DC

DC motor is one of the main types of motors. Due to its good speed regulation performance, it is widely used in many occasions with high speed regulation performance requirements. DC motors are also widely used in electronic production.

When the load is constant, the greater the average current flowing through the DC motor, the greater the torque generated, and thus the faster the speed of the DC motor; when the current is constant, the greater the load, the slower the speed of the DC motor.

#Drive of DC motor
1. Linear amplifier drive
The linear driver is actually a linear power amplifier, and the principle is as follows. The control signal output by the processor is converted into a voltage signal by D/A, and the driver performs linear power amplification on this signal and provides it to the motor. Since the current and voltage drop passing through the driver are relatively large, the biggest disadvantage of this driving method is high power consumption and low efficiency. However, since there is no high-frequency switching action in the linear power amplifier, the output voltage is stable, and compared with switching drive methods such as PWM, the electromagnetic noise and interference are much smaller.

2. Switching driver

Switch drive uses the switching action of high-power transistors to convert the constant DC power supply voltage into a certain square wave voltage and add it to the motor pivot. Different from the linear drive mode, in this drive mode, the power tube of the driver works in a switching state. When the device is turned on, the current of the device is large but the voltage drop is small; when the device is turned off, the voltage drop is large but the current is small. Therefore, the driver has low power consumption, low heat generation and high efficiency. By controlling the frequency and pulse width of the switch, the rotation of the motor can be controlled.

#DC motor switch drive circuit
There are two main types of DC motor switch drivers, T-type irreversible driver and H-type reversible driver

Principle explanation to be supplemented!

experiment

#Code

* 【Course 21】 ****DC Motor Experiment***********

*

* 【illustrate】 ****

*

* 【Description】 ****Realize the forward, reverse and stop of the motor.

*

**********************************************************************/

#include //51 header file,

//---------Two commonly used macro definitions-------------- 

#define uint8 unsigned char

#define uint16 unsigned int

sbit Motor_A = P1^0;

sbit Motor_B = P1^1;

sbit Key1 = P3^0; //Forward

sbit Key2 = P3^1; //Reverse

sbit Key3 = P3^2; //Stop

//------------Function declaration-----------------

void DelayMS(uint16 dly);

void main(void)

{

while(1)

{

/*if(Key1==0) //Forward

{

Motor_A = 0;

Motor_B = 1;

}

else if(Key2==0) //Reverse

{

Motor_A = 1;

Motor_B = 0;

}

else if(Key3==0) //Stop

{

Motor_A = Motor_B = 0;

}

*/

Motor_A = 0;

Motor_B = 1;

DelayMS(9);

Motor_A = 0;

Motor_B = 0;

DelayMS(1);

}

}

/********************************************************

** Name: void DelayMS(uint16 dly)

** Function: millisecond delay (24M crystal oscillator)

** Input parameter: dly

User delay parameters   

** Export parameters: None   

*************************************************************/

void DelayMS(uint16 dly)

{

uint16 x,y;

for(x=dly;x>0;x--)

for(y=247;y>0;y--);

}