This design takes STC89C52RC single chip computer as the control core, adjusts the motor speed by keys, then transmits the speed control instruction to STC89C52RC single chip computer for processing, and displays the theoretical value of DC motor speed through LCD1602 display, then processes it by STC89C52RC minimum system, thermostatic element and inputs the signal into L9110H DC motor driving mode. Block, and then through L9110H module to adjust the speed of DC motor, so as to achieve intelligent control of DC motor, and then through Hall element OH137 to measure the actual speed, and the measurement results are sent to LCD1602 display by STC89C52RC single-chip computer, so that the speed of the motor automatically changes with the change of instructions, to achieve height. Sensitive speed control. Since the beginning of the new century, human science and technology have developed continuously and become more and more brilliant. More and more advanced science and technology have promoted the development of all walks of life, and the development of control technology is particularly prominent.
All kinds of control equipment are not only innovative in structural renovation, but also constantly improving and perfecting in performance. Now we are fortunate to be in the information age of rapid development, and control technology is the mainstream technology of this era, not only in daily household appliances and consumer electronic products (such as washing machines, television, air conditioning, etc.), but also in the production and development of travel tools, health equipment, spacecraft, primary and secondary industries. Exhibition, daily working facilities, a variety of controller applications can be seen everywhere.
At the same time, reliable data show that more than 90% of our power resources in life come from motors. It can be seen that the application of motor controller is closely related to our life. In fact, there have been many simple control applications for motors. The so-called simple control, in fact, refers to the simple control of the motor’s opening, front and back rotation direction and order. This kind of control is easy to operate, mainly through relays, programmable controllers and switching elements to achieve functions. Obviously, compared with simple control, there is a kind of control named complex control, which means to control motor on the basis of controlling physical variables such as speed, angle, torque, voltage, current, power and so on. In China’s domestic market, machinery and equipment manufacturing industry is developing vigorously. It can not only meet the needs of machinery and equipment in its own market, but also play a very important role in the foreign market, which is indispensable in the international market. In application, in life, all walks of life, such as medical treatment, automobile manufacturing, railway transportation, aerospace and aviation, steel production, logistics distribution, beverage production and so on, are inseparable from this technology. As we all know, the progress of science and technology is endless. For this reason, further learning, mastering and developing application control technology is our eternal theme, constantly innovating science and technology, so as to improve the quality of life and enhance the international status of our country.
According to the design task, the design of a single chip STC89C52RC MCU is the core, which is composed of input module, display module, power module, drive module and DC motor module.
Two rebound key keys are set in the input to increase or decrease the control of rotation rate, so as to realize the positive of DC motor. To turn, reverse turn, stop, accelerate and decelerate, the specific realization is as follows: each button is added or subtracted at the speed of 100 r/min, when the speed is negative, the DC motor is positive; when the speed is positive, the motor is reversed; when the speed is 0 r/min, the motor is stopped; the display module is set up to display the theoretical value and the actual value separately, which can be real-time accurate. The errors between the two values are compared. Scheme 1: Driver chip L9110H, which is designed to control the direction and speed of motor rotation and improve the power of motor rotation, has two channels, can amplify power and is a highly integrated circuit module with professional function.
It also has relatively separate circuit parts, and is mainly integrated in a single chip. The IC has the advantages of high driving capability, simple peripheral circuit, low cost and high reliability. Scheme 2: Resistance network or digital potentiometer are selected to adjust the rotation direction and speed of DC motor by controlling the local voltage of the motor. Scheme 3: Use relay to control the switching and switching of DC motor by controlling a series of states such as disconnection and closure of relay. Relay is an electronic control device, which uses smaller current to control the effect of larger current. At present, in use, it is equivalent to an “automatic switching device”. Usually, it is mainly used to realize the automation of circuit control. It has control system and controlled system. For the above three schemes, if we choose the second one, because the price of digital resistance components is expensive, the main reason is that the resistance of the motor is generally small, but the current is very large, so after voltage dividing, it not only does not improve the efficiency, but also adds difficulty to the realization of the design; for example, the third one, although the circuit design of the scheme is relatively simple, but also increases the difficulty of the design. And the relay in the circuit has the advantage of automatic regulation, can play a safe protection circuit and equipment system, and automatically realize circuit rotation and transformation and other functions, but to a certain extent, there are relay response to the whole process of service response, the reaction time is relatively slow, and the same.
There are some shortcomings such as fragile structure, short service life and low reliability. Therefore, considering various factors, the design of DC motor controller system adopts the first scheme of the above scheme. This design is based on the design of DC motor controller of SCM. The overall design of the system takes STC89C52RC SCM as the control core. The overall design is shown in Figure 1. In this system scheme, STC89C52RC MCU is used as the control core, the motor speed is adjusted by keys, then the speed control instruction is transmitted to STC89C52RC MCU for processing, and the theoretical value of DC motor speed is displayed by LCD1602 display, then processed by STC89C52RC minimum system, and the signal is input into L9110H DC power.
The motor drive module adjusts the speed of DC motor through L9110H module, so as to realize the intelligent control of DC motor. Then the actual speed is measured by Hall element OH137, and the measured results are sent to LCD1602 display by STC89C52RC single chip computer. Thus, an intelligent control module of DC motor is established.
The speed of the motor changes automatically with the change of the command to achieve a highly sensitive speed control. This design mainly through two buttons: acceleration and deceleration buttons, so as to realize the forward and reverse rotation of DC motor, and the forward and reverse rotational speeds can be from low to high or from low to high, and change randomly between 0-3000 r/min. In addition, in this software design, users can also control the power switch by setting the speed of DC motor, that is, when the speed of DC motor is 0 r/min, the motor executes the stop instruction. It is precisely because the thyristor rectifier has many advantages, naturally this new generation of thyristor DC speed control system replaces the old DC motor controller with various shortcomings, including the mercury rectifier and generator-motor set in front of it. Driven by the development of science and technology, the control circuit is constantly developing and innovating. Not only are DC motor controllers innovative, but also the development of control circuits is constantly improving, especially in its volume, integration, reliability and cost. As a result, the application of DC speed regulation system is more extensive, and driven by the development of science and technology, DC motor control technology will also continue to develop.