Advanced Speed Control Techniques of Brushless Dc Motor
Transcript of Advanced Speed Control Techniques of Brushless Dc Motor
DIRECT TORQUE CONTROL OF BRUSHLESS DC MOTORS
OBJECTIVE
To control the speed of three phase brushless dc motor by using Direct torque control principle.
To find some satisfactory solution for the problems that arise in applying Direct torque control principle.
To introduce new optimization techniques for improving the performance of Direct torque controlled Brushless DC motor drive.
CLASSIFICATION OF MOTORS
BRUSHLESS DC MOTORSBrushless Direct Current (BLDC) motor
one of the type of synchronous motor. BLDC motors do not use brushes for
commutation; instead, they are electronically commutated.
BLDC motors are used in industries such as Appliances, Automotive, Aerospace, Consumer, Medical, Industrial Automation Equipment and Instrumentation.
ADVANTAGES OF BLDC MOTOR
BLDC motors have many advantages over brushed DC motors and induction motors.
A few of these are: Better speed versus torque characteristics High dynamic response High efficiency Long operating life Noiseless operation Higher speed ranges
DISADVANTAGES OF BLDC MOTOR
Cost of Permanent Magnets
Need for Position Sensors
Limited Extended Speed Range
Field Weakening Operation is Difficult
MODELING OF BLDC MOTOR
SPEED CONTROL TECHNIQUES
DIRECT TORQUE CONTROL
FEATURES OF DTC SCHEME
Direct torque control and and direct stator flux control
Indirect control of stator currents and voltage
Approximately sinusoidal stator flux and stator currents.
High dynamic performance
ADVANTAGES OF DTC SCHEME
Absence of co-ordinate transformation
Minimal torque response time.
DISADVANTAGES OF DTC SCHEME
• possible problems during starting
•Inherent torque and flux ripples
optimizationOptimization is one of the acute
problem in science and technology.
Several optimization techniques are there like
1. Genetic algorithm2. Simulated analysis3. Swam optimization4. Ant colony algorithm
Contd.. Reason for choosing bacteria
foraging optimization ?
Bacteria foraging optimization- the most primitive organisms to be dealt for global optimization.
Swam foraging in adaptive control
Software for implementation
The total direct torque control of BLDC motor is simulated using MATLAB / SIMULINK software