TWI555324B - DC brushless motor control system for AC power supply - Google Patents

Description

DC brushless motor control system for AC power

The invention relates to a control system, in particular to a method for converting an input alternating current signal into a direct current signal, thereby controlling a DC brushless motor drive to achieve energy saving and power saving, and without replacing the old pipeline wiring, Control interface control system

Nowadays, due to high energy prices and serious heat pollution, green environmental protection issues continue to promote energy conservation and alternative energy sources. However, alternative energy development is not easy. Therefore, the first priority is to save energy. For example, air conditioning systems in general buildings usually consume electricity. The high amount is quite wasteful of energy. The main reason is that the air-conditioning system has multiple ventilation ducts and multiple blowers in each floor space to achieve the effect of adjusting room temperature and circulating air. These blower motors are all AC single-phase three-speed. The motor is a kind of motor with low efficiency and high power consumption. It is quite wasteful in energy use. At present, a DC brushless motor is introduced on the market with high efficiency and low power consumption. Therefore, if the blower can be switched to a DC brushless motor, It can improve the high power consumption of the air conditioning system, thereby achieving the goal of energy saving and environmental protection.

The following is a description of the common air conditioning system blower control circuit structure. The conventional air conditioning system has a blower motor that is an AC single-phase three-speed motor that uses an alternating current (AC) power supply to control its high, medium, and low speeds through an alternating current (AC) controller. And a control interface such as a temperature sensor, a twist switch, etc., to provide different speed signals to the AC controller to control the speed of the AC single-phase three-speed motor.

The traditional air conditioning system has its blower motor powered by an alternating current (AC) power source. AC single-phase three-speed motor, and set the complex relay control circuit to be turned on and off in the circuit structure. It is also possible to control the speed of the AC single-phase three-speed motor by the action of different relays. The conventional air conditioning system has the blower motor as the exchange single. The phase three-speed motor is powered by an alternating current (AC) power supply, and a plurality of single-axis double-switching relays (Relay-SPDT, Relay-single pole double throw) control circuit are turned on and off in the circuit structure to switch the power supply, high speed, medium speed. Or a low-speed single-axis dual-switch relay (Relay-SPDT, Relay-single pole double throw) to control the AC single-phase three-speed motor.

It can be seen from the above that since the conventional air conditioning system uses an alternating current signal, or other electrical equipment such as an air filtration system or a dehumidification system uses an alternating current signal, and the direct current brushless motor cannot read the alternating current signal, it must be constructed. All the pipeline wirings are disassembled and replaced for use in DC brushless motors. The cost of replacement is not only a waste, but the entire wiring replacement work is a complicated project. It will cost a lot of control circuitry and will not allow the user to choose the control interface that is already used; therefore, how to change the old air conditioning system to high power and low consumption with minimum cost and minimum engineering construction. The DC brushless motor of electric power has always been a problem that the industry needs to break through.

In view of the above, the present invention mainly provides a control system for converting an input AC signal into a DC signal, thereby controlling the DC brushless motor drive to achieve energy saving purposes, and the present invention does not need to replace the old pipeline wiring. Or control interface for its main purpose.

In order to achieve the above, the control system of the present invention is electrically connected between a main control module and a brushless motor. The control system includes at least: a switching power conversion circuit, a voltage conversion circuit, and a central processing circuit. , motor drive circuit and switching circuit, by the intersection The switching power conversion circuit is connected to the air conditioning main control module and receives an AC power supply, and the AC power is rectified and step-down filtered to form a stable DC power supply for the DC brushless motor to operate, so that the conventional air conditioning system is not required By replacing the old pipeline wiring and the control interface, the alternating current signal in the air conditioning system is converted into a direct current signal by the invention, thereby controlling the DC brushless motor drive to achieve the purpose of energy saving.

According to the above main structural features, the switching power conversion circuit has mutually connected rectifying elements, current limiting elements, voltage stabilizing elements, and filtering elements.

The above-mentioned rectifying element is provided with a plurality of diodes connected in series.

According to the above main structural features, the current limiting component is connected between the rectifying component and the stabilizing component, and the current limiting component is provided with at least one resistor.

According to the above main structural features, the voltage stabilizing element is connected between the current limiting element and the filter element, and the voltage stabilizing element is provided with a diode and a Zener diode connected in series.

According to the above main structural features, the filter component is provided with at least one resistor and a capacitor connected to each other.

According to the above main structural features, the control system is further provided with a Hall element, which is respectively connected to the voltage conversion circuit and the central processing circuit.

The above switching circuit is a transistor.

According to the above main structural features, the control system can be applied to an air conditioning system, an air filtration system or a dehumidification system.

Specifically, the control system disclosed in the present invention can produce the following effects:

1. The control system is connected to the air conditioning main control module and receives an AC power supply, and the AC power is rectified and step-down filtered to form a stable DC power supply for the DC brushless motor to operate, which not only improves efficiency but also achieves The purpose of energy saving.

2. The invention can make the traditional air conditioning system directly change the induction motor to a DC brushless motor without replacing the old pipeline wiring or control interface.

3. Under the operation of the Shangke Hall element, the rotational speed and rotational position of the inner rotor of the brushless DC motor can be controlled.

10‧‧‧Control system

11‧‧‧Switching power conversion circuit

111‧‧‧Rectifying components

112‧‧‧ Current limiting components

113‧‧‧Regulator components

114‧‧‧Filter components

115‧‧‧ diode

116‧‧‧resistance

117‧‧‧Jenner diode

118‧‧‧ Capacitance

12‧‧‧Voltage conversion circuit

13‧‧‧Central Processing Circuit

14‧‧‧Motor drive circuit

15‧‧‧Switching circuit

16‧‧‧ Hall element

20‧‧‧Main control module

30‧‧‧DC brushless motor

31‧‧‧Fan

41‧‧‧ indoor end

42‧‧‧Outdoor

43‧‧‧Compressor

The first figure is a basic architecture diagram of the control system of the first embodiment of the present invention.

The second figure is a circuit diagram of the control system of the first embodiment of the present invention.

The third figure is a circuit diagram of the switching power conversion circuit of the present invention.

The fourth figure is a circuit diagram of the control system of the second embodiment of the present invention.

The fifth figure is a schematic diagram of the use of the control system in the air conditioning system of the present invention.

As shown in the first figure, the control system 10 of the present invention is substantially electrically connected between a main control module 20 and a brushless motor 30. The control system 10 includes at least one switching power supply. a conversion circuit 11, a voltage conversion circuit 12, a central processing circuit 13, a motor drive circuit 14, and a switching circuit 15; wherein: the switching power conversion circuit 11 is connected to the air conditioning main control module 20 and receives an AC power supply, The AC power source is converted into a DC power source. Please refer to FIG. 2 and FIG. 3 simultaneously. The switching power supply conversion circuit 11 has a rectifying element 111, a current limiting element 112, a voltage stabilizing element 113, and a filtering element 114 connected to each other.

The rectifying element 111 is provided with a plurality of diodes 115 connected in series in the forward direction. The current limiting element 112 is connected between the rectifying element 111 and the stabilizing element 113. The current limiting element 112 is provided with at least a resistor 116, the voltage stabilizing element 113 is connected to the current limiting component 112 The voltage stabilizing element 113 is provided with a diode 115 and a Zener diode 117 connected in series with each other. The filter element 114 is provided with at least one resistor 116 and a capacitor 118 connected to each other.

The voltage conversion circuit 12 is connected to the switching power conversion circuit 11 to convert the DC power supply into at least one driving voltage.

The central processing circuit 13 is respectively connected to the switching power conversion circuit 11 and the voltage conversion circuit 12, and can receive the driving voltage and the signal of the switching power conversion circuit 11; the motor driving circuit 14 is respectively converted with the voltage The circuit 12 and the central processing circuit 13 are connected to receive the above-mentioned driving voltage, and receive the signal of the central processing circuit 13 to be converted into a driving signal of the driving motor.

The switching circuit 15 is connected to the motor driving circuit 14, the voltage converting circuit 12, and the DC brushless motor 30, and can receive the driving voltage, receive the driving signal, and drive the DC brushless motor 30 to operate. In the embodiment of the invention, the switching circuit 15 is a transistor.

In use, the air conditioning main control module 20 provides an AC power supply to the switching power conversion circuit 11, firstly rectifying the AC power by a rectifying element 111 formed by a plurality of diodes 115 connected in series, and then by the resistor 116. The current limiting function is performed, and the voltage is stabilized by the diode 115 and the sigma diode 117, and the voltage waveform is corrected by using the resistor 116 and the capacitor 118 as a filter component to form a stable DC power source, and the AC power source is completed. Conversion.

The voltage conversion circuit 12 receives the stable DC power supply and converts it into at least one driving voltage. The voltage conversion circuit 12 can be a buck converter to convert the DC power of the large voltage into a plurality of different driving voltages, for example, The conversion is made to a lower voltage to supply the central processing circuit 13, the motor drive circuit 14, and the switching circuit 15, and can be converted into a driving voltage that can drive the operation of the brushless DC motor 30.

And the signal of the switching power conversion circuit 11 is transmitted to the central processing power The circuit 13 is processed by the central processing circuit 13 and converted into a driving signal for driving the motor via the motor driving circuit 14. Finally, the driving signal is controlled to operate the DC brushless motor 30 via the switching circuit 15.

The central processing circuit can also have the following control modes:

1. You can choose to drive in sine wave or square wave mode.

2. It can detect the different input AC power of the front end as the basis for judging the speed of the DC brushless motor. For example, according to the size of different input AC power, the DC brushless motor can be controlled to form different speeds of 2, 3, 4 and so on.

3. The voltage modulation of the input motor can be performed by PWM (Pulse Width Modulation).

Furthermore, the control system is further provided with a Hall element 16, as shown in the second embodiment of the fourth figure, the Hall element 16 is respectively connected to the voltage conversion circuit 12 and the central processing circuit 13, and the Hall element can be 16 detects the magnetic pole change of the permanent magnet of the inner rotor of the brushless DC motor to form a weak Hall voltage, and transmits it to the central processing circuit 13 to control the rotational speed and rotational position of the inner rotor of the brushless DC motor.

It is worth mentioning that the control system of the present invention can be integrated on a circuit board and can be directly installed between the air conditioning main control module and the DC brushless motor, so that the traditional air conditioning system does not need to be replaced. Some pipeline wiring or control interface directly converts the induction motor into a DC brushless motor, and uses the operation of the DC brushless motor to achieve the purpose of improving efficiency and saving energy.

In addition, the present invention can also be used in the embodiment shown in FIG. 5 , the control system 10 is applied to an air conditioning system 40 having a main control module 20 and a DC brushless motor 30 . The control system 10 is electrically connected between the main control module 20 and the DC brushless motor 30. Alternatively, in the embodiment shown in the figure, the control system 10 is built in the DC brushless The motor 30 is electrically connected to the main control module 20, wherein the air conditioning system 40 has an indoor end 41 and an outdoor end 42, wherein the DC brushless motor 30 is disposed in the Between the indoor end 41 and the outdoor end 42, the DC brushless motor 30 is respectively provided with a fan 31 corresponding to the indoor end 41 and the outdoor end 42, and the control system 10 is connected to the DC brushless motor 30, The DC brushless motor 30 is driven to operate, and the DC brushless motor 30 is used to drive the fans 31 at both ends thereof to rotate, and at the same time, the fans 31 respectively pass the airflow to the indoor end 41 or the outdoor via the action of a compressor 43. The end 42 is guided to achieve the effect of a predetermined temperature adjustment.

Of course, the control system of the present invention can be further applied to an air filtration system or a dehumidification system, wherein the air filtration system or the dehumidification system has a suction end and a discharge end, and the DC brushless motor is connected A fan, and the fan is located between the suction end and the discharge end, and can be cleaned or dehumidified by the treatment of internal components.

In summary, the present invention provides a preferred and feasible control system, and an application for an invention patent is provided according to the law; the technical content and technical features of the present invention have been disclosed above, but those skilled in the art may still be based on the present invention. It is to be understood that various changes and modifications may be made without departing from the spirit of the invention. Therefore, the scope of the present invention should be construed as being limited by the scope of the appended claims

10‧‧‧Control system

11‧‧‧Switching power conversion circuit

12‧‧‧Voltage conversion circuit

13‧‧‧Central Processing Circuit

14‧‧‧Motor drive circuit

15‧‧‧Switching circuit

20‧‧‧Air conditioning main control module

30‧‧‧DC brushless motor

Claims (12)

A DC brushless motor control system for AC power is basically electrically connected between a main control module and a DC brushless motor. The control system includes at least one switching power conversion circuit for receiving An AC power source converts the AC power source into a DC power source, wherein the switching power source conversion circuit has mutually connected rectifying elements, current limiting elements, voltage stabilizing elements, and filter elements; wherein the current limiting element is connected to the rectifying Between the component and the voltage stabilizing component, the current limiting component is provided with at least one resistor; the voltage stabilizing component is connected between the current limiting component and the filter component, and the voltage regulator component is provided with two poles connected in series And the filter element is provided with at least one resistor and a capacitor connected to each other; a voltage conversion circuit is connected to the switching power conversion circuit to convert the DC power source into at least one driving voltage; a central processing circuit is respectively connected to the switching power conversion circuit and the voltage conversion circuit to receive the driving voltage, and the central portion The circuit can detect different input AC power sources of the front end as a basis for judging the speed of the DC brushless motor. The system controls the DC brushless motor to form a plurality of different speeds and speeds according to different input AC power sources; a motor drive circuit is Connected to the voltage conversion circuit and the central processing circuit, respectively, receiving the driving voltage, and receiving the signal of the central processing circuit to be converted into a driving signal; and a switching circuit respectively connected to the motor driving circuit and the voltage conversion circuit , receiving the above driving signal. A DC brushless motor control system as claimed in claim 1, wherein the rectifying element is provided with a plurality of diodes connected in series. A DC brushless motor control system as claimed in claim 1 or 2, wherein the control system is further provided with a Hall element, the Hall element being respectively connected to the voltage conversion circuit and the central processing circuit. A DC brushless motor control system as claimed in claim 1 or 2, wherein the switching circuit is a transistor. A DC brushless motor control system as claimed in claim 1 or 2, wherein the central processing circuit is selectable in a sine wave or square wave drive mode. The DC brushless motor control system for an AC power source according to claim 1 or 2, wherein the central processing circuit performs voltage modulation of the input motor in a PWM (Pulse Width Modulation) manner. The DC brushless motor control system for an AC power source according to claim 1 or 2, wherein the control system is applied to an air conditioning system having a main control module and a DC brushless motor. The control system is electrically connected between the main control module and the DC brushless motor, and the switching circuit is connected to the DC brushless motor to drive the DC brushless motor to operate. The DC brushless motor control system of the present invention, wherein the air conditioning system has an outdoor end and an indoor end, and the two ends of the DC brushless motor are respectively connected with a fan, and the two fans respectively Corresponding to the outdoor end and the indoor end. A DC brushless motor control system for an AC power source according to claim 1 or 2, wherein the control system is applied to an air filtration system having a main control module and a brushless brushless a motor, wherein the control system is electrically connected between the main control module and the DC brushless motor, and the switching circuit is connected to the DC brushless motor to drive the DC brushless motor to operate. The DC brushless motor control system of claim 9, wherein the air filter system has a suction end and a discharge end, and the DC brushless motor is connected to a fan, and the fan is located Between the suction end and the discharge end. The DC brushless motor control system of claim 1 or 2, wherein the control system is applied to a dehumidification system, the air conditioning system has a main control module and a brushless motor. The control system is electrically connected between the main control module and the DC brushless motor, and the switching circuit is connected to the DC brushless motor to drive the DC brushless motor to operate. The DC brushless motor control system as claimed in claim 11, wherein the dehumidification system has a suction end and a discharge end, and the DC brushless motor is connected to a fan, and the fan is located in the suction. Between the end and the discharge end.