TWI811792B - Motor controller - Google Patents

Abstract

A motor controller comprises a switch circuit and a control unit. The switch circuit is coupled to a motor for driving the motor. The control unit is configured to generate a plurality of control signals to control the switch circuit. The motor controller utilizes a duty cycle conversion mechanism, such that the motor controller is operated in a constant voltage driving mode or a constant current driving mode. The motor controller is configured to avoid generating switching noise by the constant voltage driving mode or the constant driving current mode. The motor controller is configured to increase a success rate of starting the motor.

Description

Motor controller

The present invention relates to a motor controller, and in particular to a motor controller applicable to a fan motor system.

Traditionally, the driving methods of motors can be divided into two types. One is to use a Hall sensor to switch phases to drive the motor. The other is to drive the motor without a Hall sensor. Since Hall sensors are easily affected by the external environment, resulting in reduced sensing accuracy, and installing Hall sensors will increase the size and cost of the system, sensorless driving methods have been proposed to solve the above problems. problem.

In the sensorless driving method, the motor controller can switch phases by detecting the back electromotive force of a floating phase or a phase current. Generally speaking, a motor controller will output a pulse width modulation signal to control the speed of the motor. However, when the motor controller is in a pulse width modulation driving mode, switching noise will be generated at the output end of the motor controller. This switching noise may cause misjudgment of detected voltage or current, causing the motor to operate abnormally. Therefore, a new technology is needed to overcome the deficiencies of previous technologies.

In view of the above problems, an object of the present invention is to provide a motor controller applicable to a fan motor system. The motor controller has a switching circuit, a control unit, and a pulse width modulation processing unit. The switch circuit has a first transistor, a second transistor, a third transistor, a fourth transistor, a first terminal, and a second terminal. The switching circuit is coupled to a motor to drive the motor. The control unit is used to generate a plurality of control signals to control the switch circuit. The pulse width modulation processing unit generates a first pulse width modulation signal to the control unit according to a second pulse width modulation signal, wherein the first pulse width modulation signal has a first duty cycle and the second The pulse width modulation signal has a second duty cycle. The pulse width modulation processing unit may use a duty cycle curve graph or a duty cycle lookup table to generate the first pulse width modulation signal. As the second duty cycle increases, the first duty cycle increases accordingly.

The motor controller can use a certain voltage driving mode or a certain current driving mode to drive the motor. Specifically, the motor controller can utilize a duty cycle conversion mechanism so that the motor controller operates in the constant voltage driving mode or the constant current driving mode, and the control unit can be used to execute the duty cycle conversion mechanism. When the motor controller is in the constant voltage driving mode and the first duty cycle of the first pulse width modulation signal is larger, the certain voltage output by the motor controller is larger. The constant voltage may be equal to a voltage difference between the first endpoint and the second endpoint. In addition, the constant voltage may be in a proportional relationship with the first working period. For example, the constant voltage may be equal to the first duty cycle multiplied by an input voltage. At this time, the motor controller can maintain the original output energy and eliminate switching noise at the same time. When the input voltage changes, the motor controller can maintain an output energy constant through a modulation mechanism. Similarly, when the motor controller is in the constant current driving mode and the first duty cycle is larger, the motor controller outputs a larger current. The constant current may be equal to a current flowing between the first endpoint and the second endpoint. The constant current may be in a proportional relationship with the first working period. The motor controller uses the constant voltage driving mode or the constant current driving mode to improve the success rate of starting the motor.

According to an embodiment of the present invention, the motor controller can utilize a duty cycle switching mechanism so that the motor controller operates in a non-pulse width modulation driving mode. The motor controller can utilize the non-PWM driving mode to drive the motor in a starting state, a slow starting state, or a normal operating state. motor. The motor controller can utilize a pulse width modulation drive mode to drive the motor during a normal operating state. In addition, the motor controller improves the success rate of starting the motor through the non-pulse width modulation driving mode. Through the non-pulse width modulation driving mode, the motor controller can avoid generating a switching noise, thus overcoming the shortcomings of the prior art.

10: Motor controller

M: Motor

100: Switch circuit

101:The first transistor

102: Second transistor

103:Third transistor

104: The fourth transistor

O1: first endpoint

O2: Second endpoint

VCC: third endpoint

GND: fourth endpoint

110:Control unit

C1: first control signal

C2: Second control signal

C3: The third control signal

C4: The fourth control signal

120: Pulse width modulation processing unit

Vp1: first pulse width modulation signal

Vp2: second pulse width modulation signal

Figure 1 is a schematic diagram of a motor controller according to an embodiment of the present invention.

The following description will make the objects, features, and advantages of the present invention more apparent. Preferred embodiments according to the present invention will be described in detail with reference to the drawings.

Figure 1 is a schematic diagram of a motor controller 10 according to an embodiment of the present invention. The motor controller 10 has a switching circuit 100, a control unit 110, and a pulse width modulation processing unit 120. The switch circuit 100 has a first transistor 101, a second transistor 102, a third transistor 103, a fourth transistor 104, a first terminal O1, and a second terminal O2 for driving One motor M. The motor M is coupled to the first endpoint O1 and the second endpoint O2. The first transistor 101 is coupled to the first terminal O1 and a third terminal VCC and the second transistor 102 is coupled to the first terminal O1 and a fourth terminal GND. The third transistor 103 is coupled to the second terminal O2 and the third terminal VCC and the fourth transistor 104 is coupled to the second terminal O2 and the fourth terminal GND. The third terminal VCC has an input voltage, where the input voltage may be a power supply voltage. The first transistor 101, the second transistor 102, the third transistor 103, and the fourth transistor 104 may be a P-type metal oxide semi-transistor or an N-type metal oxide semi-transistor. As shown in FIG. 1 , the first transistor 101 and the third transistor 103 are two P-type metal oxide semi-transistors as an example. The second transistor 102 and the fourth transistor 104 are two N-type metal oxide semi-transistors as an example. The control unit 110 generates a first control signal C1, a second control signal C2, and a third control signal C3, and a fourth control signal C4 are used to respectively control the conduction conditions of the first transistor 101, the second transistor 102, the third transistor 103, and the fourth transistor 104. The control unit 110 receives a first pulse width modulation signal Vp1 to control the switching circuit 100, wherein the first pulse width modulation signal Vp1 has a first duty cycle. The first PWM signal Vp1 may be an output PWM signal. The pulse width modulation processing unit 120 generates a first pulse width modulation signal Vp1 to the control unit 110 according to a second pulse width modulation signal Vp2, where the second pulse width modulation signal Vp2 has a second duty cycle. The second PWM signal Vp2 may be an input PWM signal. The PWM processing unit 120 may use a duty cycle curve graph or a duty cycle lookup table to generate the first PWM signal Vp1. As the second duty cycle increases, the first duty cycle increases accordingly. In addition, the motor controller 10 can be applied to a fan motor system to enable a fan to operate normally.

The control unit 110 can alternately provide electric energy to the motor M from a first driving mode and a second driving mode. In the first driving mode, the control unit 110 turns on the first transistor 101 and the fourth transistor 104 by controlling the first control signal C1 and the fourth control signal C4. At this time, the current flows from the third terminal VCC through the first transistor 101, the motor M, the fourth transistor 104, and the fourth terminal GND in sequence, transmitting electric energy to the motor M in this mode. In the second driving mode, the control unit 110 turns on the second transistor 102 and the third transistor 103 by controlling the second control signal C2 and the third control signal C3. At this time, the current flows from the third terminal VCC through the third transistor 103, the motor M, the second transistor 102, and the fourth terminal GND in sequence, thereby transmitting electric energy to the motor M in this mode. By repeatedly switching between the first driving mode and the second driving mode, the motor M can be made to operate normally.

The motor controller 10 may adopt a certain voltage driving mode or a certain current driving mode to drive the motor M. Through the constant voltage driving mode or the constant current driving mode, the motor controller 10 can avoid generating switching noise, thereby overcoming the shortcomings of the prior art. Specifically, the motor controller 10 may utilize a duty cycle conversion mechanism so that the motor controller 10 operates in a constant voltage driving mode or a constant current driving mode, and the control unit 110 may be used to execute the duty cycle conversion mechanism. When the motor controller 10 is in constant voltage driving mode and the larger the first duty cycle of the first pulse width modulation signal Vp1 is, the greater the certain voltage output by the motor controller 10 is. The constant voltage may be equal to the voltage difference between the first terminal O1 and the second terminal O2. In addition, the constant voltage can be proportional to the first duty cycle. For example, the constant voltage may be equal to the first duty cycle multiplied by the input voltage. That is to say, when the first duty cycle is 50%, the constant voltage is 1/2 the input voltage. At this time, the motor controller 10 can maintain the original output energy and eliminate switching noise at the same time. When the input voltage changes, the motor controller 10 can maintain the output energy constant through a modulation mechanism. Similarly, when the motor controller 10 is in the constant current driving mode and the first duty cycle is larger, the motor controller 10 outputs a larger current. The constant current may be equal to the current flowing between the first terminal O1 and the second terminal O2. The constant current can be proportional to the first working cycle. Designers can choose to use a constant voltage drive mode or a constant current drive mode to drive the motor M according to different applications. According to an embodiment of the present invention, the motor controller 10 can use a non-pulse width modulation driving mode to control the switching circuit 100 to output a specific energy, thereby allowing the motor M to operate normally while eliminating switching noise. Through the non-pulse width modulation driving mode, the motor controller 10 can be used to improve the success rate of starting the motor M. Furthermore, the motor controller 10 can be applied to a single-phase motor or a multi-phase motor. The motor controller 10 can switch phases by detecting the back electromotive force or a phase current of a floating phase.

Since the back electromotive force may be too small during the starting process, the motor controller 10 may use a constant voltage drive mode or a constant current drive mode to drive the motor M in a starting state to avoid misjudgment of a commutation point. That is to say, the motor controller 10 can use the non-PWM driving mode to drive the motor M in the starting state. When the motor controller 10 is in a normal operating state and the first working period is too small, the motor controller 10 may use a constant voltage drive mode or a constant current drive mode to drive the motor M to avoid misjudgment of a commutation point. Therefore, when the motor controller 10 is in a normal operating state, the designer can use a constant voltage drive mode, a constant current drive mode, or a pulse width modulation drive mode to drive the motor M according to different operating conditions or applications. In addition, the motor controller 10 can drive the motor M using a constant voltage drive mode or a constant current drive mode in a slow start state. That is to say, the motor controller 10 can be in the slow start state The motor M is driven using a non-pulse width modulation driving mode.

According to an embodiment of the present invention, the motor controller 10 can be applied to a sensorless motor system, a DC motor system, and a brushless motor system. The motor controller 10 utilizes a duty cycle conversion mechanism to operate in a certain voltage driving mode or a certain current driving mode to improve the success rate of starting the motor M. The motor controller 10 drives the motor M through a non-pulse width modulation driving mode to overcome the shortcomings of the prior art. The motor controller 10 can operate in a non-PWM driving mode according to a duty cycle switching mechanism.

Although the present invention has been illustrated by preferred embodiments, it should be understood that the present invention is not limited to the disclosed embodiments. On the contrary, the invention is intended to cover various modifications and similar arrangements obvious to those skilled in the art. Accordingly, the patentable scope should be given the broadest interpretation so as to include all such modifications and similar configurations.

The above are only preferred embodiments of the present invention, and all equivalent changes and modifications made in accordance with the patentable scope of the present invention shall fall within the scope of the present invention.

10: Motor controller

M: Motor

100: Switch circuit

101:The first transistor

102: Second transistor

103:Third transistor

104: The fourth transistor

O1: first endpoint

O2: Second endpoint

VCC: third endpoint

GND: fourth endpoint

110:Control unit

C1: first control signal

C2: Second control signal

C3: The third control signal

C4: The fourth control signal

120: Pulse width modulation processing unit

Vp1: first pulse width modulation signal

Vp2: second pulse width modulation signal

Claims (48)

A motor controller includes: a switching circuit coupled to a motor for driving the motor; and a control unit for generating a plurality of control signals to control the switching circuit, wherein the motor controller utilizes a duty cycle to switch The mechanism enables the motor controller to operate in a certain voltage driving mode or a certain current driving mode. A motor controller as described in item 1 of the patent application, wherein the motor controller is applied to a sensorless motor system. The motor controller as described in Item 1 of the patent application, wherein the motor controller uses the constant voltage drive mode or the constant current drive mode to avoid generating a switching noise. For the motor controller described in item 1 of the patent application, the control unit is used to execute the duty cycle conversion mechanism. The motor controller as described in item 1 of the patent application, wherein the motor controller uses the constant voltage drive mode or the constant current drive mode to improve the success rate of starting the motor. The motor controller as described in item 1 of the patent application, wherein the switch circuit has a first endpoint and a second endpoint. When the motor controller is in the constant voltage driving mode, the motor controller outputs A certain voltage is equal to a voltage difference between the first endpoint and the second endpoint. The motor controller described in item 1 of the patent application, wherein the switch circuit has a A first endpoint and a second endpoint. When the motor controller is in the constant current driving mode, a certain current output by the motor controller is equal to the current flowing between the first endpoint and the second endpoint. a current. As in the motor controller described in item 1 of the patent application, the control unit receives a first pulse width modulation signal to control the switching circuit, and the first pulse width modulation signal has a first duty cycle. The motor controller as described in item 8 of the patent application, wherein when the motor controller is in the constant voltage driving mode and the first working cycle is larger, the motor controller outputs a certain voltage that is larger. For example, in the motor controller described in Item 9 of the patent application, the constant voltage has a proportional relationship with the first working cycle. For the motor controller described in item 9 of the patent application, the constant voltage is equal to the first working period multiplied by an input voltage. For the motor controller described in item 11 of the patent application, the input voltage is a power supply voltage. The motor controller described in Item 8 of the patent application, wherein when the motor controller is in the constant current driving mode and the first working cycle is larger, the motor controller outputs a larger certain current. For example, in the motor controller described in Item 13 of the patent application, the constant current has a proportional relationship with the first working cycle. For example, the motor controller described in item 1 of the patent application, wherein when an input voltage changes, the motor controller maintains an output energy constant through a modulation mechanism. The motor controller described in item 1 of the patent application, wherein the motor controller is applied to a single-phase motor or a multi-phase motor. The motor controller as described in item 1 of the patent application, wherein the motor controller uses the constant voltage driving mode to drive the motor in a starting state. The motor controller as described in item 1 of the patent application, wherein the motor controller uses the constant current drive mode to drive the motor in a starting state. The motor controller as described in item 1 of the patent application, wherein the motor controller uses the constant voltage drive mode to drive the motor in a slow start state. The motor controller as described in item 1 of the patent application, wherein the motor controller uses the constant current drive mode to drive the motor in a slow start state. The motor controller as described in item 1 of the patent application, wherein the motor controller uses the constant voltage drive mode to drive the motor in a normal operating state. The motor controller as described in item 1 of the patent application, wherein the motor controller uses the constant current drive mode to drive the motor in a normal operating state. The motor controller as described in item 1 of the patent application, wherein the motor controller uses a pulse width modulation driving mode to drive the motor in a normal operating state. The motor controller as described in item 1 of the patent application, wherein the switch circuit includes: a first transistor coupled to a first terminal and a third terminal; a second transistor coupled to the third terminal. a terminal and a fourth terminal; a third transistor coupled to a second terminal and the third terminal; and a fourth transistor coupled to the second terminal and the fourth terminal . The motor controller as described in item 1 of the patent application, wherein the motor controller further includes a pulse width modulation processing unit, and the pulse width modulation processing unit generates a first pulse width modulation signal according to a second pulse width modulation signal. The pulse width modulation signal is sent to the control unit, the first pulse width modulation signal has a first duty cycle, and the second pulse width modulation signal has a second duty cycle. As in the motor controller described in claim 25, the pulse width modulation processing unit generates the first pulse width modulation signal using a duty cycle curve. In the motor controller described in claim 25 of the patent application, the pulse width modulation processing unit uses a duty cycle lookup table to generate the first pulse width modulation signal. As for the motor controller described in item 25 of the patent application scope, when the second working week As the period increases, the first working period increases. The motor controller as described in item 1 of the patent application, wherein the motor controller is applied to a fan motor system. A motor controller as described in item 1 of the patent application, wherein the motor controller is applied to a DC motor system. A motor controller as described in item 1 of the patent application, wherein the motor controller is applied to a brushless motor system. The motor controller as described in item 1 of the patent application, wherein the motor controller switches phases by detecting the back electromotive force of a floating phase. The motor controller as described in item 1 of the patent application, wherein the motor controller switches phases by detecting a phase current. A motor controller includes: a switching circuit coupled to a motor for driving the motor; and a control unit for generating a plurality of control signals to control the switching circuit, wherein the motor controller utilizes a duty cycle to switch The mechanism enables the motor controller to operate in a certain voltage driving mode. The motor controller as described in item 34 of the patent application, wherein the motor controller is Applied to a sensorless motor system. The motor controller as described in item 34 of the patent application, wherein the motor controller uses the constant voltage drive mode to start the motor in a starting state. The motor controller as described in item 34 of the patent application, wherein the motor controller uses the constant voltage drive mode to drive the motor in a slow start state. The motor controller as described in item 34 of the patent application, wherein the motor controller uses the constant voltage drive mode to drive the motor in a normal operating state. A motor controller includes: a switching circuit coupled to a motor for driving the motor; and a control unit for generating a plurality of control signals to control the switching circuit, wherein the motor controller utilizes a duty cycle to switch The mechanism enables the motor controller to operate in a certain current driving mode. The motor controller as described in Item 39 of the patent application, wherein the motor controller is applied to a sensorless motor system. The motor controller as described in item 39 of the patent application, wherein the motor controller uses the constant current drive mode to start the motor in a starting state. The motor controller as described in item 39 of the patent application, wherein the motor controller is The constant current drive mode is used to drive the motor in a slow start state. The motor controller as described in item 39 of the patent application, wherein the motor controller uses the constant current drive mode to drive the motor in a normal operating state. A motor controller includes: a switching circuit coupled to a motor for driving the motor; and a control unit for generating a plurality of control signals to control the switching circuit, wherein the motor controller utilizes a duty cycle to switch mechanism so that the motor controller operates in a non-pulse width modulation drive mode. The motor controller as described in item 44 of the patent application, wherein the motor controller is applied to a sensorless motor system. The motor controller as described in Item 44 of the patent application, wherein the motor controller uses the non-pulse width modulation driving mode to start the motor in a starting state. The motor controller as described in item 44 of the patent application, wherein the motor controller uses the non-pulse width modulation driving mode to drive the motor in a slow start state. The motor controller as described in item 44 of the patent application, wherein the motor controller uses the non-pulse width modulation driving mode to drive the motor in a normal operating state.

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