Speed control of separately excited dc motor by ppt 2 free download as powerpoint presentation. Transfer function is obtained by conducting the speed control test on the dc shunt motor 2. The name suggests the construction of this type of motor. The system consists of dc dc buck converter to drive the dc motor. Dc motor principle a machine that converts dc power into mechanical energy is known as dc motor.
A antiwindup technique is used in controller to avoid integrator windup problem. Mathematical modeling of systems in this chapter, we lead you through a study of mathematical models of. The fourth connection, separatelyexcited, can be made to respond like any of the other three by proper control of the excitation voltage. Figure below depicts the electrical and mechanical model of a typical shunt wound, separately excited dc motor. Mathematical model of a separately excited dc motor powered. What is common to all the members of this family is that the basic. Pid controller tuning using zieglernichols method for. Pdf speed control of separately excited dc motor using. The proposed method, is very efficient and could easily be extended for other global. This paper focuses on the study of dc motor linear speed control, therefore, the separately excited dc motor is adopted.
Modeling, analysis and speed control design methods of a. For the original problem setup and the derivation of the above equations, please refer to the dc motor speed. Index terms direct current motor, optimal efficiency. Different speed can be obtained by changing the armature voltage and the field voltage. Identify and utilize equations that represent motor performance to solve separately excited dc motor problems. In general an accurate nonlinear model of an actual dc motor is difficult to. Many situations demand change in the speed of the dc motor. Equivalent circuit of shunt wound separately excited dc motor m. The design method uses the concepts of the system theory, such as signals and systems, transfer functions, direct and inverse laplace transforms. Generally, an accurate nonlinear model of an actual dc. Separately excited dc motor speed control of using various. In order to measure the time response of a dc motor it is necessary to obtain transfer function of the dc motor. The rest of the paper is presented at first the dc separately excited motor mathematical model is described.
However, the performance of these methods depends on the accuracy of system models and parameters. The main distinguishing fact in these types of dc motor is that, the armature current does not flow through the field windings, as the field winding is energized from a separate external source of dc current as shown in the figure beside. Draw a circuit model of a separately excited dc motor. The proper design of closed loop control system depends heavily upon an adequate mathematical model for the most basic component dc motor. Modeling and simulation of the dc motor using matlab and labview. In section v, experimental results are illustrated and compared to the simulation results.
What is common to all the members of this family is that the basic physical process involved in their operation is the conversion. A comparative study of the model for the separately excited dc motor has shown that the models have their. In a brushed dc motor, the coils on the rotor utilize the motors magnetic eld. Dc motor mathematical model this dc motor system is a separately excited dc motor 7, which is often used to the velocity tuning and the position adjustment. This research article proposes the speed control of a separately excited dc motor sedm in the constant torque region. Write a power balance for a separately excited motor and compute its efficiency. The purpose is to achieve accurate trajectory control of the. Types of dc motors and their applications electrical4u. Close loop control is done in two loop, first inner current loop having currenttorque controller and outer speed controller loop control the speed. The objective of this paper is to describe the principle of dc motor speed control using. Dc motors are widely used in industries for various purposes. Zieglernichols method for separately excited dc motor speed control, which leads to improve the transient and steady state of speed responses of separately excited dc motor. This makes it a necessity to employ a method to effectively control the speed of a separately excited dc motor. Usually, in other dc motors, the field coil and the armature coil both are energized from a single source.
The separately excited dc motors are most often used. Ssrg international journal of electrica l and electronics engineering ssrgijeee volume 1 issue 6 august 2014 issn. The rotor speed of the dc motor can be made to follow an arbitrarily selected trajectory. In addition the result obtained shows that at different input voltages, the speed the dc motor is inversely proportional to the load torque. The purpose is to achieve accurate trajectory control of the speed of saperately excited dc motor, especially when the motor and load parameters are unknown. This is fine as it shows me that the motor is running aroud 50%. A good material for the poles of a pmdc motor should have the apposite of the above. In this paper speed control of the dc motor by armature control method is proposed.
Mathematical modeling and speed control of bldc motor. In a brushed dc motor, the coils on the rotor utilize the motors magnetic eld to create torque on the axle. Dc motor model dc motor testing in order to develop a model of the entire super cart for simulation purposes, a model of the dc motor had to be developed. For instance, 4, 5 present a mathematical formulation to describe a separately excited dc motor powered by solar arrays without considering the control system. Its operation is based on the principle that when a current carrying conductor is placed in a. Dynamic modeling, simulation and control of electric machines. Modeling, analysis and speed control design methods of a dc motor. The resistances and inductances of the field and armature sides of the motor are.
For a 1radsec step reference, the design criteria are the following. Moment of inertia of the motor rotor with attached mechanical load, j 0. A new speed control technique for a separately excited direct. Mathematical modeling and speed control of bldc motor using ga and pid 1prachi sahu, 2ashish sahu. I seem to be stuck on the efficiency vs torque of the motor. Model equations the dc motor for the suvln is a separately excited. Speed control of a separately excited dc motor engineering essay. As the name suggests, in case of a separately excited dc motor the supply is given separately to the field and armature windings.
A field controlled dc motor is a separately excited dc motor where the field current controls the motor torque. Design and simulation of neuro fuzzy controller for speed. Comparative study of speed control of separately excited dc motor using pi controller and fuzzy logic controller. The dc motor which is typically employed in electromechanical systems such as weigh feeder for low speed control also has significant friction. Speed control of separately excited dc motor moleykutty george. Simulation used in education for a separately excited dc motor. The mathematical model of the motor and neural network algorithm is derived. Finally, conclusions of the paper are summarized in section vi. Study of nonlinear behavior of dc motor using modeling and. The control strategy is explained and the control circuit is proposed. Oct 17, 2014 mathematical modeling and close loop speed control of separately excited dc motor.
Dc motor model the dynamic of the separately excited dc motor may be expressed by the following equations u t dt di t k t r i t l a a. The next section describes and designs the lqr technique. High starting performance separately excited dc motor. Pdf modeling and simulation of the dc motor using matlab. This requires building the appropriate laplace model for each component of the whole control system. Electric vehicle modeling utilizing dc motor equations. System analysis page where the systems openloop response is simulated. Separately excited dc motor has field coils similar to that of shunt wound dc motor. A mathematical model of the process has been developed using real plant data and then conventional controllers and fuzzy logic controller has been designed. How to mathematically model a dc shunt motor coupled to a dc. Dynamic modeling, simulation and control of electric. The first task was to contact the manufacture in order to obtain as much information about the motor as possible. Speed control of a separately excited dc motor engineering. Permanent magnet dc machines in this section, we will consider the first type as a power actuator that delivers.
Simulink separately excited dc motor matlab answers. To design a neuro fuzzy controller for speed control of a separately excited dc motor. Model reference controlled separately excited dc motor. Im doing a lab report for a shunt dc motor evaluation. A comparative study of the model for the separately excited dc motor has shown that the models have their own merits and demerits. Modeling and speed control of separately excited dc motor. Modelling and simulation of armaturecontrolled direct. Speed control of separately excited dc motor by ppt 2. When a separately excited motor is excited by a field current of if and an armature current of ia flows in the circuit, the motor develops a back emf and a torque to balance the load torque at a particular speed. Speed control of separately excited dc motor using chopper. Since the most basic requirement of a motor is that it should rotate at the desired speed, we will require that. The standard simulink model for a dc motor may be used as generator. Speed control of separately excited dc motor using fuzzy.
Mathematical model of a separately excited dc motor. The separately excited brushed dc motor lends easily to simple control, by virtue of the brush commutator which offers decoupled control via. This paper describes the speed control of a dc shunt motor using conventional controllers pid, imc and fuzzy logic controller based on matlab simulation program. From the main problem, the dynamic equations in the laplace domain and the openloop transfer function of the dc motor are the following. The separately excited dc motor is typical and always taught at universities. Motor to be controlled is a separately excited dc motor as shown in figure. Separately excited dc motor optimal efficiency controller ijeit. Direct current motors can be divided into separately excited dc motors, shuntwound dc motors, serieswound dc motors and compoundwound dc motor s. Ecen 2270 electronics design laboratory 15 dc motor spice subcircuit model model parameters to be determined by experiments. The system structure of a dc motor is depicted in figure22, including the. Once a mathematical model of a system is obtained, various analytical and. The novelty of this article lies in the application of artificial neural networkbased model reference controller mrc for the speed control of sedm. Jawaharlal nehru technological university anantapur course structure and syllabus for m.
When operated as a generator, it does the opposite. Modeling of dc motor the most common device used as an actuator in mechanical control is the dc motor. By adding pid controller to block diagram, sedcm has been remodeled. Brushless dc motor is one of a smallscale motor used in small electric devices like cd players, hard disk drives, or even small. If only 10% of the cycles are used to apply a voltage, the pwm signal is said to be set at 10 fig. Other members of the family are the direct current dc motor or generator, the induction motor or generator, and a number of derivatives of all these three. Model a model is any physical or conceptual representation of an actual material or object, to simplify. Time response analysis of dc motor using armature control. The stated curb weight of the vehicle is 794 kg, but 900 kg is used as a loaded vehicle weight in the following analyses.
First consider that our uncompensated motor rotates at 0. For example, the control of a rotary inverted pendulum requires a dc motor to drive the arm and the pendulum as shown in figure 21. The electric motor drive is widely used in industries. In the simple motor model we start off with, the mechanical parameters are completely ignored. Pdf mathematical model of a separately excited dc motor. The model is created by assembling a physical network of simscape components, including electrical resistors, shaft inertias, and friction. Speed control of separately excited dc motor and performance analysis by software simulation has been done.
The significant feature of separately excited dc motor configuration is its ability to produce high starting torque at low operation speed 2. In this paper we propose the use of photovoltaic as a power source for dc motors performing a feasibility analysis of this system using simulink, for which we show the mathematical model of a solar array in combination with a dc motor separately excited, including the boot process. Mathematical model of a separately excited dc motor powered by a solar array using external starter resistances. Described in articlethis is the simulation of a separately excited motor, includingdc starting, speed control and. This paper discusses the speed and torque control of a shunt dc motor through matlab simulink simulations. The system consists of dcdc buck converter to drive the dc motor.
Similarly, the model of the armature winding for this motor is expressed as. Speed control of a dc motor using controllers science. Dc separately excited motor math mathematical model as reference we consider a dc separately excited motor as is shown in figure 1. Measurements and mathematical modeling of a dc motor for the. A comparative analysis of performance evaluation of all controllers has. Electrical machines for mechatronics laboratory 7 4 speed control of series dc motors unlike with the shunt dc motor, there is only one efficient way to change the speed a series dc motor. The set of equations here reported, constitutes a model of the dc motor, which may 6. Separately excited dc motor allows having independent control of both the magnetic flux and the. The solid lines show the mean velocity produced by each pwm signal.
Ssrg international journal of electrica l and electronics. Explain how changing motor load affects efficiency. Starting analysis of separately excited dc motor by pi. Mathematical modeling and close loop speed control of separately excited dc motor. Dc motors although ac motors are used in most of the cases, dc motors have many applications and used for multipurpose applications. The dc motor may be a dc series motor or a dc separately excited motor or a pmdc motor. Brushed dc motor theory and operation chris joyce, shane skikne, evan simpson, james nee january 8, 2014 abstract this study looked into the e ect of changing the material within the rotor of an electric motor. The proposed method, is very efficient and could easily be extended for other global techniques. The simulation results are evaluated in the simscape results explorer. Feb 25, 2018 a dc motor takes electrical energy and converts into mechanical energy whereas a dc generator converts mechanical energy into electrical energy. International journal of engineering trends and technology. The voltages applied to the field and armature sides of the motor are represented byv f and v a.
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