Brushless direct current motor controller

Abstract

The invention discloses a brushless direct current motor controller. The device comprises a control module, a power supply module, a driving module, a current acquisition module and a communication module. The power supply module is electrically connected with the control module and is used for supplying power to the control module; the control module is connected with the motor through the driving module and is used for driving the motor to work; an input end of the current acquisition module is connected with the motor, an output end of the current acquisition module is connected with the control module, and the current acquisition module is used for acquiring a current signal of the motor and sending the current signal to the control module, so that the control module calculates an electrical angle of the motor according to the current signal and controls phase change of the motor according to the electrical angle; and enabling the control module to judge whether overcurrent occurs or not according to the current value, and further controlling the driving module to perform corresponding action. The control module is connected with an upper computer through the communication module. The device does not need a position sensor, has the advantages of low cost, small size and the like, reduces the space occupation of equipment, and improves the space utilization rate.

Description

Technical Field

[0001] The present invention relates to the technical field of motor controllers, and in particular to a brushless direct current motor controller. Background Art

[0002] Brushless DC motors (BLDC) have been widely used in various fields due to their advantages such as fast, controllable, high efficiency and high reliability. Conventional brushless DC motor controllers rely on position sensors such as Hall sensors to obtain the position of the motor shaft to achieve current commutation. The advantage is that the controller is easy to control commutation, but the disadvantage is that it increases the complexity, cost and volume of the motor, limiting the application of the motor. Therefore, brushless DC motors without position sensors with small size, low cost and relatively simple manufacturing process and their controller design have become a hot topic in current research.

[0003] With regard to the brushless DC motor controller in the prior art, which relies on position sensors such as Hall sensors to obtain the position of the motor shaft to achieve current commutation, resulting in large size and high cost, no effective solution has been proposed so far. Summary of the invention

[0004] A brushless DC motor controller is provided in an embodiment of the present invention to solve the problems of large size and high cost caused by the brushless DC motor controller in the prior art, which relies on position sensors such as Hall sensors to obtain the position of the motor shaft to achieve current commutation.

[0005] To achieve the above-mentioned purpose, the present invention provides a brushless DC motor controller, which includes: a control module, a power module, a drive module, a current acquisition module and a communication module; the power module is electrically connected to the control module for supplying power to the control module; the control module is connected to the motor through the drive module for driving the motor to work; the input end of the current acquisition module is connected to the motor, and the output end is connected to the control module, for collecting the current signal of the motor and sending it to the control module, so that the control module can calculate the electrical angle of the motor according to the current signal and control the motor commutation according to the electrical angle, and the control module can judge whether there is overcurrent according to the current value, and then control the drive module to perform corresponding actions; the control module is connected to the host computer through the communication module.

[0006] Optionally, it also includes: a bus voltage detection module; the input end of the bus voltage detection module is connected to the motor, and the output end is connected to the control module, and is used to collect the bus voltage of the motor and send it to the control module, so that the control module can judge whether it is overvoltage or undervoltage according to the voltage value, and then control the drive module to perform corresponding actions.

[0007] Optionally, it also includes: a temperature detection module; the input end of the temperature detection module is connected to the motor, and the output end is connected to the control module, for collecting the temperature of the motor and sending it to the control module, so that the control module determines whether it is overheated according to the temperature value, and then controls the drive module to perform corresponding actions.

[0008] Optionally, the control module includes: an overvoltage / undervoltage detection AD port, a temperature detection AD port, a current detection AD port and a PWM generator port; the overvoltage / undervoltage detection AD port is connected to the bus voltage detection module; the temperature detection AD port is connected to the temperature detection module; the current detection AD port is connected to the current acquisition module; and the PWM generator port is connected to the drive module.

[0009] Optionally, the control module is an ARM chip.

[0010] Optionally, the power supply module includes: a power supply, a DC48V / 12V conversion submodule, a DC12V / 5V conversion submodule, and a DC12V / 3.3V conversion submodule.

[0011] Optionally, the driving module includes: a dual-input gate driving chip and an NMOSFET tube; the dual-input gate driving chip is connected to the motor through the NMOSFET tube.

[0012] Optionally, the current acquisition module includes: a current sensing amplifier N1.

[0013] Optionally, the temperature detection module is a temperature sensor RT1.

[0014] Optionally, the communication module is a 232 communication level conversion chip, which is used to realize the conversion between the TTL level and RS232 level of the control module and the host computer.

[0015] Beneficial effects of the present invention:

[0016] The present invention provides a brushless DC motor controller, which comprises: a power module, a control module, a drive module, a communication module, a current acquisition module, a bus voltage detection module and a temperature detection module; the control module first drives the motor to rotate through the drive module, collects the current signal of the motor through the current acquisition module and sends it to the control module, so that the control module calculates the electrical angle of the motor according to the current signal and controls the motor commutation according to the electrical angle; it does not require a position sensor, has the advantages of low cost and small size, reduces the space occupation of the equipment, and improves the space utilization rate; and during the rotation of the motor, the phase current is detected for current limiting protection, the temperature is detected for over-temperature protection, and the bus voltage is detected for over-voltage or under-voltage protection, which can increase the service life of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a system composition block diagram of a brushless DC motor controller provided by an embodiment of the present invention;

[0018] Figure 2 is a circuit diagram of a power module provided by an embodiment of the present invention;

[0019] Figure 3 is a circuit diagram of a driving module provided by an embodiment of the present invention;

[0020] Figure 4 is a circuit diagram of a current acquisition module provided in an embodiment of the present invention;

[0021] Figure 5 is a circuit diagram of a communication module provided by an embodiment of the present invention;

[0022] Figure 6 is a circuit diagram of a bus voltage detection module provided by an embodiment of the present invention;

[0023] Figure 7 4 is a circuit diagram of a temperature detection module provided in an embodiment of the present invention.

[0024] Explanation of symbols:

[0025] Control module-1, power module-2, drive module-3, current acquisition module-4, communication module-5, bus voltage detection module-6, temperature detection module-7, host computer-8, motor-9. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Conventional brushless DC motor 9 controllers rely on position sensors such as Hall sensors to obtain the position of the motor 9 shaft to achieve current commutation. The advantage is that the controller is convenient for commutation control. The disadvantage is that it increases the complexity, cost, and volume of the motor 9, limiting the application occasions of the motor 9. Therefore, a brushless DC motor 9 with a smaller size, lower cost, and relatively simple manufacturing process and a controller design scheme without a position sensor have become a hot topic in current research.

[0028] Therefore, the present invention provides a low-cost, small-volume, position sensor-free brushless DC motor 9 controller design solution. Figure 1: is a system block diagram of a brushless DC motor 9 controller provided by an embodiment of the present invention. Figure 1 As shown, the brushless DC motor 9 controller includes:

[0029] Control module 1, power module 2, drive module 3, current acquisition module 4 and communication module 5;

[0030] The power module 2 is electrically connected to the control module 1 and is used to supply power to the control module 1;

[0031] Due to product space limitations, the control module 1 of the present invention uses a smaller ARM chip.

[0032] Figure 2 is a circuit diagram of a power module 2 provided in an embodiment of the present invention, such as Figure 2 As shown, the power supply module 2 includes: a power supply, a DC48V / 12V conversion submodule, a DC12V / 5V conversion submodule, and a DC12V / 3.3V conversion submodule.

[0033] The power supply is 48V, and the power supply 48V obtains 12V voltage through the DC48V / 12V conversion submodule, and the 12V voltage supplies power to the drive module 3; the 12V voltage obtains 5V voltage through the DC12V / 5V conversion submodule, and the 5V voltage supplies power to the communication module 5; the 12V voltage obtains 3.3V voltage through the DC12V / 3.3V conversion submodule, and the 3.3V voltage is used for the control module 1, and the 3.3V voltage is isolated by magnetic beads to obtain +3.3Va power supply for the current acquisition module 4, the bus voltage detection module 6, and the temperature detection module 7. Each submodule in the power module 2 uses a non-isolated power supply. When designing the PCB of the power module 2, the board is divided into regions, and then each region is single-point grounded through a 0-ohm resistor to achieve circuit isolation, which can effectively prevent electromagnetic interference.

[0034] The control module 1 is connected to the motor 9 through the driving module 3, and is used to drive the motor 9 to work;

[0035] Specifically, the control module 1 includes: a PWM generator port, and the PWM generator port is connected to the motor 9 through the driving module 3 to drive the motor 9 to work.

[0036] Figure 3 is a circuit diagram of the driving module 3 provided in an embodiment of the present invention, such as Figure 3 As shown, the driving module 3 includes: a dual-input gate driving chip and an NMOSFET tube;

[0037] The dual-input gate drive chip is connected to the motor 9 via an NMOSFET tube.

[0038] Specifically, the present invention adopts three dual-input gate drive chips U1 with output interlock dead zone, whose withstand voltage is 600V, supply voltage is 12V, and compatible with 3.3V, 5V and 15V level input logic. The control module 1 controls the three U1 dual-input gate drive chips to switch Q1 and Q2 of the three groups of NMOSFET tubes and drive the motor 9 to change phase.

[0039] The input end of the current acquisition module 4 is connected to the motor 9, and the output end is connected to the control module 1, and is used to collect the current signal of the motor 9 and send it to the control module 1, so that the control module 1 can calculate the electrical angle of the motor 9 according to the current signal and control the commutation of the motor 9 according to the electrical angle, and the control module 1 can judge whether there is overcurrent according to the current value, and then control the drive module 3 to perform corresponding actions;

[0040] The control module 1 comprises: a current detection AD port, which is connected to the output end of the current acquisition module 4 and is used to receive the two-phase current signal of the motor 9 acquired by the current acquisition module 4 .

[0041] Figure 4 is a circuit diagram of the current acquisition module 4 provided in an embodiment of the present invention, such as Figure 4 As shown, the current acquisition module 4 includes: a current sensing amplifier N1. That is, in the present invention, an ultra-precision current sensing amplifier N1 is used to implement current sampling, and the control unit collects two-phase current signals of the motor 9 through two current sensing amplifiers for electrical angle calculation and overcurrent protection, controls the phase change of the motor 9 according to the electrical angle, and outputs a blocking signal after detecting overcurrent, shuts off the output of the drive module 3, and implements overcurrent protection.

[0042] The control module 1 is connected to the host computer 8 via the communication module 5 .

[0043] Figure 5 is a circuit diagram of a communication module 5 provided in an embodiment of the present invention, such as Figure 5 As shown, the communication module 5 is a 232 communication level conversion chip, which is used to realize the conversion between the TTL level and the RS232 level of the control module 1, and to realize the conversion between the TTL level and the RS232 level of the host computer 8.

[0044] Furthermore, a brushless DC motor 9 controller further includes: a bus voltage detection module 6;

[0045] The input end of the bus voltage detection module 6 is connected to the motor 9, and the output end is connected to the control module 1, and is used to collect the bus voltage of the motor 9 and send it to the control module 1, so that the control module 1 can judge whether it is overvoltage or undervoltage according to the voltage value, and then control the drive module 3 to perform corresponding actions (i.e. set the fault state to perform fault processing).

[0046] The control module 1 includes: an overvoltage / undervoltage detection AD port; the overvoltage / undervoltage detection AD port is connected to the output end of the bus voltage detection module 6, and is used to receive the bus voltage of the motor 9 collected by the bus voltage detection module 6.

[0047] Figure 6 is a circuit diagram of the bus voltage detection module 6 provided in an embodiment of the present invention, such as Figure 6 As shown, the bus power voltage passes through the voltage-dividing conditioning circuit of resistors R1 and R2, and is sent to the overvoltage / undervoltage detection AD port of the control module 1 for AD conversion to obtain the DC bus voltage value. When overvoltage or undervoltage is determined based on the voltage value, the fault state is set for fault processing.

[0048] Furthermore, a brushless DC motor 9 controller further includes: a temperature detection module 7;

[0049] The input end of the temperature detection module 7 is connected to the motor 9, and the output end is connected to the control module 1, for collecting the temperature of the motor 9 and sending it to the control module 1, so that the control module 1 determines whether it is overheated according to the temperature value, and then controls the driving module 3 to perform corresponding actions.

[0050] The control module 1 comprises: a temperature detection AD port; the temperature detection AD port is connected to the output end of the temperature detection module 7 and is used to receive the temperature value of the motor 9 collected by the temperature detection module 7 .

[0051] Figure 7 is a circuit diagram of the temperature detection module 7 provided in an embodiment of the present invention, such as Figure 7 As shown, the temperature detection module 7 uses the motor 9 chip temperature sensor RT1, and the temperature sensor RT1 and R1 are connected in series with the resistor to divide the voltage to 3.3V and then sent to the temperature detection AD port of the control module 1 for AD conversion to obtain the temperature value. When overheating is determined according to the temperature value, a blocking signal is output to shut down the output of the drive module 3 to achieve overheat protection.

[0052] Beneficial effects of the present invention:

[0053] The present invention provides a controller for a brushless DC motor 9, which comprises: a power module 2, a control module 1, a drive module 3, a communication module 5, a current acquisition module 4, a bus voltage detection module 6 and a temperature detection module 7; the control module 1 first drives the motor 9 to rotate through the drive module 3, collects the current signal of the motor 9 through the current acquisition module 4 and sends it to the control module 1, so that the control module 1 calculates the electrical angle of the motor 9 according to the current signal and controls the phase change of the motor 9 according to the electrical angle; it does not require a position sensor, has the advantages of low cost and small size, reduces the space occupation of the equipment, and improves the space utilization rate; and during the rotation of the motor 9, the phase current is detected for current limiting protection, the temperature is detected for over-temperature protection, and the bus voltage is detected for overvoltage or undervoltage protection, which can increase the service life of the motor 9.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A brushless DC motor controller, characterized in that: include: Control module, power module, drive module, current acquisition module and communication module; The power module is electrically connected to the control module and is used to supply power to the control module; The control module is connected to the motor through the driving module, and is used to drive the motor to work; The input end of the current acquisition module is connected to the motor, and the output end is connected to the control module, and is used to collect the current signal of the motor and send it to the control module, so that the control module can calculate the electrical angle of the motor according to the current signal and control the commutation of the motor according to the electrical angle, and the control module can judge whether there is overcurrent according to the current value, and then control the driving module to perform corresponding actions; The control module is connected to the host computer through the communication module.

2. The brushless DC motor controller according to claim 1, characterized in that: Also includes: Bus voltage detection module; The input end of the bus voltage detection module is connected to the motor, and the output end is connected to the control module. It is used to collect the bus voltage of the motor and send it to the control module, so that the control module can judge whether it is overvoltage or undervoltage according to the voltage value, and then control the drive module to perform corresponding actions.

3. The brushless DC motor controller according to claim 2, characterized in that: Also includes: Temperature detection module; The input end of the temperature detection module is connected to the motor, and the output end is connected to the control module, and is used to collect the temperature of the motor and send it to the control module, so that the control module determines whether it is overheated according to the temperature value, and then controls the driving module to perform corresponding actions.

4. The brushless DC motor controller according to claim 3, characterized in that: The control module includes: an overvoltage / undervoltage detection AD port, a temperature detection AD port, a current detection AD port and a PWM generator port; The overvoltage / undervoltage detection AD port is connected to the bus voltage detection module; The temperature detection AD port is connected to the temperature detection module; The current detection AD port is connected to the current acquisition module; The PWM generator port is connected to the driving module.

5. The brushless DC motor controller according to claim 1, characterized in that: The control module is an ARM chip.

6. The brushless DC motor controller according to claim 1, characterized in that: The power supply module includes: a power supply, a DC48V / 12V conversion submodule, a DC12V / 5V conversion submodule, and a DC12V / 3.3V conversion submodule.

7. The brushless DC motor controller according to claim 1, characterized in that: The driving module includes: a dual-input gate driving chip and an NMOSFET tube; The dual-input gate drive chip is connected to the motor via an NMOSFET tube.

8. The brushless DC motor controller according to claim 1, characterized in that: The current acquisition module includes: a current sensing amplifier N1.

9. The brushless DC motor controller according to claim 3, characterized in that: The temperature detection module is a temperature sensor RT1.

10. The brushless DC motor controller according to claim 1, characterized in that: The communication module is a 232 communication level conversion chip, which is used to realize the conversion between the TTL level and RS232 level of the control module and the host computer.

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