Wind system and motor assembly and control method thereof

Abstract

The application provides a wind system. The wind system comprises a master motor unit and a slave motor unit. The master motor unit comprises a master control unit, a master driving device and a master motor, the master driving device is configured to be controlled by the master control unit, and the master motor is configured to be driven by the master driving device. The slave motor unit comprises a slave driving device and a slave motor, the slave driving device is configured to be controlled by the master control unit, and the slave motor is configured to be driven by the slave driving device. The motor assembly of the application is beneficial to the control of the motor operation state, facilitates manufacturing, reduces faults, avoids resonance, saves costs and reduces electromagnetic interference.

Description

Technical Field

[0001] This application relates to air systems, and more particularly to motor components in air systems and methods for controlling them. Background Technology

[0002] In a ventilation system, indoor air entering the system exchanges heat with water in the system coils. The motor is a crucial component for achieving this heat exchange function. Therefore, there is a need for a motor assembly that is stable in operation, easy to manufacture, and cost-effective. Summary of the Invention

[0003] This application provides a wind system in which the arrangement of the motor assembly facilitates control of the motor's operating status, facilitates manufacturing, reduces malfunctions, avoids resonance, saves costs, and reduces electromagnetic interference.

[0004] According to one aspect of this application, the wind system of this application includes a main motor unit and a slave motor unit. The main motor unit includes a main control unit, a main drive device, and a main motor, wherein the main drive device is configured to be controlled by the main control unit. ， The master motor is configured to be driven by the master drive unit. The slave motor unit includes a slave drive unit and a slave motor, wherein the slave drive unit is configured to be controlled by the master control unit, and the slave motor is configured to be driven by the slave drive unit.

[0005] In the wind system described above, the main motor unit and the slave motor unit are physically separate motor units.

[0006] In the wind system described above, the main motor unit and the slave motor unit are configured to communicate with each other via a main motor I / O interface and a slave motor I / O interface.

[0007] In the wind system described above, the main control unit is configured to receive the operating status signal of the slave motor and control the operation of the slave motor according to the operating status signal of the slave motor.

[0008] In the wind system described above, the main control unit is configured to receive the operating parameters of the main motor and control the operation of the main motor according to the operating parameters of the main motor.

[0009] As described above, the main motor unit operates in a constant speed mode, a constant torque mode, or a constant power mode. The operating parameters of the main motor include its speed, the winding AC current, and the inverter voltage. The main control unit is configured to control the main motor's speed via the main drive device based on its speed, control its torque via the main drive device based on the winding AC current, and control its power via the main drive device based on the product of the winding AC current and the inverter voltage.

[0010] In the wind system described above, the master control unit is configured to issue control signals to control the rotational speed of the slave motor via the slave drive device.

[0011] In the wind system described above, the slave motor unit is configured to be controlled to operate in speed-following mode or speed-following mode and vibration-damping mode.

[0012] In the wind system described above, the main control unit is configured such that, when the slave motor unit is running in the speed following mode, the main control unit sends a control signal to control the slave motor to rotate at a specific speed through the slave drive device. The specific speed includes the same speed as the main motor, or a speed less than or greater than the main motor.

[0013] In the wind system described above, the main control unit (204) is configured to: receive and parse command signals received from an external control center to determine the ideal target speed of the main motor and the ideal target speed of the slave motor corresponding to the command signals, and determine whether the difference between the ideal target speed of the main motor and the ideal target speed of the slave motor and the resonance speed that causes the wind system to resonate reaches a predetermined vibration damping amount; if the difference between the ideal target speed of the main motor and the ideal target speed of the slave motor and the resonance speed reaches or exceeds the predetermined vibration damping amount, the main control unit (204) sets the ideal target speed of the main motor to the actual target speed of the main motor and sets the ideal target speed of the slave motor to the actual target speed of the slave motor; and if the difference between at least one of the ideal target speed of the main motor and the ideal target speed of the slave motor and the resonance speed does not reach the predetermined vibration damping amount, when the ideal target speed of the main motor is greater than or equal to the ideal target speed of the slave motor, the main control unit (204) sets the ideal target speed of the main motor to the actual target speed of the main motor and sets the ideal target speed of the slave motor to the actual target speed of the slave motor; and if the difference between at least one of the ideal target speed of the main motor and the ideal target speed of the slave motor and the resonance speed does not reach the predetermined vibration damping amount, the main control unit (204) sets the ideal target speed of the main motor to the actual target speed of the slave motor when the ideal target speed of the main motor is greater than or equal to the ideal target speed of the slave motor. When the motor reaches its ideal target speed, the main control unit (204) sets the first adjustment target speed of the main motor to the actual target speed of the main motor and sets the first adjustment target speed of the slave motor to the actual target speed of the slave motor. When the ideal target speed of the main motor is less than the ideal target speed of the slave motor, the main control unit (204) sets the second adjustment target speed of the main motor to the actual target speed of the main motor and sets the second adjustment target speed of the slave motor to the actual target speed of the slave motor. Wherein, the first adjustment target speed of the main motor = the ideal target speed of the main motor + n × predetermined vibration damping amount, the first adjustment target speed of the slave motor = the ideal target speed of the slave motor - n × predetermined vibration damping amount; and the second adjustment target speed of the main motor = the ideal target speed of the main motor - n × predetermined vibration damping amount, the second adjustment target speed of the slave motor = the ideal target speed of the slave motor + n × predetermined vibration damping amount; where n is selected from 2 or a positive integer greater than 2.

[0014] In the wind system described above, the main motor unit includes a power conversion unit, and the main control unit is configured to monitor the current output from the power conversion unit, and based on the monitored current output from the voltage conversion unit, the main control unit controls the main drive device to shift the phase of the AC current of the main motor windings, so as to minimize the current output from the power conversion unit, thereby minimizing the apparent power of the wind system.

[0015] As described above, the air system includes a junction box, the main motor unit is directly electrically connected to the junction box, and the slave motor unit is electrically connected to the main motor unit.

[0016] In the wind system described above, the junction box and the slave motor unit are located on opposite sides of the main motor unit.

[0017] The air system described above can be a modular unit, a fan module group, a fan coil unit, a fresh air system, an air-cooled water system, and an air handling unit. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of one embodiment of the wind system of this application.

[0019] Figure 2 This is a functional block diagram of one embodiment of the motor assembly in the wind system of this application.

[0020] Figure 3 yes Figure 2 The diagram shows an embodiment of the drive mechanism in the main motor unit and the slave motor unit.

[0021] Figure 4 yes Figure 2 The block diagram of the main control unit is shown in the figure.

[0022] Figure 5 This is a flowchart of one embodiment of a control method for a motor assembly. Detailed Implementation

[0023] Various specific embodiments of this application will now be described with reference to the accompanying drawings, which form part of this specification. It should be understood that, where possible, the same or similar reference numerals used in this application refer to the same parts.

[0024] The air system described in this application may be a modular unit, a fan module group, a fan coil unit, a fresh air system, an air-cooled water system, and an air handling unit, etc.

[0025] Figure 1 This is a structural schematic diagram of one embodiment of the wind system 100. Figure 1In the illustrated embodiment, the air system 100 includes a housing 101, a main motor unit 10 and a slave motor unit 20 arranged within the housing 101, a coil 102, and a junction box 104. The housing 101 includes a mounting plate 111, and the junction box 104 is fixed to one end of the mounting plate 111, providing a wiring port for the user. The wiring port includes a power interface and a control signal interface. The main motor unit 10 is connected to the junction box 104 via a wire 112 to connect to power and receive control commands. The slave motor unit 20 is connected to the main motor unit 10 via a wire 113 to connect to power and receive control signals from the main motor unit 10. The main motor unit 10 and the slave motor unit 20 are physically separated. The main motor unit 10 is located between the junction box 104 and the slave motor unit 20. This arrangement and connection of the main motor unit 10, the slave motor unit 20, and the junction box 104 reduces the length of the wires connecting them, thereby facilitating manufacturing and saving costs. The coil 102 is fixed to the housing 101 of the air system 100, facing the mounting plate 111, and is used to hold cold or hot water for heat exchange with indoor air.

[0026] like Figure 1 As shown, the main motor unit 10 is connected to fans 105 and 106 on both sides via shaft 109, and the slave motor unit 20 is connected to fans 107 and 108 on both sides via shaft 110. The housings of the main motor unit 10 and the slave motor unit 20 are equipped with brackets (not shown), and the main motor unit 10 and the slave motor unit 20 are fixedly connected to the mounting plate 111 of the air system 100 via the brackets. The volutes of fans 105, 106, 107, and 108 are fixed to the mounting plate 111.

[0027] like Figure 1 As shown, an air outlet duct 103 is provided in the housing 101. The main motor unit 10 and the slave motor unit 20 drive the fans 105, 106, 107, and 108 to rotate, creating a negative pressure at the air inlet of the air system 100, thereby allowing indoor air to enter the air system 100. The main motor unit 10 and the slave motor unit 20 drive the fans 105, 106, 107, and 108 to rotate, so that the air entering the air system 100, after exchanging heat with the water in the coil 102, enters the single air outlet duct 103 and is released into the room through the outlet of the single air outlet duct 103 (e.g., ...). Figure 1 (As indicated by the arrow). In Figure 1 In the illustrated embodiment, the coil 102 is disposed in the outlet air duct 103. In other embodiments, the coil 102 may also be disposed in the inlet air duct (not shown).

[0028] Despite Figure 1In one embodiment, the wind system employs one master motor unit and one slave motor unit. In other embodiments, the wind system may employ one master motor unit and two or more slave motor units. In a wind system employing two or more slave motor units, each slave motor unit is connected to the master motor unit via a corresponding wire to receive power and control signals from the master motor unit. Although in Figure 1 In one embodiment, each motor unit of the wind system drives two fans; in other embodiments, each motor unit of the wind system may drive only one fan.

[0029] In one embodiment, the main motor unit 10 may be an electronically commutated motor, and the slave motor unit 20 may be a brushless DC motor.

[0030] Figure 2 yes Figure 1 The functional block diagram of one embodiment of the motor assembly shown includes a main motor unit 10 and a slave motor unit 20.

[0031] like Figure 2 As shown, the main motor unit 10 includes a power conversion unit 201, a main drive device 202, a main motor 203, a main control unit 204, and a main motor I / O interface 206. In another embodiment, the main motor I / O interface 206 may also be a wireless control module.

[0032] The power conversion unit 201 of the main motor unit 10 is configured to receive AC power (e.g., a single-phase voltage of 220V / 50Hz or a three-phase voltage of 380V / 50Hz) and convert the received AC power into DC power (e.g., DC310V or DC540V) to supply to the main drive unit 202. The main drive unit 202 performs bidirectional PWM conversion on the DC power output by the power conversion unit 201 to form a bidirectional PWM voltage (i.e., inverter voltage) with controllable effective value and frequency, which is then supplied to the windings of the main motor 203. Specifically, the main drive unit 202 is equipped with a device (e.g., a commutator or inverter) to generate inverter voltage. After the inverter voltage is applied to the windings of the main motor 203, it forms an alternating current to drive the main motor 203 to rotate. Because the main drive unit 202 is located in the main motor unit 10, the wire length from the main drive unit 202 to the main motor 203 is short, which can effectively reduce electromagnetic interference generated by the inverter voltage output from the main drive unit 202 to the main motor 203. The main control unit 204 receives control commands from the external control center and starts the air system based on the control commands. The control commands received by the main control unit 204 from the external control center can be 0-10V voltage signals, 220V ON / OFF signals, pulse sequences, Modbus commands, etc. The main control unit 204 generates control signals based on the control commands received from the external control center to control the frequency and effective value of the inverter voltage output from the main drive unit 202 to the main motor 203, thereby controlling the rotation of the main motor 203. The rotation of the main motor simultaneously induces a voltage in the windings. Figure 2 In this embodiment, the control signal generated by the main control unit 204 is a PWM control signal. The main control unit 204 detects the operating parameters of the main motor 203, including speed, inverter voltage, winding AC current, winding induced voltage, etc., and changes the frequency or duty cycle of the PWM control signal based on the operating parameters to control the rotation of the main motor 203. The main control unit 204 may include LED indicators to indicate system status and fault information. In some embodiments, the main control unit 204 may generate a PWM feedback signal to indicate the operating parameters of the main motor 203 and output the PWM feedback signal to an external control center. Although the control signal used by the main control unit 204 to control the main drive device 202 and the signal fed back by the main control unit 204 to the external control center in this embodiment are PWM signals, other forms of control and feedback signals may be used in other embodiments.

[0033] According to the settings of the main control unit 204, the main motor 203 can operate in several different working modes. In this embodiment, the working modes of the main motor 203 include constant speed mode, constant torque mode, or constant power mode. The main control unit 204 controls the effective value and frequency of the inverter voltage output by the main drive device 202, thereby controlling the effective value and frequency of the AC current in the windings of the main motor 203. Based on this frequency, the main motor 203 determines to operate in one of the constant speed mode, constant torque mode, or constant power mode to achieve the required rotational target parameters (speed, torque, power).

[0034] When the main motor 203 is rotating in constant speed mode, if the main control unit 204 detects that the speed of the main motor 203 is less than the target speed, the main control unit 204 increases the frequency of the PWM control signal output to the main drive device 202, thereby increasing the frequency of the inverter voltage output from the main drive device 202 to the main motor 203. This increases the frequency of the AC current in the windings of the main motor 203, thus increasing the speed of the main motor 203. Conversely, if the main control unit 204 detects that the speed of the main motor 203 is greater than the target speed, the main control unit 204 decreases the frequency of the PWM control signal sent to the main drive device 202, thereby decreasing the frequency of the inverter voltage output from the main drive device 202 to the main motor 203. This decreases the frequency of the AC current in the windings of the main motor 203, thus decreasing the speed of the main motor 203.

[0035] When the main motor 203 is rotating in constant torque mode, if the main control unit 204 detects that the current of the main motor 203 is less than the effective value of the winding AC current corresponding to the target torque, the main control unit 204 increases the frequency of the PWM control signal output to the main drive device 202. This increases the frequency of the inverter voltage output from the main drive device 202 to the main motor 203, thereby increasing the frequency of the winding AC current of the main motor 203 and thus increasing the speed of the main motor 203. According to the fan law, the air volume output by the fan system is directly proportional to the motor speed. As the speed of the main motor 203 increases, the air volume output by the fan system increases. With the increase in the air volume output by the fan system, the load on the fan system increases, thus increasing the power demand on the motor. Furthermore, according to the fan law, the power of the motor is directly proportional to the cube of the motor speed. Therefore, this will cause the required torque of the fan system to increase in order to meet the increased motor power demand. Therefore, the main control unit 204 increases the duty cycle of the PWM control signal output to the main drive unit 202, thereby increasing the effective value of the inverter voltage output by the main drive unit 202. This increases the effective value of the winding AC current of the main motor 203, thus increasing the torque of the main motor 203. Conversely, if the main control unit 204 detects that the current of the main motor 203 is greater than the effective value of the winding AC current corresponding to the target torque, the main control unit 204 decreases the frequency of the PWM control signal output to the main drive unit 202. This reduces the frequency of the inverter voltage output by the main drive unit 202 to the main motor 203, thereby reducing the frequency of the winding AC current of the main motor 203 and decreasing the speed of the main motor 203. Because the speed of the main motor 203 decreases, the required torque of the wind system decreases. At this time, the main control unit 204 reduces the duty cycle of the PWM control signal output to the main drive device 202, thereby reducing the effective value of the inverter voltage output by the main drive device 202, which in turn reduces the effective value of the winding AC current of the main motor 203, thereby reducing the torque of the main motor 203.

[0036] When the main motor 203 is rotating in constant power mode, the main control unit 204 detects the product of the inverter voltage and AC current of the main motor 203, i.e., the power of the main motor 203. If the power of the main motor 203 is less than the target power, the main control unit 204 increases the frequency and duty cycle of the PWM control signal output to the main drive device 202, causing the frequency and effective value of the inverter voltage output by the main drive device 202 to increase synchronously, thereby causing the frequency and effective value of the AC current in the windings of the main motor 203 to increase synchronously, thus increasing the power of the main motor 203. Conversely, if the power of the main motor 203 detected by the main control unit 204 is greater than the target power, the main control unit 204 decreases the frequency and duty cycle of the PWM control signal output to the main drive device 202, causing the frequency and effective value of the inverter voltage output by the main drive device 202 to decrease synchronously, thereby causing the frequency and effective value of the AC current in the windings of the main motor 203 to decrease synchronously, thus decreasing the power of the main motor 203.

[0037] In constant speed mode, the main control unit 204 only needs to change the frequency of the PWM control signal output to the main drive device 202 according to the control command sent by the external control center to adjust the speed of the main motor 203, which is easy to implement in the design.

[0038] Compared to constant speed mode, constant torque and constant power modes ensure less airflow reduction. This is because constant torque and constant power modes minimize airflow reduction when issues such as filter or vent blockage occur in the air system. Specifically, in constant torque mode, when issues such as filter or vent blockage occur, the static pressure of the air system increases, the load decreases, and the airflow decreases, thus reducing the demand on motor torque. The main control unit 204 detects a decrease in the effective value of the AC current in the windings of the main motor 203, indicating a decrease in the torque of the main motor 203. It then promptly increases the frequency of the AC current in the windings of the main motor 203 by increasing the frequency of the inverter voltage output from the main drive unit 202, thereby increasing the speed of the main motor 203 and increasing the torque required by the air system. Subsequently, by increasing the effective value of the inverter voltage output from the main drive unit 202, the effective value of the AC current in the windings of the main motor 203 is increased, thereby increasing the torque of the main motor 203 to reach the target value, thus ensuring stable airflow. Similarly, in constant power mode, when issues such as filter or vent blockage occur in the air system, the static pressure of the air system increases, the load decreases, and the airflow decreases, thus reducing the air system's demand on motor power. The main control unit 204 can detect the decrease in the power of the main motor 203 by detecting the inverter voltage output from the main drive unit 202 and the AC current in the windings of the main motor 203. It can then promptly increase the effective value and frequency of the inverter voltage output from the main drive unit 202, thereby increasing the effective value and frequency of the AC current in the windings of the main motor 203, thus increasing the power of the main motor 203 to the target value, thereby reducing the airflow attenuation.

[0039] like Figure 2 As shown, the slave motor unit 20 includes a slave motor I / O interface 207, a slave drive device 208, a feedback unit 209, and a slave motor 210. The master motor unit 10 and the slave motor unit 20 communicate with each other by connecting the master motor I / O interface 206 and the slave motor I / O interface 207. In another embodiment, the slave motor I / O interface 207 can also be a wireless control module.

[0040] The drive unit 208 receives DC power from the power conversion unit 201 and a Vsp command signal from the main control unit 204 via the main motor I / O interface 206 and the slave motor I / O interface 207, respectively. This Vsp command signal can be a varying voltage from 0-5V. The drive unit 208 controls the rotational speed of the slave motor 210 based on the voltage change of the Vsp command signal received from the main control unit 204. The higher the voltage value of the Vsp signal, the greater the rotational speed of the slave motor 210 controlled by the Vsp signal. Since the drive unit 208 is located within the slave motor unit 20, the wire length from the drive unit 208 to the slave motor 210 is short, effectively reducing electromagnetic interference generated by the inverter voltage output from the drive unit 208 to the slave motor 210. The feedback unit 209 of the slave motor unit 20 detects the rotational speed of the slave motor 210 and generates a PWM feedback signal based on the rotational speed of the slave motor 210, which is then output to the main control unit 204 of the main motor unit 10. The main control unit 204 controls the speed of the slave motor 210 based on the feedback signal. Although the signal fed back from the feedback unit 209 to the main control unit 204 in this embodiment is a PWM signal, other forms of feedback signals can be used in other embodiments. In some embodiments, the main control unit 204 can feed the feedback signal back to an external control center. Since both the feedback signal indicating the operating parameters of the main motor 203 and the feedback signal indicating the operating parameters of the slave motor 210 are fed back to the external control center through the main control unit 204, the wiring ports in the junction box are simpler, which simplifies the structure of the junction box and reduces the complexity and difficulty of wiring for users.

[0041] The main control unit 204 can control the slave motor 210 to rotate in a speed-following mode via the Vsp signal from the drive unit 208. When the slave motor 210 rotates in speed-following mode, the Vsp signal from the main control unit 204 controls the drive unit 208 to drive the slave motor 210 to rotate at a specific speed. This specific speed can be equal to, less than, or greater than the speed of the main motor 203 by a predetermined value. The heat exchange capacity requirements for the coil areas corresponding to the main motor unit 10 and the slave motor unit 20 may be the same or different. By controlling the slave motor 210 to rotate at the same or different speed as the main motor 203, the heat exchange capacity of different coil areas can be controlled separately to meet the different heat exchange capacity requirements of different coil areas.

[0042] The main control unit 204 can set the actual target speeds of the main motor 203 and the slave motor 210 to avoid resonance in the wind system 100. Assuming the motor speed causing resonance in the wind system 100 is Nr, the wind system 100 can avoid resonance when the difference between the speeds of the main motor 204 and the slave motor 210 and the resonance speed Nr respectively reaches at least a predetermined damping amount Δ. According to an embodiment of this application, the main control unit 204 parses the command signal received from an external control center to determine the ideal target speed Nm of the main motor 204 and the ideal target speed Ns of the slave motor 210 corresponding to the command signal, and determines whether the difference between the ideal target speeds Nm and Ns of the main motor 204 and the resonance speed Nr respectively reaches or exceeds the predetermined damping amount Δ. If the difference between the ideal target speeds Nm and Ns of the main motor 203 and the resonance speed Nr respectively reaches or exceeds the predetermined damping amount Δ, that is, if... [(Nr≥Nm+Δ) or (Nr≤Nm-Δ)], and [(Nr≥Ns+Δ) or (Nr≤Ns-Δ)], The main control unit 204 sets the ideal target speed Nm as the actual target speed of the main motor 203, and sets the ideal target speed Ns as the actual target speed of the slave motor 210. If the difference between the ideal target speed and the resonant speed Nr of at least one of the main motor 204 and the slave motor 210 does not reach the predetermined vibration damping amount Δ, that is, (Nr < Nm + Δ) or (Nr > Nm - Δ) or (Nr > Ns + Δ) or (Nr < Ns - Δ), the main control unit 204 adjusts the actual target speeds of the main motor 204 and the slave motor 210. In one embodiment, if the difference between the ideal target speed and the resonant speed Nr of at least one of the main motor 204 and the slave motor 210 does not reach a predetermined damping amount Δ, when the ideal target speed Nm of the main motor 203 is greater than or equal to the ideal target speed Ns of the slave motor 210 (i.e., Nm ≥ Ns), the main control unit 204 sets the actual target speed of the main motor 203 to Nm + nΔ, and sets the actual target speed of the slave motor 210 to Ns - nΔ; conversely, when the ideal target speed Nm of the main motor 203 is less than the ideal target speed Ns of the slave motor 210 (i.e., Nm < Ns), the main control unit 204 sets the actual target speed of the main motor 203 to Nm - nΔ, and sets the actual target speed of the slave motor 210 to Ns + nΔ. Thus, this application enables the wind system to avoid resonance. Furthermore, when the ideal target speed of the main motor 203 and / or the slave motor 210 does not meet the vibration damping requirements, since the embodiments of this application set the actual target speed of one of the main motor 203 and the slave motor 210 to be greater than its ideal target speed, and set the actual target speed of the other to be less than its ideal target speed, and make the absolute value of the difference between the actual target speed and their respective ideal target speeds the same (i.e., nΔ), the wind system of this application can achieve the desired performance of the system while avoiding resonance. n can be set to a positive integer of 2 or greater as needed. The setting of the predetermined vibration damping amount Δ is related to the motor control accuracy and the resonance speed Nr. The predetermined vibration damping amount Δ can be set to ≥5 rpm to adapt to the engineering capabilities of the current general wind system motor control accuracy. If the engineering capabilities of the wind system motor control accuracy are improved, Δ can be set to a smaller value. When the resonance speed Nr = 600~1200 rpm, the predetermined vibration damping amount Δ can be set to 6 rpm. If the resonance speed Nr is higher, the predetermined vibration damping amount Δ can be set to a larger value.

[0043] like Figure 1As shown, the air system of this application has only one outlet duct 103. Because there is only one outlet duct 103, the method of controlling the operation of the slave motor unit 20 through the main control unit 204 is particularly advantageous. For an air system with only one outlet duct 103, if the main motor unit 10 and the slave motor unit 20 are controlled by different control devices, the two motors cannot be monitored and controlled synchronously due to the independence of these devices. The mutual interference of the airflow (wind) generated by the fans driven by the two motors entering the common outlet duct 103 adversely affects the control of the two motors' operation. For example, if the two motors are controlled by different independent control devices, when both the first and second motors are running in constant torque mode, after the control device of the first motor receives a control command from the external control center indicating an increase in Vsp, the control device of the first motor recognizes this command as a torque increase. The control device of the first motor then increases the speed of the first motor to achieve the torque increase required by the air system, and the static pressure in the outlet duct 103 increases accordingly. As the static pressure increases, the load decreases, the airflow decreases, and thus the torque demand on the motor decreases. Therefore, the control device of the second motor detects a decrease in the AC current of the second motor windings. At this time, due to the superimposed constant torque regulation characteristic of the second motor and the control command from the external control center to increase torque, the second motor is prone to overshoot during torque adjustment. After overshoot, the control device of the second motor will initiate an adjustment to reduce the speed of the second motor based on the constant torque regulation characteristic to reduce the torque of the second motor. Furthermore, during this process of the first motor increasing torque and the second motor decreasing torque, there is a pressure difference in the airflow generated by the fans of the first and second motors in the air outlet duct 103. However, the Vsp command requires the same target torque for both the first and second motors, so it will reverse and enter the process of the first motor decreasing torque and the second motor increasing torque. Similarly, this situation occurs when the first and second motors are running in constant power mode. When the first motor receives a control command from the external control center instructing Vsp to increase, the control device of the first motor recognizes the command as a power increase. The control device of the first motor therefore increases the speed and torque of the first motor to achieve the required power increase, and the static pressure in the air outlet duct 103 increases accordingly. As static pressure increases, load decreases, and airflow diminishes, thus reducing the power demand on the motor. Consequently, the control device for the second motor detects a decrease in the AC current of the second motor's windings. At this point, due to the constant power regulation characteristics superimposed on the second motor and the external control center's control command to increase power, overshoot is likely to occur during power adjustment of the second motor. After overshoot, the control device for the second motor will, based on the constant power regulation characteristics, initiate adjustments to reduce the speed and torque of the second motor to decrease its power.Furthermore, during the process of the first motor increasing power and the second motor decreasing power, a pressure difference exists in the airflow generated by the fans of the first and second motors in the air outlet duct 103. However, the Vsp command requires the same target power for both the first and second motors, thus reversing the process to reduce the power of the first motor and increase the power of the second motor. In summary, if the two motors are controlled by independent control devices, the motor operating in constant torque or constant power mode will never reach its target torque or power. In this application, the rotation of both the main motor 203 and the slave motor 210 is controlled by the main control unit 204, and the monitoring and control of the main motor 203 and the slave motor 210 can be synchronized. Therefore, the main control unit 204 will not be affected by the speed change of the slave motor 210, which is beneficial for accurately controlling the rotation of the main motor 203 and the slave motor 210, so that the main motor 203 can reach its target torque or power when operating in constant torque or constant power mode.

[0044] Since both the main motor 203 and the slave motor 210 receive DC high-voltage power from the power conversion unit 201 of the main motor unit 10 to drive them, the main control unit 204 can monitor the voltage and current output from the power conversion unit 201 and control the main drive device 202 to shift the phase of the AC current of the main motor 203 based on the monitored current, thereby minimizing the apparent power of the wind system. Specifically, when the AC currents of the main motor 203 and the slave motor 210 are in phase, their phases are superimposed, resulting in the maximum current output from the power conversion unit 201, at which point the apparent power of the wind system is maximized. To minimize the apparent power of the wind system, the main control unit 204 monitors the current output from the power conversion unit 201. Based on the monitored current output from the power conversion unit 201, the main control unit 204 controls the main drive device 202 to shift the phase of the AC current of the main motor 203. This causes the current of the main motor 203 to cancel out the AC current of the slave motor 210, thereby minimizing the current output from the power conversion unit 201. When the current output from the power conversion unit 201 is minimized, the power output from the power conversion unit 201 is minimized. That is, the apparent power of the wind system is minimized, and therefore the power factor of the wind system is maximized.

[0045] Figure 3 yes Figure 2A more detailed schematic diagram of the main drive unit 202 and the slave drive unit 208 is shown below. The main drive unit 202 and the slave drive unit 208 may include a commutator 301. The commutator 301 may be an electronic commutator. The commutator 301 can convert the DC power supply from the power conversion unit 201 into a current with a changing flow direction in the windings of the main motor 203 to drive the main motor 203. The commutator 301 can change the frequency of the AC current in the motor windings according to the control signal (i.e., the PWM control signal) from the main control unit 204.

[0046] Figure 4 yes Figure 2 The diagram shows a schematic block representation of the main control unit 204. Figure 4 As shown, the main control unit 204 includes a bus 401. A processor 402, a memory 403, a mass storage device 404, an input interface 405, and an output interface 406 are connected to the bus 401. In other embodiments, the input and output interfaces may also be wireless control modules. The processor 402 can read programs (or instructions) from the memory 403 or the mass storage device 404 and execute the programs (or instructions) to perform control functions on the master motor 203 and the slave motor 210; the processor 402 can also write data or instructions into the memory 403 or the mass storage device 404. The memory 403 and the mass storage device 404 can store programs (instructions) or data. Typically, the memory 403 has a faster access speed than the mass storage device 404, while the mass storage device 404 has a larger memory size than the memory 403. By executing instructions in the memory 403, the processor can control the memory 403, the mass storage device 404, the input interface 405, and the output interface 406.

[0047] Input interface 405 receives input from an external control center and converts the input into signals recognizable by processor 402. Input interface 405 also obtains operating parameters of the main motor 203 from the detection device of the main motor unit 10 and converts them into signals recognizable by processor 402. Input interface 405 also receives feedback signals from feedback unit 209 indicating the rotational speed of slave motor 210. Output interface receives control signals from processor 402 and converts the control signals into outputs suitable for the main drive unit 202 and slave drive unit 208.

[0048] During operation, upon receiving control commands from an external control center, the processor 402 executes the required functions based on the input from the external control center. When the operating parameters of the main motor 203 are obtained from the detection device of the main motor unit 10, the processor 402 controls the rotation of the main motor 203 via the main drive unit 202 according to the operating parameters. When a feedback signal indicating the rotational speed of the slave motor 210 is received from the feedback unit 209, the processor 402 controls the rotation of the slave motor 210 via the slave drive unit 208 according to the feedback signal. Similarly, during operation, when the processor 402 receives a control signal, the output interface 406 outputs the control signal to the main drive unit 202 and the slave drive unit 208 to control the rotation of the main motor 203 and the slave motor 210. When needed, the output interface 406 outputs signals indicating the operating parameters of the main motor 203 and the slave motor 210 to the external control center.

[0049] Figure 5 This is a flowchart of the control method for the motor components of a wind system.

[0050] In step 501, the control flow begins.

[0051] In step 502, power is supplied to the wind system, and the wind system is initialized.

[0052] In step 503, the main control unit 204 of the main motor unit 10 monitors control commands from an external control center. These control commands can be 0-10V variable voltage signals, 220V ON / OFF signals, pulse sequences, Modbus commands, etc.

[0053] In step 504, the main control unit 204 of the main motor unit 10 determines whether the control command from the external control center instructs the start of the air system. If the control command does not instruct the start of the air system, the process returns to step 503, and the main control unit 204 continues to monitor the control commands from the external control center. If the control command instructs the start of the air system, step 505 is executed.

[0054] In step 505, the main control unit 204 sends a control signal to the main drive device 202, and the main control unit 204 drives the main motor 203 through the main drive device 202 to start the main motor 203.

[0055] In step 506, the main control unit 204 determines whether the main motor 203 has started. The main control unit 204 determines whether the main motor 203 has started by monitoring whether its speed has reached its minimum speed. If the main control unit 204 detects that the main motor 203 has not reached its minimum speed, it returns to step 505, where the main control unit 204 drives the main motor 203 through the main drive device 202 to start the main motor 203. If the main control unit 204 detects that the main motor 203 has reached its minimum speed, the main control unit 204 determines that the main motor 203 has successfully started and proceeds to step 507.

[0056] In step 507, the main control unit 204 sends a control signal to the main drive unit 202 to control the frequency and effective value of the inverter voltage output by the main drive unit 202, thereby controlling the frequency and effective value of the AC current in the winding of the main motor 203, so that the main motor 203 rotates according to a predetermined operating mode. According to the settings of the main control unit 204, the main motor 203 rotates in one of three modes: constant speed, constant torque, or constant power. By controlling the frequency of the inverter voltage output by the main drive unit 202, the main control unit 204 can also ensure that the main motor 203 avoids the resonance speed that causes resonance in the wind system.

[0057] In step 508, the master control unit 204 sends a Vsp signal to the slave motor I / O interface through the master motor I / O interface. In embodiments of a wind system including multiple slave motor units, the master control unit 204 sends the Vsp signal to the selected slave motor unit as needed.

[0058] In step 509, the drive unit 208 controls the slave motor 210 to rotate in a predetermined following mode based on the Vsp signal from the main control unit 204. Depending on the voltage value of the Vsp signal, the slave motor 210 rotates at the same speed as the main motor 203, or at a higher or lower speed than the main motor 203. The Vsp signal can also cause the slave motor 210 to avoid resonance speeds that cause resonance in the air system.

[0059] In step 510, the main control unit 204 determines the operating status of the main motor 203 and 210 based on the detected operating parameters of the main motor 203 and the received feedback signal indicating the operating parameters of the slave motor 210 (this feedback signal is provided by the feedback unit 209). If the main control unit 204 determines that the operating parameters of the main motor 203 (e.g., speed, torque, power) and the operating parameters of the slave motor 210 (e.g., speed) meet the target requirements, it returns to step 503, and the main control unit 204 continues to monitor control commands from the external control center. If the main control unit 204 determines that the operating parameters of the main motor 203 (e.g., speed, torque, power) and the operating parameters of the slave motor 210 (e.g., speed) do not meet the target requirements, it executes step 511.

[0060] In step 511, if the main control unit 204 determines that the operating parameters (e.g., speed, torque, power) of the main motor 203 do not meet the target requirements, the main control unit 204 will take corresponding actions, such as stopping the air system or indicating a fault through the LED lights of the main control unit 204. If the main control unit 204 determines that the operating parameters (e.g., speed) of the main motor 203 do not meet the target value, the main control unit 204 will take corresponding actions, such as stopping the slave motor 210, stopping the air system, or indicating a fault through the LED lights of the main control unit 204.

[0061] In step 512, the control flow ends.

[0062] like Figure 5 The program of the flowchart shown can be stored in Figure 4 The main control unit 204 shown is stored in the memory 403 or mass storage device 404 and can be executed by the processor 402.

[0063] The embodiments of this application include at least the following beneficial technical effects: 1. Since both the main motor and the slave motor are controlled by the main control unit of the main motor, the monitoring and control of the main motor and the slave motor can be synchronized, thereby avoiding the inaccuracy of the control of the main motor caused by the mutual interference of the airflow generated by the fan drive of the main motor and the slave motor in a single air outlet duct. Therefore, the main motor can achieve its target torque or power when running in constant torque or constant power mode.

[0064] 2. The motor assembly can operate in one of three modes: constant speed, constant torque, or constant power. Therefore, the air system of this application offers flexible operating modes, providing both a simple design mode and a mode with minimal airflow attenuation, thus meeting diverse application requirements.

[0065] 3. The arrangement and connection of the main motor unit, slave motor unit, and junction box save on wire length and reduce costs.

[0066] 4. Since the feedback signals indicating the working parameters of the main motor and the slave motor in this application are fed back to the external control center through the main control unit, the wiring ports in the junction box are simpler, which can simplify the structure of the junction box and reduce the complexity and difficulty of wiring for users.

[0067] 5. Since the main drive unit is located in the main motor unit and the slave drive unit is located in the slave motor unit, the wire lengths from the main drive unit to the main motor and from the slave drive unit to the slave motor are short, which can effectively reduce electromagnetic interference.

[0068] 6. By appropriately setting the actual target speeds of the main motor and the slave motor, this application can avoid vibration in the air system while simultaneously achieving the desired performance of the air system.

[0069] It should be understood that the present application, disclosed and defined herein, extends to all alternative combinations of two or more individual features mentioned or obvious in the text and / or drawings. All these different combinations constitute various alternative aspects of the invention. The embodiments described herein illustrate one way of implementing the present application and will enable others skilled in the art to implement the invention. The claims should be construed as including alternative embodiments that are permitted by prior art.

Claims

1. A wind system, the wind system comprising: The main motor unit (10) and the slave motor unit (20). The main motor unit includes: Main control unit (204); A main drive unit (202), configured to receive a first control signal from the main control unit (204) and thereby be controlled by the main control unit (204); and A main motor (203) configured to be driven by the main drive unit (202); The slave motor unit (20) includes: The slave drive device (208) is configured to receive a second control signal from the master control unit (204) and thereby be controlled by the master control unit (204); and Slave motor (210), the slave motor being configured to be driven by the slave drive device (208); The main motor unit (10) operates in constant speed mode, constant torque mode, or constant power mode. The operating parameters of the main motor (203) include the rotational speed of the main motor (203), the winding AC current of the main motor (203), and the inverter voltage of the main motor (203). The main control unit (204) is configured as follows: The main control unit (204) can control the speed of the main motor (203) through the main drive device (202) according to the speed of the main motor (203). The main control unit (204) can control the torque of the main motor (203) through the main drive device (202) according to the AC current of the winding of the main motor (203). The main control unit (204) can control the power of the main motor (203) through the main drive device (202) based on the product of the winding AC current and the inverter voltage of the main motor (203).

2. In the wind system according to claim 1, the main motor unit (10) and the slave motor unit (20) are physically separate motor units.

3. The wind system according to claim 1, wherein the main motor unit (10) and the slave motor unit (20) are configured to communicate with each other via the main motor I / O interface (206) and the slave motor I / O interface (207).

4. The wind system according to claim 1, wherein the main control unit (204) is configured to receive the working status signal of the slave motor (210) and control the operation of the slave motor (210) according to the working status signal of the slave motor (210).

5. The wind system according to claim 1, wherein the main control unit (204) is configured to issue the second control signal to control the rotational speed of the slave motor (210) via the slave drive device (208).

6. The wind system according to claim 5, wherein the main control unit (204) can be configured to control the slave motor unit (20) to operate in a speed following mode, wherein when operating in the speed following mode, the main control unit (204) sends the second control signal to control the slave motor (210) to rotate at a specific speed through the slave drive device (208), wherein the specific speed includes the same speed as the main motor (203), or a speed less than or greater than the main motor (203).

7. The wind system according to claim 6, wherein the main control unit (204) is configured as follows: Receive and parse command signals received from an external control center to determine the ideal target speed of the main motor and the ideal target speed of the slave motor corresponding to the command signals, and determine whether the difference between the ideal target speed of the main motor and the ideal target speed of the slave motor and the resonance speed that causes the wind system to resonate reaches the predetermined vibration damping amount respectively. If the difference between the ideal target speed of the main motor and the ideal target speed of the slave motor and the resonant speed both reach or exceed the predetermined damping amount, the main control unit (204) sets the ideal target speed of the main motor to the actual target speed of the main motor and sets the ideal target speed of the slave motor to the actual target speed of the slave motor. and If the difference between at least one of the ideal target speed of the main motor and the ideal target speed of the slave motor and the resonant speed does not reach the predetermined vibration damping amount, When the ideal target speed of the main motor is greater than or equal to the ideal target speed of the slave motor, the main control unit (204) sets the first adjustment target speed of the main motor to the actual target speed of the main motor, and sets the first adjustment target speed of the slave motor to the actual target speed of the slave motor. and When the ideal target speed of the main motor is less than the ideal target speed of the slave motor, the main control unit (204) sets the second adjustment target speed of the main motor to the actual target speed of the main motor, and sets the second adjustment target speed of the slave motor to the actual target speed of the slave motor. in, The first target adjustment speed of the main motor = the ideal target speed of the main motor + n × predetermined vibration damping amount; the first target adjustment speed of the slave motor = the ideal target speed of the slave motor - n × predetermined vibration damping amount; and The second adjustment target speed of the main motor = the ideal target speed of the main motor - n × predetermined vibration damping amount; the second adjustment target speed of the slave motor = the ideal target speed of the slave motor + n × predetermined vibration damping amount. Where n is selected from 2 or a positive integer greater than 2.

8. The wind system according to claim 1, wherein the main motor unit (10) includes a power conversion unit (201), and the main control unit (204) is configured to monitor the current output from the power conversion unit (201) and, based on the monitored current, control the main drive device (202) to shift the phase of the winding AC current of the main motor (203) so that the current output from the power conversion unit (201) is minimized, thereby minimizing the apparent power of the wind system.

9. The air system according to claim 1, wherein the air system includes a junction box (104), the main motor unit (10) is electrically connected to the junction box (104), and the slave motor unit (20) is electrically connected to the main motor unit (10).

10. The air system according to claim 9, wherein the junction box (104) and the slave motor unit (20) are located on both sides of the main motor unit (10).

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