Speed Control Of Asynchronous Motor Research Articles

Main Circuit Parameter Stability Region of Induction Motor Speed Control System Based on BBMC

Asynchronous motor speed control system based on Buck-Boost matrix converter ( BBMC ) has good speed regulation performance. Because the inverter stage of BBMC is a variable structure and nonlinear system, BBMC will produce bifurcation and chaos with the change of parameters, resulting in an unstable state of the system. The main factors affecting the stability of BBMC are the main circuit and control parameters. The control parameters can be continuously optimized in the later stage, and the main circuit parameters cannot be changed once they are determined. This paper studies the stability region of main circuit parameters, and the discrete iterative mapping model of the asynchronous motor speed control system based on BBMC is established. According to the sampling distribution of BBMC output voltage, the influence of main circuit parameters inductance L and capacitance C on the stability of the speed control system is analyzed. The stability region of the main circuit parameters is determined by numerical fitting. Finally, simulation and experiment verify the above analysis’s correctness. The stability region of main circuit parameters can provide the basis for selecting main circuit parameters in practical engineering.

Control Parameter Stability Domain of BBMC Speed Control System with Finite-Time Control

The buck-boost matrix converter (BBMC) asynchronous motor speed control system based on finite time control has a good speed control performance, but its system stability is closely related to the selection of its control parameters. Therefore, a method for determining the stability region of control parameters is proposed. The discrete iterative mapping model of the BBMC speed control system is established, and the control function of the BBMC speed control system based on finite time control is determined. The BBMC output voltage sampling distribution diagram is used to analyze the influence of each control parameter in the finite time control on the stability of the speed control system. On this basis, the study determined the value range of each control parameter to realize the stable operation of the system. Finally, the correctness of the above theoretical analysis was verified through the BBMC output voltage waveform diagram and experiments. The stability region of control parameters can effectively ensure the stable operation of BBMC speed control system based on finite time control.

Vector control system design for asynchronous motors

In order to decouple the excitation and torque components of the stator current so that the asynchronous motor speed control system approximates a DC speed control system. Firstly, the asynchronous motor model is transformed in coordinates, and then the vector control idea is proposed to construct a vector control system for the asynchronous motor. At the same time, a simulation model of the vector control system of an asynchronous motor was created on the Matlab platform and the speed waveform was recorded. The analysis of the experimental data showed that the speed response of the vector control system was fast and smooth, which improved the performance of the asynchronous motor speed control system.

Adaptive PID Control with Forgetting Factor for Three-phase Asynchronous Motor

In order to solve these problems of large overshot and poor stability of the speed-control loop for a three-phase asynchronous motor, one adaptive PID controller is applied. The controller combines least square method with forgetting factor to estimate such PID control parameters, which can adjust PID controller’s parameters in real time even when some abrupt disturbance occurs. The simulation results show that the proposed adaptive PID controller has some advantages, such as fast response, good stability, certain adaptability and robustness, compared with traditional one, and can meet the basic requirements for the speed control of asynchronous motor.

Speed control of asynchronous motor based on improved deadbeat predictive algorithm

In this article, the three-phase asynchronous motor is taken as the research object, and the deadbeat predictive control is the control core, and its control performance is studied. Considering the overshoot of flux linkage and speed response in deadbeat predictive control, an improved deadbeat predictive control algorithm based on synergy theory is proposed. Different from deadbeat predictive control, improved deadbeat predictive control can control the flux linkage and speed independently through two adjustment parameters, which are achieved through the manifold of synergy theory. To accurately obtain the feedback flux linkage and load torque in the control, a flux observer and a load torque observer are designed. Based on these, a simulation platform is built, and the control performance of the two control algorithms is compared. The robustness of the two control algorithms is further verified by changing parameters. Finally, the experimental platform of three-phase asynchronous motor is built in this article. The experimental program based on deadbeat predictive control is designed. The no-load experiment and loading experiment are carried out, respectively. The feasibility of the algorithm is verified by experimental data.

A Low cost modelling of the variable frequency drive optimum in industrial applications

A single or three phase asynchronous motors, or known a squirrel cage motors (SCMs) are represent one of generally using in many industrial applications. They are consuming further than half-percent of the total generated electrical energy. This motor is working at its full speed when it is attached to the main AC- supply. Therefore, speed control of asynchronous motor is necessary to industrial applications that require changeable flow control of fluid (air, water and chemical liquid streaming). There are many methods to control the speed of motors, such as changing the stator number of poles, controlling supply voltage, addition series reactor or resistances. The modern method is Volt per Hertz, or scalar control this method applied by changing voltage and frequency of three-phase supply, or by making a V/f equal to a constant value in this method a large amount of energy can be saved. In this study, analysis and practical implemented to variable voltage Variable Frequency Drive or called a VFD. The model enables an exception of a large amount of energy, when connected to control speed of Induction motor. A new simplified method for implemented of an AC Drive system with a moderate price for components was proposed. This method totally based on assembling overall components of AC-Drive. The advantage of this design is simplicity, robustness and ease of tuning as well as manufacturing due to these advantages. This design is very suitable for real time applications as motor speed controller. The experimental results obtained show that design helps to preserve a large amount of energy to the power grid, by a limited starting current of the motor as well, eliminating a voltage flicker at starting and reducing dissipating power during running in long period. Results verified experimentally.

Sensorless Speed Control of Synchronous Motors: Analysis and Mitigation of Stator Resistance Error

Direct torque control-based sensorless speed control (DTC-SSC) of a synchronous motor is a high performance and reliable approach for the control of speed and stator flux modulus. This paper proposes an analytical method to study the effect of error in estimation of stator resistance on the stability of a synchronous motor controlled via DTC-SSC approach, a reliable resistance estimator based on the angle between the stator flux and current vectors with no need to solve nonlinear equations, and a modified structure for sensorless speed control of synchronous motors based on this estimator. Simulation and experimental case studies validate the proposed stability analysis and the resistance estimator.

The Design of the Vector Control System of Asynchronous Motor

Among various modes of the asynchronous motor speed control, vector control has the advantages of fast response, stability, transmission of high-performance and wide speed range. For the need of the asynchronous motor speed control, the design uses 89C196 as the controller, and introduces the designs of hardware and software in details. The Design is completed effectively, with good performance simple structure and good prospects of development.