Abstract
DC speed regulation system plays an important role in industrial control because of its smooth speed regulation performance and wide application range. Among them, the control effect of the double closed-loop structure is the best. This paper deeply discusses the composition structure and dynamic structure diagram of the double-closed-loop DC speed control system, and uses the engineering design method to design the structure and parameters of the current regulator and the speed regulator. Finally, through Simulink modeling and simulation, it is proved that the parameter design is reasonable and effective, and can achieve the ideal speed regulation effect.
Key words: speed loop; current loop; PI regulator; SIMULINK
Abstract
Because of its performance suitable for smooth speed regulation in a wide range, the DC speed control system has always played an important role in industrial control. The control effect of the DC speed control system is the best when the double closed-loop structure is used. For this reason, the double closed-loop DC speed control system is studied, the system structure is explained, the dynamic structure diagram of the system is analyzed, and the current regulation is designed using the engineering design method. Finally, Simulink is used to model and simulate the double closed-loop speed regulation system of DC motor. The simulation results show that the parameters of the speed regulator and current regulator are designed reasonably and can achieve the ideal speed regulation effect.
Key words:loop of revolution rate;loop of current;regulator;simulink
Table
of Contents Abstract II
Abstract III
1 Introduction 1
1.1 Research Significance 1
1.2 Current Research Status at Home and Abroad 1
1.3 Main Research Contents of this Paper 2
2 Composition and Dynamic Analysis of Double Closed-loop DC Speed Control System 3
2.1 Structural Composition of Double Closed-loop DC Speed Control System 3
2.2 Dynamic process analysis of double closed-loop DC speed control system 5
3 Engineering design of double closed-loop DC speed control system 7
3.1 Engineering design steps of double closed-loop DC speed control system 7
3.2 Engineering design example of double closed-loop DC speed control system 7
4 Double closed-loop DC Simulation research of speed control system 11
4.1 Modeling of double closed-loop speed control system based on Simulink 11
4.2 Theoretical analysis of simulation results 11
4.3 Simulation and analysis of different working conditions (including fault conditions) 14
4.4 Thinking of power conversion device (whether to simplify It is the first-order inertial link) 25
4.5 Frequency-domain hysteresis correction related knowledge of automatic control principle to realize dynamic design 26
4.6 Simulation of double closed-loop DC speed control system based on electrical schematic diagram 33
5 Summary 35
Acknowledgments 36
References 37
1 Introduction
1.1 Research Significance
DC motor plays an important role in industrial control because it is suitable for stable speed regulation in a wide range. Among them, the speed and current double closed-loop speed control system is the most typical one. Simulation technology is an important tool to study and analyze various systems, especially complex systems, and has been widely used in today's society. Therefore, using the SIMULINK utility tool in Matlab to simulate and analyze the double closed-loop speed control system of the DC motor has become a topic that we need to discuss urgently. This method can make the engineering design and solve the difficulties that may arise in the design easier.
Study the control strategy of the DC speed control system: Through modeling and simulation, different control strategies of the DC speed control system, such as PID control, can be studied and analyzed, so as to select the optimal control strategy. Debugging and verification of system parameters: Through modeling and simulation, it is possible to debug and verify the DC speed control system, especially to adjust and optimize the system parameters to obtain better performance and stability. Optimizing system control performance: Through modeling and simulation, the control performance of the DC speed control system can be studied, such as response time, steady-state error, etc., and optimized to achieve better control effects. Reduce experimental costs and risks: Through modeling and simulation, experiments can be carried out on computers, which avoids the costs and risks of purchasing, maintaining, and transporting experimental equipment, and can greatly shorten the experimental cycle.
1.2 Research status at home and abroad
Since the middle and late 1980s, the digital speed control transmission system has developed to a very advanced level, and major electric companies in the world are competing to develop it. Thyristors are used for power components, surface mount technology is used for control boards, and the two control methods of power commutation and phase control are used for control. Using microcomputer and other advanced technology, the digital DC speed control device has very high electronic resolution, good electronic digital operation performance and strong ability to resist other sources. These technologies are widely used at home and abroad. Now, the advanced electrical speed control system has realized informatization in developed countries, and the double closed-loop control system has been widely used in the production process of various instruments and meters, mechanical heavy industry and light industry. With the development of global science and technology, the current development trend of the double closed-loop control system is to develop in the direction of control informatization, artificial intelligence and big data. As the transmission method with the latest degree of control, the full digital DC speed control device shows the powerful advantages of the full information DC speed control device. The electronic information DC speed control system has been evolving, and the engineering application has obtained rich advantages. Domestic scholars have carried out in-depth research on the double closed-loop DC speed control system from two aspects of theory and experiment. Among them, the theoretical aspect mainly discusses the DC motor and its control principle in depth, and proposes a DC motor control simulation platform based on MATLAB; the experimental aspect mainly conducts experimental research on the speed control system of the DC motor, discusses different The speed regulation control strategy and parameter optimization method improve the control accuracy and robustness of the system.
Foreign researchers have also conducted extensive research on double closed-loop DC speed control systems. Among them, the theoretical aspect is mainly to conduct in-depth research on the control principle and control strategy of the DC motor, and some new control methods and algorithms are proposed; the experimental aspect is mainly to analyze and optimize the system by establishing a simulation model, and improve the system. control performance and stability. At the same time, some DC motor controllers and control software have been developed to facilitate the control of DC motors.
With the advancement of science and technology and the continuous development of motor control technology, the modeling and simulation research of double closed-loop DC speed control system is also deepening and expanding. Future development trends mainly include the following aspects: (1) Optimization of control strategies: Researchers will be committed to proposing more optimal control strategies to improve the control accuracy and robustness of the system, such as control strategies based on artificial intelligence. (2) Innovation of hardware platforms: researchers will develop more advanced hardware platforms to meet the needs of practical applications in different environments, such as embedded hardware. (3) Improvement of the system simulation model: researchers will establish a more complete simulation model to more accurately simulate the operation of the actual system. (4) Interdisciplinary research: Researchers will learn from the research results of other disciplines, such as control theory, mechanical design, electronic technology, etc., so as to further improve the control performance and stability of the system. In short, the modeling and simulation research of double closed-loop DC speed control system will be more in-depth and extensive in the future, injecting new vitality and impetus into the development of this field. The double closed-loop DC speed control system has a wide range of application scenarios in practical applications, such as electric vehicles, elevators, wind power generation, water pumps, machine tools and other fields. Among them, electric vehicles are one of the most representative application scenarios. By optimizing and improving the double closed-loop DC speed control system of electric vehicles, the power performance and energy saving effect of electric vehicles can be improved, so as to better meet the needs of users. In the future, the development prospect of double closed-loop DC speed control system is very broad. With the continuous advancement of science and technology and the continuous expansion of applications, the double closed-loop DC speed control system will be used in a wider range of fields, such as intelligent manufacturing, intelligent transportation, smart home, etc., to bring more convenience to people's life and work and benefits. At the same time, with the rapid development and popularization of electric vehicles, the double closed-loop DC speed control system will also be more widely used and promoted, becoming an important part of the electric vehicle industry.
To sum up, researchers at home and abroad have carried out a lot of research on the modeling and simulation of double closed-loop DC speed control systems, which provides strong support and impetus for the further development of this field.
With the R & D and improvement of the central cluster computer, foreign research on DC speed control systems is also constantly improving and upgrading. Researchers have proposed algorithms of fuzzy PID algorithm, adaptive PID algorithm, internal model control algorithm and IP controller to replace PI regulator. Thyristor trigger pulses are generally used in speed regulation systems of large DC motors. Foreign front-line technology electrical appliance groups, such as ABB, Siemens, AEG, Mitsubishi, Toshiba, GE, and Westinghouse, have developed a number of digital DC speed control devices, including many successful standardized, serialized and templated application products. These achievements also provide strong support and impetus for the development of DC speed control system.
1.3 Main research content of this thesis
Modeling of DC motor: abstract DC motor into a mathematical model, and use equations to describe its dynamic characteristics, including parameters such as electromagnetic torque, motor speed and current of the motor. The design of the speed loop controller: the speed regulation of the motor is realized by controlling the speed of the motor, and the speed loop controller is the key to realize this goal. The design of the current loop controller: the torque control of the motor is realized by controlling the current of the motor, and the current loop controller is the key to realize this goal. Modeling of the double closed-loop control system: the speed loop and current loop controllers are combined to establish the mathematical model of the double closed-loop control system. Simulation of control algorithm: Use simulation software such as MATLAB to simulate the control algorithm to test the performance and stability of the control algorithm. Optimization of system parameters: Through the simulation platform, optimize the system parameters to improve the stability and control performance of the system.
In short, the main research content of the modeling and simulation of the double closed-loop DC speed control system is to combine the motor, controller and simulation software to establish a mathematical model and simulation platform to optimize system parameters and improve control performance.
System steady state and dynamic performance target performance are the basis for designing electric drive control system. The steady-state target reflects the accuracy and adjustability of the system, the overshoot in the following performance reflects the relative stability of the system, the rise time reflects the rapidity of the system, and the dynamic drop in the anti-disturbance index reflects the rapidity of the system's adjustment performance. These can be summed up as "stable, accurate, fast" three words. On this basis, it is necessary to comprehensively deal with various conflicts, including selecting appropriate control laws and methods, innovating the system and coordinating the financial nature of the entire device. In order to improve the reliability of the system, the DC motor speed control system can be designed, and the reasonable reliability of the system design can be judged through the measurement and analysis of performance indicators. The DC motor speed control system is a high-order system, and its design is relatively complicated. When designing, it is necessary to comprehensively consider various factors and choose a reasonable order. The basic idea of the design method is to select the structure of the regulator to ensure the stability and steady-state accuracy of the system first, and then select the parameters of the regulator to meet the dynamic performance index. In the design of the double-loop speed control system, usually start from the current loop to design the current regulator, and then use the entire current loop as an equivalent link in the speed regulation system to design the speed regulator. In order to study the characteristics of the DC speed control system and analyze the design requirements of the system, MATLAB can be used for simulation. In this thesis, a double closed-loop DC speed control system is designed, and both regulators are designed as PI regulators. Through the simulation analysis, the optimal control of the DC speed control system is discussed.
