss protection circuit according to claim 1, characterized in that, The control loop module includes a loop control unit, a first loop execution unit, a second loop execution unit, and a third loop execution unit; the power supply terminals of the auxiliary control module include a first power supply terminal and a second power supply terminal; the three-phase line includes a first-phase line, a second-phase line, and a third-phase line. The first end of the first loop execution unit is connected to the first phase line, the second end of the first loop execution unit is connected to the first power supply terminal of the auxiliary control module, the first end of the second loop execution unit is connected to the second phase line, the second end of the second loop execution unit is connected to the first power supply terminal of the auxiliary control module, the first end of the third loop execution unit is connected to the third phase line, and the second end of the third loop execution unit is connected to the first power supply terminal of the auxiliary control module. The first terminal of the loop control unit is connected to the first phase line, the second terminal of the loop control unit is connected to the second phase line, the third terminal of the loop control unit is connected to the third phase line, and the fourth terminal of the loop control unit is connected to the second power supply terminal of the auxiliary control module. The second power supply terminal of the auxiliary control module is connected to the neutral line. The loop control unit is used to control one of the first loop execution unit, the second loop execution unit, and the third loop execution unit connected to the non-missing phase line to conduct in response to a phase loss.
3. The phase loss protection circuit according to claim 2, characterized in that, The control circuit module includes a first relay, a second relay, and a third relay. The first relay includes a first coil, a first normally open contact, a second normally open contact, a third normally open contact, and a first normally closed contact. The second relay includes a second coil, a fourth normally open contact, a fifth normally open contact, a sixth normally open contact, and a second normally closed contact. The third relay includes a third coil, a seventh normally open contact, an eighth normally open contact, a ninth normally open contact, and a third normally closed contact. The circuit control unit includes a first coil, a second coil, and a third coil. The first coil is connected between the first phase line and the second power supply terminal of the auxiliary control module. The second coil is connected between the second phase line and the second power supply terminal of the auxiliary control module. The third coil is connected between the third phase line and the second power supply terminal of the auxiliary control module. The first circuit execution unit includes a first circuit and a second circuit. The first circuit includes a first normally open contact, a fourth normally open contact, and a seventh normally open contact connected in series between the first phase line and the first power supply terminal of the auxiliary control module. The second circuit includes a second normally open contact, a fifth normally open contact, and a third normally closed contact connected in series between the first phase line and the first power supply terminal of the auxiliary control module. The second circuit execution unit includes a third circuit, which includes a first normally closed contact, a sixth normally open contact, and an eighth normally open contact connected in series between the second phase line and the first power supply terminal of the auxiliary control module. The third circuit execution unit includes a fourth circuit, which includes a third normally open contact, a second normally closed contact, and a ninth normally open contact connected in series between the third phase line and the first power supply terminal of the auxiliary control module.
4. The phase loss protection circuit according to claim 3, characterized in that, The first relay further includes a tenth normally open contact, the second relay further includes a sixth normally closed contact, and the third relay further includes an eighth normally closed contact; The first circuit execution unit further includes a fifth circuit, which includes the tenth normally open contact, the sixth normally closed contact, and the eighth normally closed contact connected in series between the first phase line and the first power supply terminal of the auxiliary control module.
5. The phase loss protection circuit according to claim 3, characterized in that, The first relay further includes a fourth normally closed contact, the second relay further includes an eleventh normally open contact, and the third relay further includes a ninth normally closed contact; The second circuit execution unit further includes a sixth circuit, which includes the fourth normally closed contact, the eleventh normally open contact, and the ninth normally closed contact connected in series between the second phase line and the first power supply terminal of the auxiliary control module.
6. The phase loss protection circuit according to claim 3, characterized in that, The first relay further includes a fifth normally closed contact, the second relay further includes a seventh normally closed contact, and the third relay further includes a twelfth normally open contact; The third circuit execution unit also includes a seventh circuit, which includes the fifth normally closed contact, the seventh normally closed contact, and the twelfth normally open contact connected in series between the third phase line and the first power supply terminal of the auxiliary control module.
7. The phase loss protection circuit according to claim 3, characterized in that, The first relay further includes a thirteenth normally open contact, the second relay further includes a fourteenth normally open contact, and the third relay further includes a fifteenth normally open contact; The phase loss protection circuit further includes a fourth relay, which includes a fourth coil and a sixteenth normally open contact. The sixteenth normally open contact is connected to the first phase line, the second phase line, and the third phase line respectively. The fourth coil, the thirteenth normally open contact, the fourteenth normally open contact, and the fifteenth normally open contact are connected in series between the first sub-terminal and the second sub-terminal of the output terminal of the auxiliary control module.
8. A control method for a phase loss protection circuit, characterized in that, The phase loss protection circuit includes a three-phase power input module, a main circuit module, a control circuit module, and an auxiliary control module. The input terminal of the main circuit module is connected to the three-phase power input module via a three-phase line, and the output terminal of the main circuit module is connected to the motor. The control method for the phase loss protection circuit includes: When a phase is missing in the three-phase circuit, the main circuit module is disconnected from the motor by the control circuit module, and at the same time, one phase of the three-phase circuit that is not missing a phase is controlled to supply power to the auxiliary control module.
9. The control method for the phase loss protection circuit according to claim 8, characterized in that, The control loop module includes a loop control unit, a first loop execution unit, a second loop execution unit, and a third loop execution unit; the first loop execution unit includes a first loop, a second loop, and a fifth loop; the second loop execution unit includes a third loop and a sixth loop; and the third loop execution unit includes a fourth loop and a seventh loop. When a phase is lost in the three-phase circuit, the main circuit module is disconnected from the motor by the control circuit module, and simultaneously one phase of the three-phase circuit that is not missing supplies power to the auxiliary control module, including: When a single phase in the three-phase circuit is missing, the control circuit control unit responds to the missing phase by controlling one of the two circuits connected to the non-missing phase line in the second circuit, the third circuit, and the fourth circuit to conduct, thereby supplying power to the auxiliary control module; wherein, the two circuits connected to the non-missing phase line do not conduct simultaneously. When two phases of the three-phase circuit are missing, the control circuit control unit responds to the missing phase by controlling one of the five, six, or seven circuits connected to the non-missing phase circuit to conduct, thereby supplying power to the auxiliary control module.
10. An air conditioning control system, characterized in that, Includes the phase loss protection circuit as described in any one of claims 1-7.