Cabinet single-chip drive circuit and air conditioner

Abstract

The invention provides a cabinet single-chip driving circuit, and the circuit comprises a main control minimum system circuit which comprises a single MCU chip and comprises a plurality of pins, a current sampling port, and a bus voltage sampling port; the direct current fan driving circuit is connected with the main control minimum system circuit through a plurality of pins; the fan current sampling circuit is connected with the main control minimum system circuit through a current sampling port; the bus voltage detection circuit is connected with the main control minimum system circuit through a bus voltage sampling port; wherein loads in the main control minimum system circuit, the direct current fan driving circuit, the fan current sampling circuit and the bus voltage detection circuit are driven through the MCU chip. The main control minimum system circuit adopts a single MCU chip, loads of the direct current fan driving circuit, the fan current sampling circuit and the bus voltage detection circuit can be driven through the MCU chip, the technical problem that two chips need to be adopted in the technical problem is solved, the cost is lower, and the production efficiency is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioners, and in particular to a cabinet single-chip driving circuit and an air conditioner. Background Art

[0002] At present, the main control board of the cabinet air conditioner products is generally a main control board without integrated fan drive circuit (used with built-in drive DC fan). There are generally two MCUs (chips) on this main control board. One MCU is dedicated to driving the fan driver chip. The ground supply of this chip is a non-isolated hot ground (people cannot touch it); the other MCU is used to drive the wind sweeping motor, temperature sensing package circuit, display board communication, etc. The ground supply of this chip is an isolated cold ground (people can touch it).

[0003] Therefore, in the prior art, two chips are required on the main control board to drive different loads respectively, which results in high cost and low production efficiency.

[0004] Based on this, the applicant proposes a cabinet single-chip drive circuit and an air conditioner to solve the above technical problems. Summary of the invention

[0005] The problem solved by the present invention is that in the prior art, two chips are required to drive different loads respectively, which results in high cost and low production efficiency.

[0006] To solve the above problems, the present invention provides a cabinet single-chip drive circuit, including: a main control minimum system circuit, the main control minimum system includes a single MCU chip, the main control minimum system circuit includes multiple pins, a current sampling port and a bus voltage sampling port; a DC fan drive circuit, connected to the main control minimum system circuit through multiple pins; a fan current sampling circuit, connected to the main control minimum system circuit through the current sampling port; a bus voltage detection circuit, connected to the main control minimum system circuit through the bus voltage sampling port; wherein the loads in the main control minimum system circuit, the DC fan drive circuit, the fan current sampling circuit and the bus voltage detection circuit are driven by the MCU chip.

[0007] Compared with the existing technology, the technical effect that can be achieved by adopting this solution is: the main control minimum system circuit adopts a single MCU chip, and the MCU chip can be used to drive the load of the DC fan drive circuit, the fan current sampling circuit, and the bus voltage detection circuit, which solves the technical problem of needing to use two chips, with lower costs and higher production efficiency.

[0008] In this embodiment, the DC fan drive circuit includes: a drive chip; a PWM drive circuit, the PWM drive circuit is electrically connected to the main control minimum system circuit, and the PWM drive circuit is electrically connected to the drive chip; a voltage stabilizing circuit, one end of the voltage stabilizing circuit is electrically connected to the drive chip, and the other end of the voltage stabilizing circuit is grounded; a signal circuit, one end of the signal circuit is electrically connected to the main control minimum system circuit, and the other end of the signal circuit is electrically connected to the drive chip; a bootstrap circuit, one end of the bootstrap circuit is electrically connected to the drive chip, and the other end of the bootstrap circuit is electrically connected to the drive chip; a protection circuit, one end of the protection circuit is electrically connected to the drive chip, and the other end of the protection circuit is grounded; a phase current sampling circuit, and the phase current sampling circuit is electrically connected to the drive chip.

[0009] The technical effect after adopting this technical solution is that the DC fan drive circuit functions to enable the motor to drive the DC fan to rotate under the action of the control chip, the PWM drive circuit is a three-phase drive circuit so that the drive signal is stable and reliable; the voltage stabilizing circuit can stabilize the power supply voltage to ensure that the output voltage of the power supply voltage is at a stable value; the signal circuit uses a series of components to filter, limit current and prevent static electricity, so as to achieve the purpose of signal transmission without impurities, the bootstrap circuit is used to drive the high-side switch circuit, and provides the required drive voltage through charging and discharging to ensure that the bus voltage is clean; the protection circuit can protect the circuit when it is short-circuited, and protect the drive chip.

[0010] In this embodiment, the fan current sampling circuit is connected to the phase current sampling circuit, and the fan current sampling circuit includes: a first resistor and a second resistor arranged between the input voltage and the output voltage and arranged in series; a first capacitor and a second capacitor arranged in parallel, the first capacitor is also connected in parallel with a first protection resistor, the first capacitor and the second capacitor play a filtering role, and one end of the first capacitor is grounded; a diode A and a diode B are arranged in series, the diode A is also connected in parallel with a second protection resistor, one end of the diode B is grounded, and one end of the diode A is connected to +5V.

[0011] The technical effect after adopting this technical solution is that the fan current sampling circuit can specifically adopt the above-mentioned components. Through the action of the above-mentioned components, the current of the U phase and the V phase can be sampled and converted into a voltage signal, which is then received by the MCU. It can accurately identify the speed, torque, and position of the motor, thereby controlling the motor to achieve the purpose of precise control.

[0012] In this embodiment, the bus voltage detection circuit includes: a resistor group arranged between the input voltage and the output voltage and arranged in series; a third resistor arranged in parallel with the resistor group; a diode C connected in parallel with the third resistor, the diode C prevents sudden high-level interference signals and protects the MCU chip; a third capacitor is arranged in parallel with the third resistor, and the third capacitor plays a filtering role; one end of the third capacitor is grounded, and one end of the diode C is connected to +5V.

[0013] The technical effect after adopting this technical solution is that, through the above-mentioned components, this circuit can monitor the bus voltage so that the MCU can reliably control the fan. The capacitor can filter to ensure that the voltage detection signal is interference-free and the signal is stable, while the diode prevents sudden high-level interference signals and can protect the chip.

[0014] In this embodiment, the driver chip is Silan Micro's fan IPM.

[0015] In this embodiment, the PWM driving circuit includes an RC filtering circuit formed by using an average resistor for the upper and lower bridges of the three phases U, V, and W and connecting an average capacitor in series to stabilize the driving signal.

[0016] The technical effect after adopting this technical solution is that the PWM drive circuit is an RC filter circuit, and the drive signal can be made stable and reliable through the above components.

[0017] In this embodiment, the voltage stabilizing circuit includes: using electrolytic capacitors for voltage stabilization and filtering; a voltage stabilizing diode connected in parallel to the electrolytic capacitor plays an overvoltage protection role; a fourth capacitor and a fifth capacitor connected in parallel to the voltage stabilizing diode play a power supply filtering role.

[0018] The technical effect after adopting this technical solution is that the voltage stabilizing circuit adopts the above components to stabilize the power supply voltage, and the stable power supply voltage ensures that the output voltage of the power supply voltage is at a stable value.

[0019] In this embodiment, the signal circuit includes: a sixth capacitor and a seventh capacitor arranged in parallel, the sixth capacitor and the seventh capacitor play a filtering role; a fourth resistor and a fifth resistor arranged between the input voltage and the output voltage, the fourth resistor and the fifth resistor play a current limiting role; one end of the sixth capacitor is grounded, and one end of the fifth resistor is connected to +5V.

[0020] The technical effect after adopting this technical solution is that the signal circuit uses the above components to filter, limit current and prevent static electricity, so as to achieve the purpose of signal transmission without impurities.

[0021] In this embodiment, the protection circuit includes: a sixth resistor and a seventh resistor that play a role of voltage division and current limiting; a seventh capacitor that is arranged in parallel on the sixth resistor, and the seventh capacitor plays a filtering role; a sampling resistor connected to one end of the seventh resistor; wherein one end of the sampling resistor is grounded, and one end of the protection circuit is connected to the driving chip.

[0022] The technical effect after adopting this technical solution is that the protection circuit can protect the driver chip when the circuit is short-circuited.

[0023] An air conditioner comprises the cabinet single-chip driving circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a structural schematic diagram of a cabinet single-chip drive circuit of the present invention;

[0025] Figure 2 for Figure 1 A magnified schematic diagram of part A;

[0026] Figure 3 for Figure 1 A magnified schematic diagram of part C;

[0027] Figure 4 for Figure 1 An enlarged schematic diagram of part D in the middle;

[0028] Figure 5 for Figure 1 A magnified schematic diagram of part B;

[0029] Figure 6 for Figure 5 Schematic diagram of the power supply circuit of the IPM;

[0030] Figure 7 for Figure 5 Schematic diagram of PWM drive circuit;

[0031] Figure 8 for Figure 5 Schematic diagram of the signal circuit;

[0032] Fig. 9 for Figure 5 Schematic diagram of the protection circuit;

[0033] Fig.10 for Figure 5 Schematic diagram of the bootstrap circuit;

[0034] Fig.11 for Figure 5 Schematic diagram of the phase current sampling circuit of the IPM;

[0035] Fig.12 for Figure 5 Schematic diagram of Zhongshilan Micro's fan IPM. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0037] A cabinet single chip drive circuit, such as Figure 1-12 As shown, it includes: a main control minimum system circuit, the main control minimum system includes a single MCU chip, the main control minimum system circuit includes multiple pins, a current sampling port and a bus voltage sampling port; a DC fan drive circuit, connected to the main control minimum system circuit through multiple pins; a fan current sampling circuit, connected to the main control minimum system circuit through the current sampling port; a bus voltage detection circuit, connected to the main control minimum system circuit through the bus voltage sampling port; wherein the loads in the main control minimum system circuit, the DC fan drive circuit, the fan current sampling circuit and the bus voltage detection circuit are driven by the MCU chip.

[0038] like Figure 1 , 2 As shown, the circuit at A in the figure is the main control minimum system circuit, which is essentially an MCU chip. The MCU chip of this circuit uses the Huada HC32L170 chip. The 6-way PWM output port uses a specific IO port, FO port, U-phase and V-phase current sampling ports, and bus voltage sampling ports also select specific IO ports, which cannot be selected randomly. There are many pins on it, among which VDC-AD, PWM-UN, PWM-VN, PWM-WN, PWM-UP, PWM-VP, and PWM-WP are connected at pins 25 to 31 respectively. F-FO, FIU-AD, and FIV-AD are connected at pins 16, 21, and 22 respectively. Its model is an XHSC microcontroller.

[0039] Among them, the current sampling port is set at pins 21 and 22, the bus voltage sampling port is set at pin 25, and the remaining pins 26 to 31 are connected to the PWM drive circuit.

[0040] The above-mentioned electrical connection method is adopted to achieve load driving of the DC fan drive circuit, the bus voltage detection circuit and the fan current sampling circuit through a single MCU chip.

[0041] The DC fan drive circuit includes: a drive chip; a PWM drive circuit, the PWM drive circuit is electrically connected to the main control minimum system circuit, and the PWM drive circuit is electrically connected to the drive chip; a voltage stabilizing circuit, one end of the voltage stabilizing circuit is electrically connected to the drive chip, and the other end of the voltage stabilizing circuit is grounded; a signal circuit, one end of the signal circuit is electrically connected to the main control minimum system circuit, and the other end of the signal circuit is electrically connected to the drive chip; a bootstrap circuit, one end of the bootstrap circuit is electrically connected to the drive chip, and the other end of the bootstrap circuit is electrically connected to the drive chip; a protection circuit, one end of the protection circuit is electrically connected to the drive chip, and the other end of the protection circuit is grounded; a phase current sampling circuit, and the phase current sampling circuit is electrically connected to the drive chip.

[0042] like Figure 1 , Figure 5 As stated in Figure 1 The circuit diagram at B in the figure uses a driver chip, which is Silan Micro's fan IPM, and has many pins. Pins 12, 13, 17, 18, 22, and 23 are connected to pins 26 to 31 on the MCU chip respectively. The DC fan drive circuit is composed of multiple circuit parts, so that the DC fan can be controlled by a single MCU chip to achieve the purpose of controlling the fan.

[0043] The fan current sampling circuit is connected to the phase current sampling circuit, and the fan current sampling circuit includes: a first resistor and a second resistor arranged between the input voltage and the output voltage and arranged in series; a first capacitor and a second capacitor arranged in parallel, the first capacitor is also connected in parallel with a first protection resistor, the first capacitor and the second capacitor play a filtering role, and one end of the first capacitor is grounded; a diode A and a diode B are arranged in series, the diode A is also connected in parallel with a second protection resistor, one end of the diode B is grounded, and one end of the diode A is connected to +5V.

[0044] like Figure 1 D in Figure 4 As shown in the figure, this circuit designs a current sampling circuit without an op amp. The circuit is simple and reliable. By sampling the current of the U phase and the V phase and converting it into a voltage signal, the MCU receives it and accurately identifies the speed, torque, and position of the motor, thereby controlling the motor to achieve the purpose of precise control.

[0045] The above-mentioned first resistor and second resistor include R19, R21, R23, and R25 in the figure; the first capacitor and the second capacitor include C15 to C18 in the figure; the first protection resistor includes R22 and R26 in the figure; diode A and diode B include D1 to D4 in the figure; and the second protection resistor includes R20 and R24 in the figure.

[0046] Collect U-phase and V-phase current and voltage, and calculate the fan current sampling:

[0047]

[0048]

[0049] Among them, R19 = 510Ω; R20 = 510Ω; R22 = 20KΩ; R21 = 510Ω;

[0050] U t is the voltage between D1 and D2.

[0051] U out =0.481U in +2.41

[0052] Amplification factor 0.481, bias voltage 2.41V.

[0053] In this circuit, resistors R19, R20, R21, R23, R24, and R25 must be 510Ω, and R22 and R26 must be 20KΩ; capacitors C15, C16, C17, and C18 act as filters, with C15 and C17 using 101 and C16 and C18 using 102; D1, D2, D3, and D4 use IN4148 for protection.

[0054] The bus voltage detection circuit includes: a resistor group arranged between the input voltage and the output voltage and arranged in series; a third resistor arranged in parallel with the resistor group; a diode C connected in parallel with the third resistor, diode C prevents sudden high-level interference signals and protects the MCU chip; a third capacitor is arranged in parallel with the third resistor, and the third capacitor plays a filtering role; one end of the third capacitor is grounded, and one end of the diode C is connected to +5V.

[0055] like Figure 1 In the C Figure 3 As shown, this circuit monitors the bus voltage so that the MCU can reliably control the fan.

[0056] The above-mentioned resistor group includes R28-R31 in the figure; the above-mentioned third resistor includes R27 in the figure; the above-mentioned diode C includes D5 in the figure; and the above-mentioned third capacitor includes C19 in the figure.

[0057] Among them, R31, R30, R29, and R28 all use 1206 packages, and the resistance value is 182KΩ. R27 uses a 0805 package 5.1KΩ resistor; the role of D5 is to prevent sudden high-level interference signals, clamp the voltage below 5.7V, and protect the chip; the role of C19 is filtering to ensure that the voltage detection signal is free of interference and the signal is stable.

[0058] The driver chip is Silan Micro's fan IPM.

[0059] The PWM drive circuit includes an averaging resistor for the upper and lower bridges of the three phases U, V, and W, and an averaging capacitor in series to form an RC filter circuit to stabilize the drive signal.

[0060] Figure 7 In the 6-way PWM drive circuit, the upper and lower bridges of the three phases U, V, and W all use resistors R1, R2, R3, R4, R5, and R6, all with a resistance of 100Ω, and capacitors C1, C2, C3, C4, C5, and C6, all with a capacitance of 331, to form an RC filter circuit, making the drive signal stable and reliable.

[0061] The voltage stabilizing circuit includes: using electrolytic capacitors for voltage stabilization and filtering; a voltage stabilizing diode connected in parallel to the electrolytic capacitor plays an overvoltage protection role; a fourth capacitor and a fifth capacitor connected in parallel to the voltage stabilizing diode play a power supply filtering role.

[0062] Among them, the above-mentioned components in the figure include the electrolytic capacitor E1, the voltage regulator diode ZD1, and the fourth capacitor and the fifth capacitor C7 and C8.

[0063] The power supply circuit of IPM adopts E1 (100uF) voltage regulator filter, and ZD1 voltage regulator diode is overvoltage protection; C7 and C8 are equipped with 104 chip capacitors to play the role of power supply filtering. This combination makes the power supply voltage of IPM stable and the filtering effect is good.

[0064] The signal circuit includes: a sixth capacitor and a seventh capacitor arranged in parallel, the sixth capacitor and the seventh capacitor play a filtering role; a fourth resistor and a fifth resistor arranged between the input voltage and the output voltage, the fourth resistor and the fifth resistor play a current limiting role; one end of the sixth capacitor is grounded, and one end of the fifth resistor is connected to +5V.

[0065] Among them, in the figure, the sixth and seventh capacitors of the above components are C9 and C10; the fourth and fifth resistors are R7 and R8.

[0066] FO signal circuit, C9 and C10 play a filtering role, and the capacitance value is particular, C9 uses 222, C10 uses 102, resistors R7 and R8 have current limiting and anti-static effects, and the resistance value is particular, R7 uses 1.5KΩ, and R8 uses 100Ω.

[0067] It also includes a bootstrap circuit, which is used to drive the high-side switch circuit. The required driving voltage is provided by charging and discharging. U phase uses E2 (100uF) with C11 (104), V phase uses E3 (100uF) with C12 (104), and W phase uses E4 (100uF) with C13 (104). The electrolytic capacitors here are all 100uF, and the chip capacitors are 104 to achieve stable filtering and reliable charging and discharging effects; CRV1 is the filter capacitor on the 310V bus. It filters when the 310V enters the IPM to ensure that the bus voltage is clean.

[0068] The protection circuit includes: a sixth resistor and a seventh resistor that play a role of voltage division and current limiting; a seventh capacitor that is arranged in parallel on the sixth resistor, and the seventh capacitor plays a filtering role; a sampling resistor connected to one end of the seventh resistor; wherein one end of the sampling resistor is grounded, and one end of the protection circuit is connected to the driving chip.

[0069] The sixth resistor and the seventh resistor include the resistors R14 and R13 as shown in the figure; the seventh capacitor includes the capacitor C14 as shown in the figure, the sampling resistors are R15-R18, the IPM short-circuit protection circuit, the network port SC is connected to the IPM pin 10, when the total current exceeds the typical value of 1.74A, that is, the network port SC detects that the voltage is 0.48V, then the IPM short-circuit protection trigger voltage value is reached, and the IPM enters short-circuit protection, the resistors R15, R16, R17, R18 are the sampling resistors of the total current, and the resistance value selection has requirements, and a 1.6Ω is selected with 3 1Ω resistors; R13 and R14 form a voltage divider and current limiting circuit, but here R13 can be selected not to be installed or adjusted to other resistance values, which is mainly related to the IPM short-circuit protection trigger voltage value; C14 plays a filtering role;

[0070] A phase current sampling circuit is electrically connected to the driving chip.

[0071] The components of the phase current sampling circuit of the IPM, R9, R10, R11, R12 are sampling resistors;

[0072] An air conditioner includes a cabinet single-chip driving circuit.

[0073] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A cabinet single-chip drive circuit, characterized in that: include: A main control minimum system circuit, wherein the main control minimum system includes a single MCU chip, and the main control minimum system circuit includes a plurality of pins, a current sampling port, and a bus voltage sampling port; A DC fan driving circuit is connected to the main control minimum system circuit through a plurality of the pins; A fan current sampling circuit is connected to the main control minimum system circuit through the current sampling port; A bus voltage detection circuit, connected to the main control minimum system circuit through the bus voltage sampling port; Among them, the loads in the main control minimum system circuit, the DC fan drive circuit, the fan current sampling circuit and the bus voltage detection circuit are driven by the MCU chip.

2. A cabinet single chip drive circuit according to claim 1, characterized in that: The DC fan drive circuit comprises: Driver chip; A PWM drive circuit, wherein the PWM drive circuit is electrically connected to the master control minimum system circuit, and the PWM drive circuit is electrically connected to the drive chip; A voltage stabilizing circuit, one end of which is electrically connected to the driving chip, and the other end of which is grounded; a signal circuit, one end of which is electrically connected to the master control minimum system circuit, and the other end of which is electrically connected to the driver chip; A bootstrap circuit, one end of which is electrically connected to the driver chip, and the other end of which is electrically connected to the driver chip; A protection circuit, one end of which is electrically connected to the driving chip, and the other end of which is grounded; A phase current sampling circuit is electrically connected to the driving chip.

3. A cabinet single chip drive circuit according to claim 2, characterized in that: The fan current sampling circuit is connected to the phase current sampling circuit, and the fan current sampling circuit includes: a first resistor and a second resistor which are arranged between the input voltage and the output voltage and are arranged in series; A first capacitor and a second capacitor are arranged in parallel, the first capacitor is also connected in parallel with a first protection resistor, the first capacitor and the second capacitor play a filtering role, and one end of the first capacitor is grounded; A diode A and a diode B are connected in series, and the diode A is also connected in parallel with a second protection resistor. One end of the diode B is grounded, and one end of the diode A is connected to +5V.

4. The cabinet single-chip drive circuit according to claim 2, characterized in that: The bus voltage detection circuit comprises: A resistor group is arranged between the input voltage and the output voltage and is arranged in series; A third resistor is arranged in parallel with the resistor group; A diode C connected in parallel with the third resistor, wherein the diode C prevents sudden high-level interference signals and protects the MCU chip; The third resistor is connected in parallel with a third capacitor, which plays a filtering role; one end of the third capacitor is grounded, and one end of the diode C is connected to +5V.

5. The cabinet single-chip drive circuit according to claim 2, characterized in that: The driver chip is Silan Micro's fan IPM.

6. A cabinet single chip drive circuit according to claim 2, characterized in that: The PWM driving circuit includes an RC filtering circuit formed by using an average resistor for the upper and lower bridges of the three phases U, V, and W and connecting an average capacitor in series to stabilize the driving signal.

7. The cabinet single-chip drive circuit according to claim 2, characterized in that: The voltage stabilizing circuit comprises: Adopt electrolytic capacitor for voltage stabilization and filtering; The voltage zener diode connected in parallel to the electrolytic capacitor plays an overvoltage protection role; The fourth capacitor and the fifth capacitor are connected in parallel to the voltage stabilizing diode to play a role in power supply filtering.

8. The cabinet single-chip drive circuit according to claim 2, characterized in that: The signal circuit comprises: The sixth capacitor and the seventh capacitor are connected in parallel, and the sixth capacitor and the seventh capacitor play a filtering role; A fourth resistor and a fifth resistor are arranged between the input voltage and the output voltage, and the fourth resistor and the fifth resistor play a current limiting role; One end of the sixth capacitor is grounded, and one end of the fifth resistor is connected to +5V.

9. The cabinet single-chip drive circuit according to claim 2, characterized in that: The protection circuit comprises: The sixth resistor and the seventh resistor play the role of voltage division and current limiting; A seventh capacitor is arranged in parallel with the sixth resistor, and the seventh capacitor plays a filtering role; a sampling resistor connected to one end of the seventh resistor; Wherein, one end of the sampling resistor is grounded, and one end of the protection circuit is connected to the driving chip.

10. An air conditioner, comprising a cabinet single-chip driving circuit as claimed in any one of claims 1 to 9.

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