An air conditioning system

Abstract

The embodiment of the application provides an air conditioning system, and relates to the technical field of electrical appliances. The air conditioning system realizes interlocking function through the addition of a protection circuit. The air conditioning system comprises at least one variable frequency driving module, wherein the variable frequency driving module comprises a driving chip, a protection circuit, a first variable frequency circuit and a second variable frequency circuit; the output end of the variable frequency driving module is electrically connected with a load; the driving chip is electrically connected with the first end of the first variable frequency circuit and the first end of the protection circuit; the second end of the protection circuit is electrically connected with the first end of the second variable frequency circuit; the second end of the first variable frequency circuit is electrically connected with a first voltage signal end, the third end of the first variable frequency circuit is electrically connected with the output end and the second end of the second variable frequency circuit; the third end of the second variable frequency circuit is electrically connected with a second voltage signal end, the third end of the protection circuit is electrically connected with a third voltage signal end, and the fourth end of the protection circuit is electrically connected with a fourth voltage signal end.

Description

Technical Field

[0001] This invention relates to the field of electrical technology, and more particularly to an air conditioning system. Background Technology

[0002] With the development of science and technology, air conditioning is becoming more and more common, and more and more people's daily lives are closely related to air conditioning.

[0003] Current air conditioning systems involve both frequency conversion and drive technologies. In these fields, insulated-gate bipolar transistors (IGBTs) or field-effect transistors (FETs) are commonly used as switching devices. Taking IGBTs as an example, if there are two IGBTs in the same bridge arm, typically two single-channel driver chips or one dual-channel driver chip are needed to drive them. Furthermore, the two IGBTs in the same bridge arm must not be turned on simultaneously; doing so would cause a short circuit and damage the components. Summary of the Invention

[0004] This invention provides an air conditioning system in which the variable frequency drive module achieves interlocking functionality by adding a protection circuit.

[0005] The aforementioned air conditioning system includes: at least one variable frequency drive module, the variable frequency drive module including: a drive chip, a protection circuit, a first variable frequency circuit and a second variable frequency circuit; the output terminal of the variable frequency drive module is electrically connected to the load.

[0006] The driving chip is electrically connected to the first terminal of the first frequency converter circuit and also electrically connected to the first terminal of the protection circuit; the second terminal of the protection circuit is electrically connected to the first terminal of the second frequency converter circuit; the second terminal of the first frequency converter circuit is electrically connected to the first voltage signal terminal; the third terminal of the first frequency converter circuit is electrically connected to the output terminal and also electrically connected to the second terminal of the second frequency converter circuit; the third terminal of the second frequency converter circuit is electrically connected to the second voltage signal terminal; the third terminal of the protection circuit is electrically connected to the third voltage signal terminal; and the fourth terminal of the protection circuit is electrically connected to the fourth voltage signal terminal.

[0007] Specifically, when the driver chip outputs a first level, the protection circuit is turned on, the first frequency converter circuit is turned on, and the second frequency converter circuit is turned off; when the driver chip outputs a second level, the protection circuit is turned off, the first frequency converter circuit is turned off, and the second frequency converter circuit is turned on; the driver chip achieves the interlocking function of the first frequency converter circuit and the second frequency converter circuit by outputting the first level or the second level.

[0008] Based on the above technical solutions, in some embodiments provided in this application, a protection circuit is added to the frequency converter drive module. The drive chip in the frequency converter drive module is directly electrically connected to the protection circuit and the first frequency converter circuit, and indirectly electrically connected to the second frequency converter circuit through the protection circuit. When the drive chip outputs a first level, the first frequency converter circuit turns on after receiving the first level, and the protection circuit also turns on after receiving the first level; the protection circuit turns on so that the second frequency converter circuit receives the voltage of the fourth voltage signal terminal, and the second frequency converter circuit turns off. The first and second frequency converter circuits are not turned on simultaneously, so no short circuit occurs. When the drive chip outputs a second level, the first frequency converter circuit turns off after receiving the second level, and the protection circuit also turns off after receiving the second level; the protection circuit turns off so that the second frequency converter circuit receives the voltage of the third voltage signal terminal, and the second frequency converter circuit turns on. The first and second frequency converter circuits are not turned on simultaneously, so no short circuit occurs. The air conditioning system in this embodiment uses a driver chip to drive the first frequency converter circuit and the second frequency converter circuit. The protection circuit enables the first frequency converter circuit and the second frequency converter circuit to conduct alternately, preventing short circuits and effectively protecting the first frequency converter circuit and the second frequency converter circuit.

[0009] In some embodiments, the protection circuit includes a transistor; the control electrode of the transistor is electrically connected to a first terminal of the protection circuit; the first electrode of the transistor is electrically connected to a second terminal of the protection circuit; the second electrode of the transistor is electrically connected to a fourth terminal of the protection circuit; the transistor is configured to be turned on under the control of the first level and turned off under the control of the second level.

[0010] In some embodiments, the protection circuit further includes a first resistor; a first end of the first resistor is electrically connected to a third end of the protection circuit, and a second end of the first resistor is electrically connected to a first electrode of the transistor.

[0011] In some embodiments, the first frequency conversion circuit includes: a first power switch and a first diode; the control electrode of the first power switch is electrically connected to a first terminal of the first frequency conversion circuit, the first electrode of the first power switch is electrically connected to a second terminal of the first frequency conversion circuit, and the second electrode of the first power switch is electrically connected to the output terminal of the frequency conversion drive module.

[0012] The positive terminal of the first diode is electrically connected to the second terminal of the first power switch, and the negative terminal of the first diode is electrically connected to the first terminal of the first power switch.

[0013] The first power switch is configured to be turned on under the control of the first level and turned off under the control of the second level.

[0014] In some embodiments, the first frequency converter circuit further includes: a first turn-on resistor; a first end of the first turn-on resistor is electrically connected to a first end of the first frequency converter circuit, and a second end of the first turn-on resistor is electrically connected to the control electrode of the first power switch transistor.

[0015] In some embodiments, the second frequency conversion circuit includes: a second power switch and a second diode; the control terminal of the second power switch is electrically connected to the second terminal of the protection circuit, the first terminal of the second power switch is electrically connected to the output terminal of the frequency conversion drive module, and the second terminal of the second power switch is electrically connected to the third terminal of the second frequency conversion circuit.

[0016] The positive terminal of the second diode is electrically connected to the second terminal of the second power switch, and the negative terminal of the second diode is electrically connected to the first terminal of the second power switch.

[0017] The second power switch is turned on under the control of a third voltage signal and turned off under the control of a fourth voltage signal; the third voltage signal terminal is configured to provide the third voltage signal, and the fourth voltage signal terminal is configured to provide the fourth voltage signal.

[0018] In some embodiments, the second frequency converter circuit further includes: a second turn-on resistor; the first end of the second turn-on resistor is electrically connected to the first end of the second frequency converter circuit, and the second end of the second turn-on resistor is electrically connected to the control electrode of the second power switch.

[0019] In some embodiments, the frequency converter drive module further includes: a second resistor and a third resistor; a first end of the second resistor is electrically connected to the drive chip, and a second end of the second resistor is electrically connected to a first end of the protection circuit; a first end of the third resistor is electrically connected to a second end of the second resistor, and a second end of the third resistor is electrically connected to a fourth voltage signal terminal.

[0020] In some embodiments, the first power switch and the second power switch are insulated gate bipolar transistors or field-effect transistors.

[0021] In some embodiments, the transistor is a bipolar junction transistor (BJT). Attached Figure Description

[0022] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the technical solutions of the present invention, and do not constitute a limitation on the technical solutions of the present invention.

[0023] Figure 1 A schematic diagram of the composition of an air conditioning system provided in the prior art;

[0024] Figure 2 This is a schematic diagram of the composition of an air conditioning system provided in an embodiment of the present invention;

[0025] Figure 3 An internal block diagram of an air conditioning system provided in an embodiment of the present invention;

[0026] Figure 4 A system block diagram of a variable frequency drive module provided in an embodiment of the present invention;

[0027] Figure 5 An internal circuit diagram of a protection circuit provided in an embodiment of the present invention;

[0028] Figure 6 A circuit diagram of a protection circuit located in a frequency converter drive module, provided for an embodiment of the present invention;

[0029] Figure 7 An internal circuit diagram of another protection circuit provided in an embodiment of the present invention;

[0030] Figure 8 A circuit diagram of another protection circuit provided in an embodiment of the present invention located in the frequency converter drive module;

[0031] Figure 9 An internal circuit diagram of a first frequency conversion circuit provided in an embodiment of the present invention;

[0032] Figure 10 A circuit diagram of a first frequency conversion circuit located in a frequency conversion drive module, provided for an embodiment of the present invention;

[0033] Figure 11 An internal circuit diagram of another first frequency conversion circuit provided in an embodiment of the present invention;

[0034] Figure 12 A circuit diagram of another first frequency conversion circuit located in the frequency conversion drive module provided in an embodiment of the present invention;

[0035] Figure 13 An internal circuit diagram of a second frequency converter circuit provided in an embodiment of the present invention;

[0036] Figure 14 A circuit diagram of a second frequency conversion circuit located in a frequency conversion drive module, provided for an embodiment of the present invention;

[0037] Figure 15 An internal circuit diagram of another second frequency conversion circuit provided in an embodiment of the present invention;

[0038] Figure 16 A circuit diagram of another second frequency conversion circuit located in the frequency conversion drive module provided in an embodiment of the present invention;

[0039] Figure 17A circuit diagram of a frequency converter drive module provided in an embodiment of the present invention;

[0040] Figure 18 An internal circuit diagram of an air conditioning system provided in an embodiment of the present invention;

[0041] Figure 19 A flowchart illustrating the output of a high-level signal by a driver chip, provided in an embodiment of the present invention;

[0042] Figure 20 This is a flowchart illustrating a driver chip outputting a low level, as provided in an embodiment of the present invention. Detailed Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0045] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0046] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Furthermore, when describing pipelines, the terms "connected" and "linked" as used in this invention have the meaning of enabling conduction. The specific meaning needs to be understood in conjunction with the context.

[0047] In embodiments of the present invention, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" or "for example" in embodiments of the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0048] As described in the background section, current air conditioning systems involve both frequency conversion and drive technologies. In these fields, insulated-gate bipolar transistors (IGBTs) or field-effect transistors (FETs) are commonly used as switching devices. Taking an IGBT as an example, if there are two IGBTs in the same bridge arm, typically two single-channel driver chips or one dual-channel driver chip are needed to drive them. Furthermore, the upper and lower IGBTs in the same bridge arm must not be turned on simultaneously; doing so would cause a short circuit and damage the components.

[0049] like Figure 1 As shown, Figure 1 This refers to an existing air conditioning system. The air conditioning system includes a variable frequency drive module. For example... Figure 2 As shown, the air conditioning system 1000 includes: an indoor unit 100, an outdoor unit 200, and a wired controller 300. Figure 2 The inverter drive module is located in the outdoor unit, but it can also be located in the indoor unit. The following description of the inverter drive module focuses on the air conditioning system itself, without specifying its exact location.

[0050] Based on this, embodiments of this application provide an air conditioning system. For example... Figure 3 As shown, the air conditioning system 1000 includes at least one variable frequency drive module 10. The output terminal 51 of the variable frequency drive module 10 is electrically connected to the load 600.

[0051] In some embodiments, the load 600 is a compressor or a motor.

[0052] like Figure 4 As shown, the frequency conversion drive module 10 includes: a drive chip 1, a protection circuit 2, a first frequency conversion circuit 3, and a second frequency conversion circuit 4.

[0053] The protection circuit 2 includes: a first terminal 21, a second terminal 22, a third terminal 23, and a fourth terminal 24; the first frequency converter circuit 3 includes: a first terminal 31, a second terminal 32, and a third terminal 33; the second frequency converter circuit 4 includes: a first terminal 41, a second terminal 42, and a third terminal 43.

[0054] The aforementioned variable frequency drive module 10 further includes: a first voltage signal terminal 5, a second voltage signal terminal 6, a third voltage signal terminal 7, and a fourth voltage signal terminal 8.

[0055] The driver chip 1 is electrically connected to the first terminal 31 of the first frequency converter circuit 3 and also to the first terminal 21 of the protection circuit 2; the second terminal 22 of the protection circuit 2 is electrically connected to the first terminal of the second frequency converter circuit 4; the second terminal of the first frequency converter circuit is electrically connected to the first voltage signal terminal 5; the third terminal 33 of the first frequency converter circuit 3 is electrically connected to the output terminal 51 and also to the second terminal 42 of the second frequency converter circuit 4; the third terminal 43 of the second frequency converter circuit 4 is electrically connected to the second voltage signal terminal 6; the third terminal 23 of the protection circuit 2 is electrically connected to the third voltage signal terminal 7; and the fourth terminal 24 of the protection circuit 2 is electrically connected to the fourth voltage signal terminal GND.

[0056] Specifically, when the driver chip 1 outputs the first level, the protection circuit 2 is turned on, the first frequency conversion circuit 3 is turned on, and the second frequency conversion circuit 4 is turned off; when the driver chip 1 outputs the second level, the protection circuit 2 is turned off, the first frequency conversion circuit 3 is turned off, and the second frequency conversion circuit 4 is turned on; the driver chip 1 realizes the interlocking function of the first frequency conversion circuit 3 and the second frequency conversion circuit 4 by outputting the first level or the second level.

[0057] In some embodiments, the first voltage signal terminal 5 is a DC power supply signal terminal VDC, the second voltage signal terminal 6 is a ground terminal GND, the third voltage signal terminal 7 is a power supply voltage signal terminal VCC, and the fourth voltage signal terminal 8 is a ground terminal GND. The second voltage signal terminal 6 and the fourth voltage signal terminal 8 share the same ground terminal GND.

[0058] In some embodiments provided in this application, a protection circuit 2 is added to the frequency converter drive module 10. The drive chip 1 in the frequency converter drive module 10 is directly electrically connected to the protection circuit 2 and the first frequency converter circuit 3, and indirectly electrically connected to the second frequency converter circuit 4 through the protection circuit 2. When the drive chip 1 outputs a first level, the first frequency converter circuit 3 conducts upon receiving the first level, and the protection circuit 2 also conducts upon receiving the first level. The conduction of the protection circuit 2 causes the second frequency converter circuit 4 to receive the voltage from the fourth voltage signal terminal 8, causing the second frequency converter circuit 4 to turn off. Since the first frequency converter circuit 3 and the second frequency converter circuit 4 are not simultaneously turned on, a short circuit will not occur. When the drive chip 1 outputs a second level, the first frequency converter circuit 3 turns off upon receiving the second level, and the protection circuit 2 also turns off upon receiving the second level. The turn-off of the protection circuit 2 causes the second frequency converter circuit 4 to receive the voltage from the third voltage signal terminal 7, causing the second frequency converter circuit 4 to conduct. Since the first frequency converter circuit 3 and the second frequency converter circuit 4 are not simultaneously turned on, a short circuit will not occur. The air conditioning system in this embodiment uses a single-channel driver chip to drive the first frequency converter circuit and the second frequency converter circuit. The first frequency converter circuit and the second frequency converter circuit are interleaved through the protection circuit, so that no short circuit will occur, and the first frequency converter circuit and the second frequency converter circuit are effectively protected.

[0059] like Figure 5 and Figure 6 As shown, the protection circuit 2 includes a transistor Q1; the control electrode of the transistor Q1 is electrically connected to the first terminal 21 of the protection circuit 2; the first electrode of the transistor Q1 is electrically connected to the second terminal 22 of the protection circuit 2; and the second electrode of the transistor Q1 is electrically connected to the fourth terminal 24 of the protection circuit 2.

[0060] Transistor Q1 is configured to turn on under the control of a first level and turn off under the control of a second level.

[0061] In some embodiments, transistor Q1 is a general-purpose transistor. This general-purpose transistor is selected with a low collector-emitter saturation voltage drop VCE(sat), ideally below 200mV. Selecting a general-purpose transistor with this parameter can also better achieve the interlocking function.

[0062] It should be noted that, Figure 5 and Figure 6 The transistor in the circuit is an NPN transistor. An NPN transistor conducts when it receives a high-level signal and is cut off when it receives a low-level signal. At this time, the first level is high and the second level is low.

[0063] If the transistor is a PNP type, the first frequency converter circuit 3 and the second frequency converter circuit 4 also need to be replaced accordingly. A PNP type transistor is cut off when receiving a high level and turns on when receiving a low level. At this time, the first level is low and the second level is high.

[0064] like Figure 7 and Figure 8 As shown, the protection circuit also includes a first resistor R1; the first end of the first resistor R1 is electrically connected to the third end 23 of the protection circuit 2, and the second end of the first resistor R1 is electrically connected to the first electrode of the transistor Q1.

[0065] The first resistor R1 serves to limit the current. When transistor Q1 is in the on state, without the first resistor R1, the third voltage signal terminal 7 and the fourth voltage signal terminal 8 would be directly connected, which could easily cause a short circuit in the protection circuit; however, by adding the first resistor R1, a short circuit in the protection circuit can be prevented.

[0066] like Figure 9 and Figure 10 As shown, the first frequency conversion circuit 3 includes: a first power switch Q2 and a first diode D1.

[0067] The control terminal of the first power switch Q2 is electrically connected to the first terminal 31 of the first frequency converter circuit 3, the first terminal of the first power switch Q2 is electrically connected to the second terminal 32 of the first frequency converter circuit 3, and the second terminal of the first power switch Q2 is electrically connected to the output terminal 51 of the frequency converter drive module 10.

[0068] The positive terminal of the first diode D1 is electrically connected to the second terminal of the first power switch Q2, and the negative terminal of the first diode D1 is electrically connected to the first terminal of the first power switch Q2.

[0069] The first power switch Q2 is configured to be turned on under the control of the first level and turned off under the control of the second level.

[0070] In some embodiments, the first power switch Q2 is a field-effect transistor or an insulated-gate bipolar transistor.

[0071] Metal-oxide-semiconductor field-effect transistors (MOSFETs) are semiconductor devices widely used for switching purposes and amplifying electronic signals in electronic devices. Due to their extremely small size, MOSFETs can be both the core component and an integrated circuit, allowing for design and fabrication on a single chip. The introduction of MOSFET devices has brought about changes in the field of electronic switching.

[0072] An insulated-gate bipolar transistor (IGBT) is a composite, fully controllable, voltage-driven power semiconductor device composed of a bipolar junction transistor (BJT) and a metal-oxide-semiconductor field-effect transistor (MOS). It combines the advantages of the high input impedance of a metal-oxide-semiconductor field-effect transistor (MOSFET) and the low on-state voltage drop of a giant transistor (GTR).

[0073] Metal-oxide-semiconductor (MOSFET) field-effect transistors (FETs) and insulated-gate bipolar transistors (IGBTs) are unidirectional devices; they conduct current only when forward-biased and block current when reverse-biased. Therefore, connecting an external diode across a MOSFET or IGBT can provide a reverse current path; for example, Figure 9 and Figure 10 The first diode D1 in the middle.

[0074] In other words, when the driver chip 1 outputs the first level, the first power switch Q2 is turned on when it receives the first level, and the first voltage signal terminal 5 provides DC voltage to the first frequency conversion circuit 3. At this time, the first power switch Q2 is in working state.

[0075] When the driver chip 1 outputs the second level, the first power switch Q2 is cut off when it receives the second level, and the first voltage signal terminal 5 cannot provide DC voltage to the first frequency conversion circuit 3. At this time, the first power switch Q2 is in a non-working state.

[0076] like Figure 11 and Figure 12 As shown, the first frequency conversion circuit 3 also includes a first turn-on resistor R2.

[0077] The first end of the first turn-on resistor R2 is electrically connected to the first end 31 of the first frequency converter circuit 3, and the second end of the first turn-on resistor R2 is electrically connected to the control electrode of the first power switch Q2.

[0078] The first turn-on resistor R2 is configured to reduce the oscillation of the first frequency converter circuit 3 and at the same time share the drive power of the first frequency converter circuit 3.

[0079] like Figure 13 and Figure 14 As shown, the second frequency conversion circuit 4 includes: a second power switch Q3 and a second diode D2.

[0080] The control terminal of the second power switch Q3 is electrically connected to the second terminal of the protection circuit, the first terminal of the second power switch Q3 is electrically connected to the output terminal of the frequency converter drive module, and the second terminal of the second power switch Q3 is electrically connected to the third terminal of the second frequency converter circuit.

[0081] The positive terminal of the second diode D2 is electrically connected to the second terminal of the second power switch Q3, and the negative terminal of the second diode D2 is electrically connected to the first terminal of the second power switch Q3.

[0082] The second power switch Q3 is turned on under the control of the third voltage signal and turned off under the control of the fourth voltage signal; the third voltage signal terminal 7 is configured to provide the third voltage signal, and the fourth voltage signal terminal 8 is configured to provide the fourth voltage signal.

[0083] In some embodiments, the second power switch Q3 is a field-effect transistor (FET) or an insulated-gate bipolar transistor (IGBT). The description of FETs and IGBTs is the same as that of the first power switch Q2 described above. The description of the second diode D2 is the same as that of the first diode D1 described above.

[0084] In other words, when the driver chip 1 outputs the first level, the protection circuit 2 receives the first level and then conducts. At this time, the third voltage signal terminal 7 and the fourth voltage signal terminal 8 are directly connected. The level received by the second power switch Q3 is the level of the fourth voltage signal terminal 8. When the level of the fourth voltage signal terminal 8 is low, the second power switch Q3 cannot conduct and is in a non-working state.

[0085] When the driver chip 1 outputs the second level, the protection circuit 2 receives the second level and then cuts off. At this time, the third voltage signal terminal 7 and the fourth voltage signal terminal 8 are in an open state. The level received by the second power switch Q3 is the level of the third voltage signal terminal 7. When the level of the third voltage signal terminal 7 is high, the second power switch Q3 is turned on and is in the working state.

[0086] like Figure 15 and Figure 16 As shown, the second frequency conversion circuit 4 also includes: a second turn-on resistor R3;

[0087] The first end of the second turn-on resistor R3 is electrically connected to the first end 41 of the second frequency converter circuit 4, and the second end of the second turn-on resistor R3 is electrically connected to the control electrode of the second power switch Q3.

[0088] The second turn-on resistor R3 is configured to reduce the oscillation of the second frequency converter circuit 4 and at the same time share the drive power of the second frequency converter circuit 4.

[0089] like Figure 17 As shown, the frequency converter drive module 10 also includes: a second resistor R4 and a third resistor R5;

[0090] The first end of the second resistor R4 is electrically connected to the driver chip 1, and the second end of the second resistor R4 is electrically connected to the first end 21 of the protection circuit 2; the first end of the third resistor R5 is electrically connected to the second end of the second resistor R4, and the second end of the third resistor R5 is electrically connected to the fourth voltage signal terminal 8.

[0091] The second resistor R4 and the third resistor R5 are configured as a voltage divider.

[0092] In summary, referring to Figure 17 and Figure 18 The driver chip 1 is electrically connected to the first terminal of the first turn-on resistor R2; the control terminal of the first power switch Q2 is electrically connected to the second terminal of the first turn-on resistor R2; the first terminal of the first power switch Q2 is electrically connected to the first voltage signal terminal 5; and the second terminal of the first power switch Q2 is electrically connected to the load 600.

[0093] The positive terminal of the first diode D1 is electrically connected to the second terminal of the first power switch Q2, and the negative terminal of the first diode D1 is electrically connected to the first terminal of the first power switch Q2.

[0094] The driver chip 1 is also electrically connected to the first terminal of the second resistor R4; the control terminal of transistor Q1 is electrically connected to the second terminal of the second resistor R4, the first terminal of transistor Q1 is electrically connected to the second terminal of the first resistor R1, the first terminal of transistor Q1 is also electrically connected to the first terminal of the second turn-on resistor R3, and the second terminal of transistor Q1 is electrically connected to the fourth voltage signal terminal 8. The first terminal of the first resistor R1 is electrically connected to the third voltage signal terminal.

[0095] The first end of the third resistor R5 is electrically connected to the second end of the second resistor R4, and the second end of the third resistor R5 is electrically connected to the fourth voltage signal terminal 8.

[0096] The control terminal of the second power switch Q3 is electrically connected to the second terminal of the second turn-on resistor R3, the first terminal of the second power switch Q3 is electrically connected to the second terminal of the first power switch Q2, and the second terminal of the second power switch Q3 is electrically connected to the second voltage signal terminal 6.

[0097] The positive terminal of the second diode D2 is electrically connected to the second terminal of the second power switch Q3, and the negative terminal of the second diode D2 is electrically connected to the first terminal of the second power switch Q3.

[0098] If the driver chip 1 outputs the first level, transistor Q1 receives the first level and turns on, and the first power switch Q2 receives the first level and turns on; when transistor Q1 is on, the third voltage signal terminal 7 and the fourth voltage signal terminal 8 are connected, the second power switch Q3 receives the voltage of the fourth voltage signal terminal 8 and cannot turn on, and the second power switch Q3 is turned off.

[0099] If the driver chip 1 outputs the second level, transistor Q1 receives the second level and is cut off, and the first power switch Q2 receives the second level and is cut off; when transistor Q1 is cut off, the third voltage signal terminal 7 and the fourth voltage signal terminal 8 cannot be connected, the second power switch Q3 receives the voltage of the third voltage signal terminal 7, and the second power switch Q3 is turned on.

[0100] When the driver chip 1 outputs the first level, the first power switch Q2 is turned on and the second power switch Q3 is turned off; when the driver chip 1 outputs the second level, the first power switch Q2 is turned off and the second power switch Q3 is turned on. In other words, the frequency converter drive module 10 can achieve the interlock function by using the protection circuit to ensure that the first power switch Q2 and the second power switch Q3 are in different states at the same time, thereby further protecting the first power switch Q2 and the second power switch Q3.

[0101] To facilitate understanding of the solution in this application, the following flowcharts will specifically illustrate the states of the first and second frequency conversion circuits when the driver chip outputs the first and second levels.

[0102] like Figure 19 As shown, taking the first level output by the driver chip as an example, the states of the first and second frequency conversion circuits are described in detail, and the process is as follows:

[0103] S11, the driver chip outputs a high level.

[0104] S12, the first frequency converter circuit receives a high level, and the protection circuit receives a high level.

[0105] S13, the first frequency converter circuit is turned on, and the protection circuit is turned on.

[0106] With the protection circuit activated, the third voltage signal terminal transmits the voltage to the second frequency converter circuit.

[0107] S14, the second frequency conversion circuit receives a low level.

[0108] S15, the second frequency converter circuit is cut off.

[0109] S16, Interlock protection between the first frequency converter circuit and the second frequency converter circuit.

[0110] like Figure 20 As shown, taking the first level output by the driver chip as an example, the states of the first and second frequency conversion circuits are described in detail, and the process is as follows:

[0111] S21, the driver chip outputs a low level.

[0112] S22, the first frequency converter circuit receives a low level, and the protection circuit receives a low level.

[0113] S23, the first frequency converter circuit is cut off, and the protection circuit is cut off.

[0114] When the protection circuit is off, the fourth voltage signal terminal transmits the voltage to the second frequency converter circuit.

[0115] S24, the second frequency conversion circuit receives a high level.

[0116] S25, the second frequency converter circuit is turned on.

[0117] S26. Interlock protection between the first frequency converter circuit and the second frequency converter circuit.

[0118] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An air conditioning system, characterized in that, include: At least one variable frequency drive module, the variable frequency drive module comprising: a drive chip, a protection circuit, a first variable frequency circuit and a second variable frequency circuit; The output terminal of the frequency converter drive module is electrically connected to the load. The driving chip is electrically connected to the first terminal of the first frequency converter circuit and also electrically connected to the first terminal of the protection circuit; the second terminal of the protection circuit is electrically connected to the first terminal of the second frequency converter circuit; the second terminal of the first frequency converter circuit is electrically connected to the first voltage signal terminal; the third terminal of the first frequency converter circuit is electrically connected to the output terminal and also electrically connected to the second terminal of the second frequency converter circuit; the third terminal of the second frequency converter circuit is electrically connected to the second voltage signal terminal; the third terminal of the protection circuit is electrically connected to the third voltage signal terminal; and the fourth terminal of the protection circuit is electrically connected to the fourth voltage signal terminal. Specifically, when the driver chip outputs a first level, the protection circuit is turned on, the first frequency conversion circuit is turned on, and the second frequency conversion circuit is turned off. When the driver chip outputs the second level, the protection circuit is turned off, the first frequency conversion circuit is turned off, and the second frequency conversion circuit is turned on. The driver chip achieves the interlocking function between the first frequency conversion circuit and the second frequency conversion circuit by outputting the first level or the second level.

2. The air conditioning system according to claim 1, characterized in that, The protection circuit includes a transistor; the control electrode of the transistor is electrically connected to a first terminal of the protection circuit; the first electrode of the transistor is electrically connected to a second terminal of the protection circuit; and the second electrode of the transistor is electrically connected to a fourth terminal of the protection circuit. The transistor is configured to be turned on under the control of the first level and turned off under the control of the second level.

3. The air conditioning system according to claim 2, characterized in that, The protection circuit also includes a first resistor; The first end of the first resistor is electrically connected to the third end of the protection circuit, and the second end of the first resistor is electrically connected to the first electrode of the transistor.

4. The air conditioning system according to any one of claims 1 to 3, characterized in that, The first frequency conversion circuit includes: a first power switching transistor and a first diode; The control terminal of the first power switch is electrically connected to the first terminal of the first frequency converter circuit, the first terminal of the first power switch is electrically connected to the second terminal of the first frequency converter circuit, and the second terminal of the first power switch is electrically connected to the output terminal of the frequency converter drive module. The positive terminal of the first diode is electrically connected to the second terminal of the first power switch, and the negative terminal of the first diode is electrically connected to the first terminal of the first power switch. The first power switch is configured to be turned on under the control of the first level and turned off under the control of the second level.

5. The air conditioning system according to claim 4, characterized in that, The first frequency converter circuit further includes: a first turn-on resistor; The first end of the first turn-on resistor is electrically connected to the first end of the first frequency converter circuit, and the second end of the first turn-on resistor is electrically connected to the control electrode of the first power switch.

6. The air conditioning system according to claim 5, characterized in that, The second frequency conversion circuit includes: a second power switch and a second diode; The control terminal of the second power switch is electrically connected to the second terminal of the protection circuit, the first terminal of the second power switch is electrically connected to the output terminal of the frequency converter drive module, and the second terminal of the second power switch is electrically connected to the third terminal of the second frequency converter circuit. The positive terminal of the second diode is electrically connected to the second terminal of the second power switch, and the negative terminal of the second diode is electrically connected to the first terminal of the second power switch. The second power switch is turned on under the control of a third voltage signal and turned off under the control of a fourth voltage signal; the third voltage signal terminal is configured to provide the third voltage signal, and the fourth voltage signal terminal is configured to provide the fourth voltage signal.

7. The air conditioning system according to claim 6, characterized in that, The second frequency converter circuit further includes: a second turn-on resistor; The first end of the second turn-on resistor is electrically connected to the first end of the second frequency converter circuit, and the second end of the second turn-on resistor is electrically connected to the control electrode of the second power switch.

8. The air conditioning system according to claim 7, characterized in that, The frequency converter drive module further includes: a second resistor and a third resistor; The first end of the second resistor is electrically connected to the driver chip, and the second end of the second resistor is electrically connected to the first end of the protection circuit. The first end of the third resistor is electrically connected to the second end of the second resistor, and the second end of the third resistor is electrically connected to the fourth voltage signal terminal.

9. The air conditioning system according to claim 8, characterized in that, The first power switch and the second power switch are insulated gate bipolar transistors or field-effect transistors.

10. The air conditioning system according to claim 9, characterized in that, The transistor is a triode.

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