A frequency converter driving circuit, a frequency converter and a compressor
By connecting a capacitor and a resistor in parallel to the gate of the MOSFET and reducing the resistance value of the voltage divider resistor, the problem of slow MOSFET driving speed in the inverter drive circuit is solved, and the MOSFET's fast turn-on and stability are improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- QINGDAO WANBAO COMPRESSOR
- Filing Date
- 2025-08-21
- Publication Date
- 2026-07-24
AI Technical Summary
The driving speed of MOSFETs in existing frequency converter drive circuits is slow, resulting in severe heat generation and easy damage. This is especially true for high-efficiency MOSFET solutions, where the traditional resistor voltage divider method slows down the turn-on speed.
A capacitor and a resistor are connected in parallel at the gate of the MOSFET to reduce the resistance of the original voltage divider resistor. The method of using a resistor in parallel with a capacitor accelerates the driving speed and ensures the stable and reliable conduction of the MOSFET.
By adding a parallel structure of capacitors and resistors, the turn-on speed of the MOSFET is significantly accelerated, the risk of overheating is reduced, and the reliability and stability of the MOSFET are improved.
Smart Images
Figure CN224555465U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of compressor technology, and relates to a frequency converter drive circuit, a frequency converter, and a compressor. Background Technology
[0002] To reduce power consumption, existing frequency converters mostly use high-efficiency MOSFET solutions. Some MOSFETs have a drive voltage of around 6V, but the drive power supply of existing frequency converters is around 15V. Therefore, a voltage divider circuit is needed to drive MOSFETs with a voltage of around 6V.
[0003] like Figure 2 As shown, traditional inverter drive circuits directly use a resistor voltage divider. This resistor voltage divider method results in slow drive speed and carries the risk of damaging the MOSFET. Specifically, since the traditional power supply is 15V, while the MOSFET's drive voltage is 6V, a resistor voltage divider can drive the MOSFET. However, due to the increased voltage divider resistor, the MOSFET's turn-on speed is slowed down. Since the MOSFET's internal resistance is at its maximum during turn-on, this leads to severe heat generation, potentially causing damage to the MOSFET. Utility Model Content
[0004] The purpose of this invention is to propose a frequency converter drive circuit. Based on the original circuit, a capacitor and a resistor are added to the gate terminal of the MOSFET and connected in parallel. At the same time, the resistance value of the original voltage divider resistor is reduced to speed up the MOSFET drive, reduce the risk of damaging the MOSFET, and thus ensure the stable and reliable conduction of the MOSFET.
[0005] To achieve the above objectives, this utility model adopts the following technical solution: A frequency converter drive circuit includes three-phase drive circuits of U, V and W; wherein each phase drive circuit includes a high-voltage side drive and discharge circuit and a low-voltage side drive and discharge circuit. The control terminal of the high-voltage side / low-voltage side drive and discharge circuit is used to connect to the high-voltage side / low-voltage side output of the driver chip, and is used to control the conduction and turn-off of the MOS transistor in the high-voltage side / low-voltage side drive and discharge circuit. The high-voltage / low-voltage driving and discharging circuit, based on the original high-voltage / low-voltage driving and discharging circuit using a resistor voltage divider structure, adds a capacitor and a resistor at the gate terminal of the MOS transistor. Among them, the newly added capacitors and resistors are set in parallel; at the same time, based on the original high-voltage / low-voltage side drive and discharge circuit using a resistor voltage divider structure, the resistance value of the original voltage divider resistor is reduced to obtain a new voltage divider resistor. The sum of the resistance values of the new voltage divider resistor and the newly added resistor is equal to the resistance value of the original voltage divider resistor.
[0006] Preferably, the resistance value of the original voltage divider resistor is 8-12 times the resistance value of the new voltage divider resistor.
[0007] Furthermore, based on the aforementioned inverter drive circuit, this utility model describes an inverter that includes a control module, a power supply module, a communication module, a sampling feedback module, and a drive module.
[0008] The drive module uses the frequency converter drive circuit described above.
[0009] Furthermore, based on the aforementioned frequency converter, this utility model also proposes a compressor that uses the aforementioned frequency converter.
[0010] This utility model has the following advantages: As described above, this utility model relates to a frequency converter drive circuit, a frequency converter, and a compressor. The high-voltage / low-voltage side drive and discharge circuit in the frequency converter drive circuit is improved compared to the original high-voltage / low-voltage side drive and discharge circuit which uses a resistor voltage divider structure, as follows: First, a capacitor and a resistor are added to the gate of the MOSFET, and the added capacitor and resistor are connected in parallel; Second, the resistance value of the voltage divider resistor in the original high-voltage / low-voltage side drive and discharge circuit is reduced to obtain a new voltage divider resistor. The resistance value of the new voltage divider resistor is significantly lower than that of the original voltage divider resistor, and the sum of the resistance values of the new voltage divider resistor and the added resistor is equal to the resistance value of the original voltage divider resistor. The improved drive voltage divider circuit, using a resistor in parallel with a capacitor, can accelerate the drive speed. This is achieved by adding a capacitor and a resistor to the original circuit. The new voltage divider resistor has a lower resistance value. When the MOSFET is turned on, the capacitor acts as a short circuit, and the voltage first charges the MOSFET through the new voltage divider resistor and capacitor, significantly accelerating the MOSFET's turn-on speed. This effectively prevents the MOSFET from overheating during turn-on, reducing the risk of damage and ensuring stable and reliable MOSFET conduction. Attached Figure Description
[0011] Figure 1 This is a structural block diagram of the inverter drive circuit in Embodiment 1 of this utility model; Figure 2 This is a block diagram of the structure of a frequency converter drive circuit in the prior art; Figure 3 This is a block diagram of the inverter structure in Embodiment 2 of this utility model. Detailed Implementation
[0012] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: Example 1 This embodiment 1 describes a frequency converter drive circuit to solve the technical problem in traditional frequency converter drive circuits where the driving speed of low-voltage drive inverter devices is slow, leading to easy damage to low-voltage MOS.
[0013] like Figure 1 As shown, the inverter drive circuit in this embodiment includes three-phase drive circuits of U, V, and W; each phase drive circuit includes a high-voltage side drive and discharge circuit and a low-voltage side drive and discharge circuit, for a total of six circuits.
[0014] The control terminal of the high-voltage side / low-voltage side drive and discharge circuit is used to connect to the high-voltage side / low-voltage side output of the driver chip, and is used to control the conduction and turn-off of the MOS transistor in the high-voltage side / low-voltage side drive and discharge circuit.
[0015] Taking the U-phase high-voltage side drive circuit as an example, the high-voltage side drive and discharge circuit in this embodiment is based on the original high-voltage side drive and discharge circuit using a resistor voltage divider structure (such as...). Figure 2 As shown), the following improvements were made: Add a capacitor and a resistor to the gate of the MOSFET, for example, the first capacitor C1 and the nineteenth resistor R19.
[0016] The newly added capacitors and resistors are connected in parallel; at the same time, based on the original high-voltage side drive and discharge circuit which uses a resistor voltage divider structure, the resistance value of the original voltage divider resistor R1' is reduced to obtain a new voltage divider resistor R1.
[0017] like Figure 2 As shown, in the original high-voltage side drive and discharge circuit, the voltage divider resistor R1' and the third resistor R3 formed a voltage divider circuit. The original value of the voltage divider resistor R1' was, for example, 3KΩ, and the value of the third resistor R3 was, for example, 10KΩ.
[0018] The original voltage divider resistor R1' has a resistance value that is 8-12 times that of the new voltage divider resistor R1. In this embodiment, R1' is, for example, 10 times that of R1, i.e., R1 has a value of 300Ω.
[0019] The sum of the resistance values of the new voltage divider resistor and the newly added resistor is equal to the resistance value of the original voltage divider resistor.
[0020] The improved drive voltage divider circuit, using a resistor in parallel with a capacitor, can accelerate the drive speed. This is achieved by adding a capacitor and a resistor to the original circuit. The new voltage divider resistor has a lower resistance value. When the MOSFET is turned on, the capacitor acts as a short circuit, and the voltage first charges the MOSFET through the new voltage divider resistor and capacitor, accelerating the MOSFET's turn-on speed. This effectively prevents the MOSFET from overheating during turn-on, reducing the risk of damage and ensuring stable and reliable MOSFET conduction.
[0021] Similarly, in this embodiment, the low-voltage side drive and discharge circuit is based on the original low-voltage side drive and discharge circuit that uses a resistor voltage divider structure (e.g. Figure 2 As shown in the figure, the same improvements were made to obtain the result.
[0022] The following is in conjunction with the appendix Figure 1 The specific structures of the high-voltage side drive and discharge circuit and the low-voltage side drive and discharge circuit in each phase drive circuit after the structural changes are described in detail.
[0023] The high-voltage side drive and discharge circuit of the U-phase drive circuit includes a first resistor R1, a second resistor R2, a third resistor R3, a first MOSFET Q1, a first diode D1, a second diode D2, a first capacitor C1, and a nineteenth resistor R19.
[0024] One end of the first resistor R1 and the second resistor R2 are connected together and connected to the control terminal HOU. The control terminal HOU is connected to the high-voltage side output of the U phase of the driver chip and is used to control the conduction and turn-off of the first MOSFET Q1.
[0025] In this embodiment, the first MOS transistor Q1 is, for example, an N-type GAN MOS transistor.
[0026] The other end of the second resistor R2 is connected to the negative terminal of the first diode D1; the positive terminal of the first diode D1, the other end of the first resistor R1, the first capacitor C1, and one end of the nineteenth resistor R19 are connected.
[0027] The first capacitor C1 and the other end of the nineteenth resistor R19 are connected to the gate terminal of the first MOS transistor Q1 and one end of the third resistor R3; the other end of the third resistor R3 is connected to the source terminal of the first MOS transistor Q1.
[0028] The first capacitor C1 and the nineteenth resistor R19 are newly added capacitors and resistors, and they are connected in parallel.
[0029] The first resistor R1 is obtained by reducing the original voltage divider resistor R1' (e.g., Figure 2 The new voltage divider resistor is obtained by changing the resistance value of the first resistor R1 and the nineteenth resistor R19, and the sum of the resistance values of the first resistor R1 and the nineteenth resistor R19 is equal to the resistance value of the original voltage divider resistor.
[0030] The original voltage divider resistor R1' had a resistance in the kiloohm range, such as 3KΩ, and R1' was 8-12 times the resistance of the new voltage divider resistor. Therefore, the resistance of the new voltage divider resistor (i.e., the first resistor R1) is only in the hundred-ohm range, and the resistance is significantly reduced.
[0031] At the instant the first MOSFET Q1 is turned on, the gate of the first MOSFET Q1 is charged mainly through the first resistor R1 and the first capacitor C1, so that it can start up quickly. Finally, the first resistor R1, the nineteenth resistor R19 and the third resistor R3 are used to achieve balance.
[0032] When the first MOSFET Q1 is turned off, its gate discharges mainly through the first capacitor C1, the first diode D1, and the second resistor R2, where R2 is the discharge resistor. Figure 1 As shown.
[0033] The low-voltage side drive and discharge circuit of the U-phase drive circuit includes a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a second MOSFET Q2, a third diode D3, a fourth diode D4, a second capacitor C2, and a twentieth resistor R20.
[0034] One end of the fourth resistor R4 and the fifth resistor R5 are connected together and connected to the control terminal LOU. The control terminal LOU is connected to the low-voltage side output of the U phase of the driver chip and is used to control the conduction and turn-off of the second MOSFET Q2.
[0035] In this embodiment, the second MOS transistor Q2 is, for example, an N-type GAN MOS transistor.
[0036] The other end of the fifth resistor R5 is connected to the negative terminal of the third diode D3; the positive terminal of the third diode D3, the other end of the fourth resistor R4, the second capacitor C2, and one end of the twentieth resistor R20 are connected.
[0037] The other end of the second capacitor C2 and the twentieth resistor R20 are connected, and are connected to the gate terminal of the second MOSFET Q2 and one end of the sixth resistor R6; the other end of the sixth resistor R6 is connected to the source terminal of the second MOSFET Q2.
[0038] The second capacitor C2 and the twentieth resistor R20 are newly added capacitors and resistors, and they are connected in parallel.
[0039] The fourth resistor R4 is obtained by reducing the resistance of the original voltage divider resistor R4' (e.g., Figure 2 The new voltage divider resistors obtained (as shown) have a sum of the resistance values of the fourth resistor R4 and the twentieth resistor R20, which is equal to the resistance value of the original voltage divider resistors.
[0040] The original voltage divider resistor R4' had a resistance in the kiloohm range, such as 3KΩ, and R4' was 8-12 times the resistance of the new voltage divider resistor. Therefore, the resistance of the new voltage divider resistor (i.e., the fourth resistor R4) is only in the hundred-ohm range, and the resistance is significantly reduced.
[0041] At the instant the second MOSFET Q2 is turned on, the gate of the second MOSFET Q2 is charged mainly through the fourth resistor R4 and the second capacitor C2, enabling it to start up quickly. Finally, the fourth resistor R4, the twentieth resistor R20 and the sixth resistor R6 are used to achieve balance.
[0042] When the second MOSFET Q2 is turned off, its gate discharges mainly through the second capacitor C2, the third diode D3, and the fifth resistor R5. The fifth resistor R5 is the discharge resistor. Figure 1 As shown.
[0043] The drive circuits for phases V and W are identical in structure to those for phase U, and will be described in detail below.
[0044] The high-voltage side drive and discharge circuit of the V-phase drive circuit includes the seventh resistor R7, the eighth resistor R8, the ninth resistor R9, the third MOSFET Q3, the fifth diode D5, the sixth diode D6, the third capacitor C3, and the twenty-first resistor R21.
[0045] One end of the seventh resistor R7 and the eighth resistor R8 are connected and connected to the control terminal HOV. The control terminal HOV is connected to the high-voltage side output of the V phase of the driver chip and is used to control the conduction and turn-off of the third MOSFET Q3.
[0046] In this embodiment, the third MOS transistor Q3 is, for example, an N-type GAN MOS transistor.
[0047] The other end of the eighth resistor R8 is connected to the negative terminal of the fifth diode D5; the positive terminal of the fifth diode D5, the other end of the seventh resistor R7, the third capacitor C3, and one end of the twenty-first resistor R21 are connected.
[0048] The third capacitor C3 and the other end of the twenty-first resistor R21 are connected, and are connected to the gate terminal of the third MOSFET Q3 and one end of the ninth resistor R9; the other end of the ninth resistor R9 is connected to the source terminal of the third MOSFET Q3.
[0049] The third capacitor C3 and the twenty-first resistor R21 are newly added capacitors and resistors, and they are connected in parallel.
[0050] The seventh resistor R7 is obtained by reducing the resistance of the original voltage divider resistor R7' (e.g., Figure 2 The new voltage divider resistor obtained is shown in the figure, and the sum of the resistance values of the seventh resistor R7 and the twenty-first resistor R21 is equal to the resistance value of the original voltage divider resistor.
[0051] The original voltage divider resistor R7' had a resistance in the kiloohm range, such as 3KΩ, and R7' was 8-12 times the resistance of the new voltage divider resistor. Therefore, the resistance of the new voltage divider resistor (i.e., the seventh resistor R7) is only in the hundred-ohm range, and the resistance is significantly reduced.
[0052] At the moment when the third MOSFET Q3 is turned on, the gate of Q3 is charged mainly through the seventh resistor R7 and the third capacitor C3, enabling it to start up quickly. Finally, the seventh resistor R7, the twenty-first resistor R21 and the ninth resistor R9 are used to achieve balance.
[0053] When the third MOSFET Q3 is turned off, its gate discharges mainly through the third capacitor C3, the fifth diode D5, and the eighth resistor R8. The eighth resistor R8 is the discharge resistor. Figure 1 As shown.
[0054] The low-voltage side drive and discharge circuit of the V-phase drive circuit includes the tenth resistor R10, the eleventh resistor R11, the twelfth resistor R12, the fourth MOSFET Q4, the seventh diode D7, the eighth diode D8, the fourth capacitor C4, and the twenty-second resistor R22.
[0055] One end of the tenth resistor R10 and the eleventh resistor R11 are connected and connected to the control terminal LOV. The control terminal LOV is connected to the low-voltage side output of the V phase of the driver chip and is used to control the conduction and turn-off of the fourth MOSFET Q4.
[0056] In this embodiment, the fourth MOS transistor Q4 is, for example, an N-type GAN MOS transistor.
[0057] The other end of the eleventh resistor R11 is connected to the negative terminal of the seventh diode D7; the positive terminal of the seventh diode D7, the other end of the tenth resistor R10, the fourth capacitor C4, and one end of the twenty-second resistor R22 are connected.
[0058] The fourth capacitor C4 and the other end of the twenty-second resistor R22 are connected to the gate terminal of the fourth MOSFET Q4 and one end of the twelfth resistor R12; the other end of the twelfth resistor R12 is connected to the source terminal of the fourth MOSFET Q4.
[0059] The fourth capacitor C4 and the twenty-second resistor R22 are newly added capacitors and resistors, and they are connected in parallel.
[0060] The tenth resistor R10 is obtained by reducing the resistance value of the original voltage divider resistor R10' (e.g., Figure 2 The new voltage divider resistors obtained (as shown) have a sum of the resistance values of the tenth resistor R10 and the twenty-second resistor R22, which is equal to the resistance value of the original voltage divider resistors.
[0061] The original voltage divider resistor R10' had a resistance in the kiloohm range, such as 3KΩ, and R10' was 8-12 times the resistance of the new voltage divider resistor. Therefore, the resistance of the new voltage divider resistor (i.e., the tenth resistor R10) is only in the hundred-ohm range, and the resistance is significantly reduced.
[0062] At the moment when the fourth MOSFET Q4 is turned on, the gate of Q4 is charged mainly through the tenth resistor R10 and the fourth capacitor C4, enabling it to start up quickly. Finally, the balance is achieved through the tenth resistor R10, the twenty-second resistor R22 and the twelfth resistor R12.
[0063] When the fourth MOSFET Q4 is turned off, its gate discharges mainly through the fourth capacitor C4, the seventh diode D7, and the eleventh resistor R11. The eleventh resistor R11 is the discharge resistor. Figure 1 As shown.
[0064] The high-voltage side drive and discharge circuit of the W-phase drive circuit includes the thirteenth resistor R13, the fourteenth resistor R14, the fifteenth resistor R15, the fifth MOSFET Q5, the ninth diode D9, the tenth diode D10, the fifth capacitor C5, and the twenty-third resistor R23.
[0065] One end of the thirteenth resistor R13 and the fourteenth resistor R14 are connected and connected to the control terminal HOW. The control terminal HOW is connected to the high-voltage side output of the W phase of the driver chip and is used to control the conduction and turn-off of the fifth MOSFET Q5.
[0066] In this embodiment, the fifth MOS transistor Q5 is, for example, an N-type GAN MOS transistor.
[0067] The other end of the fourteenth resistor R14 is connected to the negative terminal of the ninth diode D9; the positive terminal of the ninth diode D9, the other end of the thirteenth resistor R13, the fifth capacitor C5, and one end of the twenty-third resistor R23 are connected.
[0068] The fifth capacitor C5 and the other end of the twenty-third resistor R23 are connected to the gate terminal of the fifth MOSFET Q5 and one end of the fifteenth resistor R15; the other end of the fifteenth resistor R15 is connected to the source terminal of the fifth MOSFET Q5.
[0069] The fifth capacitor C5 and the twenty-third resistor R23 are newly added capacitors and resistors, and they are connected in parallel.
[0070] The thirteenth resistor R13 is obtained by reducing the resistance of the original voltage divider resistor R13' (e.g., Figure 2 The new voltage divider resistors obtained (as shown) have a sum of the resistance values of the thirteenth resistor R13 and the twenty-third resistor R23, which is equal to the resistance value of the original voltage divider resistors.
[0071] The original voltage divider resistor R13' had a resistance in the kiloohm range, such as 3KΩ, and R13' was 8-12 times the resistance of the new voltage divider resistor. Therefore, the resistance of the new voltage divider resistor (i.e., the thirteenth resistor R13) is only in the hundred-ohm range, and the resistance is significantly reduced.
[0072] At the moment when the fifth MOSFET Q5 is turned on, the gate of Q5 is charged mainly through the thirteenth resistor R13 and the fifth capacitor C5, enabling it to start up quickly. Finally, the balance is achieved through the thirteenth resistor R13, the twenty-third resistor R23 and the fifteenth resistor R15.
[0073] When the fifth MOSFET Q5 is turned off, its gate discharges mainly through the fifth capacitor C5, the ninth diode D9, and the fourteenth resistor R14. The fourteenth resistor R14 is the discharge resistor. Figure 1 As shown.
[0074] The low-voltage side drive and discharge circuit of the W-phase drive circuit includes the sixteenth resistor R16, the seventeenth resistor R17, the eighteenth resistor R18, the sixth MOSFET Q6, the eleventh transistor D11, the tenth diode D12, the sixth capacitor C6, and the twenty-fourth resistor R24.
[0075] One end of the sixteenth resistor R16 and the seventeenth resistor R17 are connected and connected to the control terminal LOW. The control terminal LOW is connected to the low-voltage side output of the W phase of the driver chip and is used to control the conduction and turn-off of the sixth MOSFET Q6.
[0076] In this embodiment, the sixth MOS transistor Q6 is, for example, an N-type GAN MOS transistor.
[0077] The other end of the seventeenth resistor R17 is connected to the negative terminal of the eleventh transistor D11; the positive terminal of the eleventh transistor D11, the other end of the sixteenth resistor R16, the sixth capacitor C6, and one end of the twenty-fourth resistor R24 are connected.
[0078] The sixth capacitor C6 and the other end of the twenty-fourth resistor R24 are connected to the gate terminal of the sixth MOSFET Q6 and one end of the eighteenth resistor R18; the other end of the eighteenth resistor R18 is connected to the source terminal of the sixth MOSFET Q6.
[0079] The sixth capacitor C6 and the twenty-fourth resistor R24 are newly added capacitors and resistors, and they are connected in parallel.
[0080] The sixteenth resistor R16 is obtained by reducing the resistance of the original voltage divider resistor R16' (e.g., Figure 2 The new voltage divider resistors obtained (as shown) have a sum of the resistance values of the sixteenth resistor R16 and the twenty-fourth resistor R24, which is equal to the resistance value of the original voltage divider resistors.
[0081] The original voltage divider resistor R16' had a resistance in the kiloohm range, such as 3KΩ, and R16' was 8-12 times the resistance of the new voltage divider resistor. Therefore, the resistance of the new voltage divider resistor (i.e., the sixteenth resistor R16) is only in the hundred-ohm range, and the resistance is significantly reduced.
[0082] At the moment when the sixth MOSFET Q6 is turned on, the gate of Q6 is charged mainly through the sixteenth resistor R16 and the sixth capacitor C6, enabling it to start up quickly. Finally, the balance is achieved through the sixteenth resistor R16, the twenty-fourth resistor R24 and the eighteenth resistor R18.
[0083] When the sixth MOSFET Q6 is turned off, its gate discharges mainly through the sixth capacitor C6, the eleventh diode D11, and the seventeenth resistor R17. The seventeenth resistor R17 is the discharge resistor. Figure 1 As shown.
[0084] The existing drive circuits have slow turn-on and turn-off speeds, which can cause damage to the MOSFET during the turn-on and turn-off process. Specifically, when the switching speed is slow, the time spent in the amplification region of the MOSFET made of N-type gallium nitride (GaN) material is longer. The resistance in the amplification region is relatively high, the heat generation is more severe, and the GaN MOSFET is more likely to be damaged.
[0085] The newly designed drive circuit adds an accelerating capacitor. When the MOS is driven and turned off, it is first accelerated through the capacitor (because the resistance of the capacitor itself is relatively small, the driving and turning-off voltages of the MOS are first charged or discharged through the capacitor when the MOS is turned on and off), thereby effectively increasing the MOS's turn-on and turn-off speed and ensuring the reliability of the MOS.
[0086] The inverter drive circuit in this embodiment can effectively accelerate the turn-on and turn-off of the MOS and increase the reliability of the MOS.
[0087] Example 2 This embodiment 2 describes a frequency converter to solve the problem of excessively long drive time and easy damage to MOSFETs in current high-efficiency low-voltage MOSFETs. Specifically, the frequency converter in this embodiment includes a control module, a power supply module, a communication module, a sampling feedback module, and a drive module, such as... Figure 3 As shown in the diagram. The communication module receives external signal input and controls the inverter's shutdown, startup, and speed; the sampling feedback module samples the inverter's output current and bus voltage, feeding them back to the control module to provide current protection, voltage protection, etc.; and the drive module provides the compressor's three-phase output voltage.
[0088] In this embodiment 2, the drive module adopts the frequency converter drive circuit described in embodiment 1 above.
[0089] Example 3 This embodiment 3 describes a compressor that uses a frequency converter as described in embodiment 2 above.
[0090] Of course, the above description is only a preferred embodiment of the present utility model. The present utility model is not limited to the above-described embodiments. It should be noted that any equivalent substitutions or obvious modifications made by those skilled in the art under the guidance of this specification fall within the scope of this specification and should be protected by the present utility model.
Claims
1. A frequency converter drive circuit, comprising three-phase drive circuits of U, V, and W; wherein each phase drive circuit comprises a high-voltage side drive and discharge circuit and a low-voltage side drive and discharge circuit; The control terminal of the high-voltage side / low-voltage side drive and discharge circuit is used to connect to the high-voltage side / low-voltage side output of the driver chip, and is used to control the conduction and turn-off of the MOS transistor in the high-voltage side / low-voltage side drive and discharge circuit. Its features are, The high-voltage / low-voltage driving and discharging circuit is based on the original high-voltage / low-voltage driving and discharging circuit using a resistor voltage divider structure, by adding a capacitor and a resistor at the gate terminal of the MOS transistor. Among them, the newly added capacitors and resistors are set in parallel; at the same time, based on the original high-voltage / low-voltage side drive and discharge circuit using a resistor voltage divider structure, the resistance value of the original voltage divider resistor is reduced to obtain a new voltage divider resistor. The sum of the resistance values of the new voltage divider resistor and the newly added resistor is equal to the resistance value of the original voltage divider resistor.
2. The inverter drive circuit according to claim 1, characterized in that, The original voltage divider resistor has a resistance value that is 8-12 times that of the new voltage divider resistor.
3. The inverter drive circuit according to claim 1, characterized in that, The high-voltage side drive and discharge circuit of the U-phase drive circuit includes: The first resistor (R1), the second resistor (R2), the third resistor (R3), the first MOSFET (Q1), the first diode (D1), the second diode (D2), the first capacitor (C1), and the nineteenth resistor (R19). One end of the first resistor (R1) and the second resistor (R2) are connected together and connected to the control terminal (HOU). The other end of the second resistor (R2) is connected to the negative terminal of the first diode (D1); the positive terminal of the first diode (D1), the other end of the first resistor (R1), the first capacitor (C1), and one end of the nineteenth resistor (R19) are connected together. The other end of the first capacitor (C1) and the nineteenth resistor (R19) are connected to the gate terminal of the first MOSFET (Q1) and one end of the third resistor (R3); the other end of the third resistor (R3) is connected to the source terminal of the first MOSFET (Q1). The first capacitor (C1) and the nineteenth resistor (R19) are newly added capacitors and resistors, and they are connected in parallel. The first resistor (R1) is a new voltage divider obtained by reducing the resistance value of the original voltage divider resistor, and the sum of the resistance values of the first resistor (R1) and the nineteenth resistor (R19) is equal to the resistance value of the original voltage divider resistor.
4. The inverter drive circuit according to claim 1, characterized in that, The low-voltage side drive and discharge circuit of the U-phase drive circuit includes: The fourth resistor (R4), the fifth resistor (R5), the sixth resistor (R6), the second MOSFET (Q2), the third diode (D3), the fourth diode (D4), the second capacitor (C2), and the twentieth resistor (R20); One end of the fourth resistor (R4) and the fifth resistor (R5) are connected together and connected to the control terminal (LOU). The other end of the fifth resistor (R5) is connected to the negative terminal of the third diode (D3); the positive terminal of the third diode (D3), the other end of the fourth resistor (R4), the second capacitor (C2), and one end of the twentieth resistor (R20) are connected together. The other end of the second capacitor (C2) and the twentieth resistor (R20) are connected to the gate of the second MOSFET (Q2) and one end of the sixth resistor (R6); the other end of the sixth resistor (R6) is connected to the source terminal of the second MOSFET (Q2). The second capacitor (C2) and the twentieth resistor (R20) are newly added capacitors and resistors, and are connected in parallel; The fourth resistor (R4) is a new voltage divider obtained by reducing the resistance value of the original voltage divider resistor, and the sum of the resistance values of the fourth resistor (R4) and the twentieth resistor (R20) is equal to the resistance value of the original voltage divider resistor.
5. The inverter drive circuit according to claim 1, characterized in that, The high-voltage side drive and discharge circuit of the V-phase drive circuit includes: The seventh resistor (R7), the eighth resistor (R8), the ninth resistor (R9), the third MOSFET (Q3), the fifth diode (D5), the sixth diode (D6), the third capacitor (C3), and the twenty-first resistor (R21); One end of the seventh resistor (R7) and the eighth resistor (R8) are connected together and connected to the control terminal (HOV). The other end of the eighth resistor (R8) is connected to the negative terminal of the fifth diode (D5); the positive terminal of the fifth diode (D5), the other end of the seventh resistor (R7), the third capacitor (C3), and one end of the twenty-first resistor (R21) are connected. The other end of the third capacitor (C3) and the twenty-first resistor (R21) are connected to the gate of the third MOSFET (Q3) and one end of the ninth resistor (R9); the other end of the ninth resistor (R9) is connected to the source terminal of the third MOSFET (Q3). The third capacitor (C3) and the twenty-first resistor (R21) are newly added capacitors and resistors, and they are connected in parallel. The seventh resistor (R7) is a new voltage divider obtained by reducing the resistance value of the original voltage divider resistor, and the sum of the resistance values of the seventh resistor (R7) and the twenty-first resistor (R21) is equal to the resistance value of the original voltage divider resistor.
6. The inverter drive circuit according to claim 1, characterized in that, The low-voltage side drive and discharge circuit of the V-phase drive circuit includes: The tenth resistor (R10), the eleventh resistor (R11), the twelfth resistor (R12), the fourth MOSFET (Q4), the seventh diode (D7), the eighth diode (D8), the fourth capacitor (C4), and the twenty-second resistor (R22). One end of the tenth resistor (R10) and the eleventh resistor (R11) are connected together and connected to the control terminal (LOV). The other end of the eleventh resistor (R11) is connected to the negative terminal of the seventh diode (D7); the positive terminal of the seventh diode (D7), the other end of the tenth resistor (R10), the fourth capacitor (C4), and one end of the twenty-second resistor (R22) are connected together. The other end of the fourth capacitor (C4) and the twenty-second resistor (R22) are connected to the gate of the fourth MOSFET (Q4) and one end of the twelfth resistor (R12); the other end of the twelfth resistor (R12) is connected to the source terminal of the fourth MOSFET (Q4). The fourth capacitor (C4) and the twenty-second resistor (R22) are newly added capacitors and resistors, and they are connected in parallel. The tenth resistor (R10) is a new voltage divider obtained by reducing the resistance value of the original voltage divider resistor, and the sum of the resistance values of the tenth resistor (R10) and the twenty-second resistor (R22) is equal to the resistance value of the original voltage divider resistor.
7. The inverter drive circuit according to claim 1, characterized in that, The high-voltage side drive and discharge circuit of the W-phase drive circuit includes: The thirteenth resistor (R13), the fourteenth resistor (R14), the fifteenth resistor (R15), the fifth MOSFET (Q5), the ninth diode (D9), the tenth diode (D10), the fifth capacitor (C5), and the twenty-third resistor (R23). One end of the thirteenth resistor (R13) and the fourteenth resistor (R14) are connected together and connected to the control terminal (HOW). The other end of the fourteenth resistor (R14) is connected to the negative terminal of the ninth diode (D9); the positive terminal of the ninth diode (D9), the other end of the thirteenth resistor (R13), the fifth capacitor (C5), and one end of the twenty-third resistor (R23) are connected together. The other end of the fifth capacitor (C5) and the twenty-third resistor (R23) are connected to the gate of the fifth MOSFET (Q5) and one end of the fifteenth resistor (R15); the other end of the fifteenth resistor (R15) is connected to the source terminal of the fifth MOSFET (Q5). The fifth capacitor (C5) and the twenty-third resistor (R23) are newly added capacitors and resistors, and they are connected in parallel. The thirteenth resistor (R13) is a new voltage divider obtained by reducing the resistance value of the original voltage divider resistor, and the sum of the resistance values of the thirteenth resistor (R13) and the twenty-third resistor (R23) is equal to the resistance value of the original voltage divider resistor.
8. The inverter drive circuit according to claim 1, characterized in that, The low-voltage side drive and discharge circuit of the W-phase drive circuit includes: The sixteenth resistor (R16), the seventeenth resistor (R17), the eighteenth resistor (R18), the sixth MOSFET (Q6), the eleventh transistor (D11), the tenth diode (D12), the sixth capacitor (C6), and the twenty-fourth resistor (R24). One end of the sixteenth resistor (R16) and the seventeenth resistor (R17) are connected together and connected to the control terminal (LOW). The other end of the seventeenth resistor (R17) is connected to the negative terminal of the eleventh transistor (D11); the positive terminal of the eleventh transistor (D11), the other end of the sixteenth resistor (R16), the sixth capacitor (C6), and one end of the twenty-fourth resistor (R24) are connected together. The other end of the sixth capacitor (C6) and the twenty-fourth resistor (R24) are connected to the gate of the sixth MOSFET (Q6) and one end of the eighteenth resistor (R18); the other end of the eighteenth resistor (R18) is connected to the source terminal of the sixth MOSFET (Q6). The sixth capacitor (C6) and the twenty-fourth resistor (R24) are newly added capacitors and resistors, and they are connected in parallel; The sixteenth resistor (R16) is a new voltage divider obtained by reducing the resistance value of the original voltage divider resistor, and the sum of the resistance values of the sixteenth resistor (R16) and the twenty-fourth resistor (R24) is equal to the resistance value of the original voltage divider resistor.
9. A frequency converter, comprising a control module, a power supply module, a communication module, a sampling feedback module, and a drive module; characterized in that, The drive module employs the frequency converter drive circuit as described in any one of claims 1 to 8.
10. A compressor, characterized in that, The frequency converter described in claim 9 above is used.