Controller for multi-motor cooperative driving

Abstract

The utility model relates to the technical field of fan control, in particular to a controller for multi-motor cooperative driving, which comprises a step-down conversion circuit and a control circuit, the step-down conversion circuit is used for converting input alternating-current voltage into direct-current voltage and respectively supplying power to motors and the control circuit, the control circuit is internally provided with an MCU (Microprogrammed Control Unit) and a plurality of MOS (Metal Oxide Semiconductor) chips, the control circuit is powered by direct-current voltage and outputs PWM signals through the MCU to control on-off of the multiple MOS chips respectively, and then operation of the multiple motors is controlled. According to the utility model, a plurality of motors can be controlled by one controller, so that the cost is greatly reduced, the stability of the whole system is improved, convenience is provided for subsequent overhaul and maintenance, the joint adjustment and the controllability are improved, and limited resources can be better and fully utilized in applied devices and equipment for optimal distribution.

Description

Technical Field

[0001] The utility model relates to the technical field of fan control, and in particular to a controller for cooperative driving of multiple motors. Background Art

[0002] The EC motors currently used all have one control board for each machine. When multiple fans need to be controlled, they are either controlled by the host computer or by an additional control board. The control board of each fan has a communication module, and each motor needs to be connected by a signal line, which has poor cost and coordination. For example, in actual applications, refrigerators need to use multiple fans, such as condensing fans, evaporating fans, etc. At this time, each fan has a built-in control board, and these fans need another control board to work together. Utility Model Content

[0003] In order to solve the technical problems of low utilization rate and poor coordination of the control board in the prior art, the utility model proposes a controller for multi-motor coordinated drive, and its specific technical solution is as follows:

[0004] A controller for cooperative driving of multiple motors includes a step-down conversion circuit and a control circuit. The step-down conversion circuit is used to convert an input AC voltage into a DC voltage and supply power to the motor and the control circuit respectively. The control circuit is provided with an MCU and a plurality of MOS chips corresponding to the number of motors. The control circuit is powered by a DC voltage and outputs PWM signals through the MCU to control the on and off of the plurality of MOS chips respectively, thereby controlling the operation of the plurality of motors.

[0005] Furthermore, the step-down conversion circuit includes: a rectifier bridge, an isolated Flyback constant voltage and constant current control chip, and a switching power supply driver chip. The input 220V AC voltage is rectified into a 310V DC voltage after passing through the rectifier bridge. The rectified 310V DC voltage is sequentially stepped down by the isolated Flyback constant voltage and constant current control chip and the switching power supply driver chip to obtain 24V DC voltage and 5V DC voltage respectively, wherein the 24V DC voltage is used to power the motor and the control circuit, and the 5V DC voltage is used to power the MCU.

[0006] Furthermore, the step-down conversion circuit further includes: a transformer, a MOS tube, a resistor R6, an RCD absorption circuit, an absorption loop, a rectifier diode D1, a freewheeling inductor, and electrolytic capacitors C2, C4, and C5, and the transformer includes a main power supply winding, an output winding, and an auxiliary winding;

[0007] Pins 1 and 3 of the rectifier bridge are connected to input 220V AC voltage, pin 2 of the rectifier bridge is connected to the positive electrode of the electrolytic capacitor C4, pin 4 of the rectifier bridge is connected to the negative electrode of the electrolytic capacitor C4 and grounded, and pins 2 and 4 of the rectifier bridge output 310V DC voltage;

[0008] The rectifier bridge pin 2 is also connected to the HV pin of the isolated Flyback constant voltage and constant current control chip through the resistor R6 to provide a starting voltage for the Flyback constant voltage and constant current control chip;

[0009] The ground terminal of the isolated Flyback constant voltage and constant current control chip is connected to the S pole of the MOS tube;

[0010] The signal output pin of the isolated Flyback constant voltage and constant current control chip is connected to the G pole of the MOS tube;

[0011] The auxiliary winding is connected to the input terminal Vcc of the isolated Flyback constant voltage and constant current control chip to supply power to the isolated Flyback constant voltage and constant current control chip;

[0012] One end of the RCD absorption circuit and one end of the main power supply winding are connected to the 2nd foot of the rectifier bridge, and the other end and the other end of the main power supply winding are connected to the D pole of the MOS tube;

[0013] One end of the output winding is connected to the positive electrode of the rectifier diode D1 to output a 24V DC voltage. The negative electrode of the rectifier diode D1 is connected to the positive electrodes of the electrolytic capacitor C5 and the electrolytic capacitor C2. The other end of the output winding is connected to the negative electrodes of the electrolytic capacitor C5 and the electrolytic capacitor C2. The absorption circuit is connected in parallel with the rectifier diode D1. The two ends of the electrolytic capacitor C2 are connected to the two ends of the freewheeling inductor. The other two ends of the freewheeling inductor are connected to the output, and the output is a 24V DC voltage.

[0014] Furthermore, the RCD absorption circuit includes: resistors R3~R5, resistors R7~R8, capacitor C3 and diode D2, one end of the resistors R3~R5 and capacitor C3 are respectively connected to one end of the main power supply winding, and the other end of the resistors R3~R5 and capacitor C3 are connected in sequence; one end of the resistor R7 and the resistor R8 are connected and then connected to the cathode of the diode D2, the other end of the resistor R7 and the resistor R8 are respectively connected to the other end of the resistor R4 and the resistor R5, and the anode of the diode D2 is connected to the other end of the main power supply winding and then connected to the D pole of the MOS tube.

[0015] Furthermore, the absorption circuit includes: resistor R1, resistor R2 and capacitor C1, one end of the resistor RI and resistor R2 connected in parallel is connected to one end of the capacitor C1, and the other end of the parallel connection is connected to the positive electrode of the rectifier diode D1, and the other end of the capacitor C1 is connected to the positive electrode of the electrolytic capacitor C2.

[0016] Furthermore, the control circuit is also provided with a high-speed half-bridge driver chip, the power pin of the high-speed half-bridge driver chip is connected to the 24V DC voltage, and the PWM signal output by the MCU is processed by the dual high-speed half-bridge driver chips to control the on and off of multiple MOS chips.

[0017] Furthermore, the PWM signal output pin of the MCU is connected to the signal input pin of the dual high-speed half-bridge driver chip, and the control signal output pin of the high-speed half-bridge driver chip is respectively connected to the G pole pins of multiple MOS chips, the D pole pin of each MOS chip is connected to a 24V DC voltage, and the S pole pin of each MOS chip is connected to the coil of the corresponding motor.

[0018] The utility model can control multiple fans through one controller, which not only greatly reduces the cost, but also improves the stability of the overall system, provides convenience for subsequent inspection and maintenance, improves the coordination and controllability, and can better make full use of limited resources in the applied devices and equipment for optimal allocation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the flow of AC / DC voltage conversion and output of a controller for multi-motor cooperative driving according to an embodiment of the utility model;

[0020] Figure 2 It is a flow chart of AC / DC conversion output and signal output control of a controller for multi-motor cooperative driving according to an embodiment of the utility model;

[0021] Figure 3 It is a schematic diagram of a 220V step-down conversion circuit of a controller for multi-motor coordinated drive according to an embodiment of the utility model;

[0022] Figure 4 It is a schematic diagram of a control circuit of a controller for multi-motor cooperative driving according to an embodiment of the utility model. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and technical effect of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments of the specification.

[0024] like Figure 1 As shown, the controller of the embodiment of the utility model can cooperatively drive two EC motors. The controller includes a control circuit and a 220V step-down conversion circuit. The 220V step-down conversion circuit is used to convert the input 220V AC voltage into a DC voltage and output it to the control circuit and the two EC motors; the control circuit controls the operation of the two EC motors respectively through the PWM signal output by the MCU, and the MCU can also be externally connected to the UART communication serial port and the FG speed regulating valve, such as Figure 2 As shown, it not only reduces costs, but also expands functions, improves stability and reduces maintenance costs.

[0025] The 220V step-down conversion circuit includes a rectifier bridge, an isolated Flyback constant voltage and constant current control chip, and a switching power supply driver chip. A 220V AC voltage is input into the 220V step-down conversion circuit. The 220V AC voltage is rectified into a 310V DC voltage after passing through the rectifier bridge. The rectified 310V DC voltage is stepped down in turn through the isolated Flyback constant voltage and constant current control chip and the switching power supply driver chip to obtain 24V and 5V DC voltages, respectively. The 24V DC voltage is used to power the motor and the control circuit, and the 5V DC voltage is used to power the MCU.

[0026] Specifically, Figure 3 As shown, T1A, T2B and T3C are three windings of the same transformer, which are the main power supply winding, the output winding and the auxiliary winding respectively. The 220V AC input terminal is connected to the 1st and 3rd pins of the rectifier bridge BD1, the positive electrode of the electrolytic capacitor C4 is connected to the 2nd pin of the rectifier bridge, and the negative electrode is connected to the 4th pin of the rectifier bridge and grounded. Pin 2 of the rectifier bridge is connected to the HV pin of the isolated Flyback constant voltage and constant current control chip U through the resistor R6 to provide a starting voltage for the Flyback constant voltage and constant current control chip U. The ground terminal is connected to the S pole of the MOS tube Q1, the D pole of the MOS tube Q1 is connected to the 3 pin of the main power supply winding of the transformer, and the G pole of the MOS tube Q1 is connected to the PWM signal output pin of the chip U; the auxiliary winding pin 5 is connected to the input terminal Vcc of the chip U to power the chip U; the output winding pin 11 is connected to the positive pole of the diode D1, the negative pole of the diode D1 is connected to the positive pole of the electrolytic capacitors C5 and C2, the output winding pin 9 is connected to the negative pole of the electrolytic capacitors C5 and C2, the two ends of the electrolytic capacitor C2 are connected to the two ends of the inductor L1, and the other two ends of the inductor L1 are connected to the output.

[0027] The working principle of the step-down conversion circuit outputting 24V DC voltage is as follows: after 220V AC is input from pins 1 and 3 of the rectifier bridge BD1, 310V DC voltage Vbus is output from pins 2 and 4. The electrolytic capacitor C4 is used for filtering and energy storage to stabilize the voltage. The resistor R6 is used as a starting resistor to start the power chip when there is no energy stored in the auxiliary winding for the first time. The resistors R3, R4, R5, R7, R8, the capacitor C3 and the diode D2 form an RCD absorption circuit to absorb the resonant voltage spike when the MOS tube Q1 is turned off. 310 The V DC voltage Vbus flows through the transformer and reaches the switch MOS tube Q1. The control pin of the isolated Flyback constant voltage and constant current control chip U outputs a control signal to the G pole of the MOS tube Q1. The MOS tube Q1 is turned on, the auxiliary winding and the output winding of the transformer are charged, and the isolated Flyback constant voltage and constant current control chip U outputs a shutdown signal. The auxiliary winding and the output winding are discharged. At this time, the auxiliary winding can maintain the normal operation of the U chip, and the output winding 11 pin outputs 24V; the electrolytic capacitors C2 and C5 are used for filtering and energy storage to stabilize the voltage. The diode D1 is a rectifier diode to ensure unidirectional conduction. After the resistors RI and R2 are connected in parallel, they are connected in series with the capacitor C1 to form an absorption circuit in parallel with the diode D1. Its function is to suppress the peak voltage in the direction and cause damage to the insufficient withstand voltage of the diode D1. L1 is a freewheeling inductor to avoid sudden changes in the load current and play a role in smoothing the current.

[0028] The control circuit mainly includes a single-chip microcomputer MCU, a MOS chip, and a dual high-speed half-bridge driver chip. The PWM signal output by the MCU is processed by the dual high-speed half-bridge driver chip to control the shutdown of multiple MOS chips, thereby realizing the control of multiple motors.

[0029] Specifically, Figure 4 As shown, the PWM signal output pin of the MCU is connected to the signal input pins of the dual high-speed half-bridge driver chips U1 and U2, the control signal output pin of the high-speed half-bridge driver chip U1 is respectively connected to the G-pole pins of the MOS chips M1, M2, and M3, and the control signal output pin of the high-speed half-bridge driver chip U2 is respectively connected to the G-pole pins of the MOS chips M4, M5, and M6; the D-pole pin of the MOS chip is connected to the 24V DC voltage obtained by the 220V step-down conversion circuit, and the S-pole pin of the MOS chip is connected to the coil of the EC motor, and the high-speed operation of the EC motor is controlled by controlling the on and off of the above-mentioned MOS chips; each channel of the high-speed half-bridge driver chip has two outputs, has an internal dead time to avoid cross conduction and has thermal shutdown protection to ensure safety, and can achieve faster switching with smaller propagation delays, thereby improving the overall system efficiency.

[0030] The controller of the embodiment of the utility model only needs one controller to coordinately control multiple motors, and the controller can be placed separately from the motors, so that the waterproofness and maintenance convenience are greatly improved, and the communication only needs to be connected to this one controller.

[0031] The above is only a preferred implementation case of the utility model, and does not limit the utility model in any form. Although the implementation process of the utility model is described in detail above, for those familiar with the art, they can still modify the technical solutions recorded in the above examples, or replace some of the technical features therein with equivalents. All modifications and equivalent replacements made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. A controller for multi-motor coordinated driving, comprising a step-down conversion circuit and a control circuit, characterized in that: The step-down conversion circuit converts the input AC voltage into a DC voltage and supplies power to the motor and control circuit respectively. The control circuit is provided with an MCU and a plurality of MOS chips corresponding to the number of motors. The control circuit is powered by a DC voltage and controls the on and off of the plurality of MOS chips respectively through the MCU output PWM signals, thereby controlling the operation of the plurality of motors.

2. The controller according to claim 1, characterized in that: The step-down conversion circuit includes: a rectifier bridge, an isolated Flyback constant voltage and constant current control chip, and a switching power supply driver chip. The input 220V AC voltage is rectified into a 310V DC voltage after passing through the rectifier bridge. The rectified 310V DC voltage is sequentially stepped down by the isolated Flyback constant voltage and constant current control chip and the switching power supply driver chip to obtain 24V DC voltage and 5V DC voltage respectively, wherein the 24V DC voltage is used to power the motor and the control circuit, and the 5V DC voltage is used to power the MCU.

3. The controller according to claim 2, characterized in that: The step-down conversion circuit further includes: a transformer, a MOS tube, a resistor R6, an RCD absorption circuit, an absorption loop, a rectifier diode D1, a freewheeling inductor, and electrolytic capacitors C2, C4, and C5. The transformer includes a main power supply winding, an output winding, and an auxiliary winding. Pins 1 and 3 of the rectifier bridge are connected to input 220V AC voltage, pin 2 of the rectifier bridge is connected to the positive electrode of the electrolytic capacitor C4, pin 4 of the rectifier bridge is connected to the negative electrode of the electrolytic capacitor C4 and grounded, and pins 2 and 4 of the rectifier bridge output 310V DC voltage; The rectifier bridge pin 2 is also connected to the HV pin of the isolated Flyback constant voltage and constant current control chip through resistor R6; The ground terminal of the isolated Flyback constant voltage and constant current control chip is connected to the S pole of the MOS tube; The signal output pin of the isolated Flyback constant voltage and constant current control chip is connected to the G pole of the MOS tube; The auxiliary winding is connected to the input terminal Vc of the isolated Flyback constant voltage and constant current control chip; One end of the RCD absorption circuit and one end of the main power supply winding are connected to the 2nd foot of the rectifier bridge, and the other end and the other end of the main power supply winding are connected to the D pole of the MOS tube; One end of the output winding is connected to the positive electrode of the rectifier diode D1 to output a 24V DC voltage. The negative electrode of the rectifier diode D1 is connected to the positive electrodes of the electrolytic capacitor C5 and the electrolytic capacitor C2. The other end of the output winding is connected to the negative electrodes of the electrolytic capacitor C5 and the electrolytic capacitor C2. The absorption circuit is connected in parallel with the rectifier diode D1. The two ends of the electrolytic capacitor C2 are connected to the two ends of the freewheeling inductor. The other two ends of the freewheeling inductor are connected to the output, and the output is a 24V DC voltage.

4. The controller according to claim 3, characterized in that: The RCD absorption circuit includes: resistors R3~R5, resistors R7~R8, capacitor C3 and diode D2, one end of the resistors R3~R5 and capacitor C3 is respectively connected to one end of the main power supply winding, and the other end of the resistors R3~R5 and capacitor C3 is connected in sequence; one end of the resistor R7 and resistor R8 is connected and then connected to the cathode of the diode D2, the other end of the resistor R7 and resistor R8 is respectively connected to the other end of the resistor R4 and resistor R5, and the anode of the diode D2 is connected to the other end of the main power supply winding and then connected to the D pole of the MOS tube.

5. The controller according to claim 3, characterized in that: The absorption circuit includes: resistor R1, resistor R2 and capacitor C1, one end of the resistor R1 and resistor R2 connected in parallel is connected to one end of the capacitor C1, and the other end of the parallel connection is connected to the positive electrode of the rectifier diode D1, and the other end of the capacitor C1 is connected to the positive electrode of the electrolytic capacitor C2.

6. The controller according to claim 2, characterized in that: The control circuit is also provided with a high-speed half-bridge driver chip, the power pin of the high-speed half-bridge driver chip is connected to the 24V DC voltage, and the PWM signal output by the MCU is processed by the dual high-speed half-bridge driver chips to control the on and off of multiple MOS chips.

7. The controller according to claim 6, characterized in that: The PWM signal output pin of the MCU is connected to the signal input pin of the dual high-speed half-bridge driver chip, and the control signal output pin of the high-speed half-bridge driver chip is respectively connected to the G pole pins of multiple MOS chips, the D pole pin of each MOS chip is connected to a 24V DC voltage, and the S pole pin of each MOS chip is connected to the coil of the corresponding motor.

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