Induction Motor Speed Control Through Vector Control Approach

[Audio] Induction Motor Speed Control Through Vector Control Approach presented by R. madhusudhan reddy pepar id : icscds796.

Topics to be covered : Abstract Introduction Control Methods Control Scheme Simulation Results Conclusion.

Abstract. This paper presents the technique of vector control, often stated to as field-oriented control (FOC), is frequently utilize in Factory made applications to regulate speed and torque of IM drives. Vector control enables precise control of motor speed and torque by segmenting the stator current into components that produce torque and flux. The 3-phase Alternating current(AC) voltage & current signals are altered into a rotating reference frame, where the stator currents are divided into their torque and flux components, to achieve this. A PI controller uses the converted signals to produce the reference values for the torque ( T c ) & flux components of the stator’s current. The inverse Park transform is then used to turn these values back into three-phase signals, which creates the control signals for the motor drive. Keywords: Field oriented control(FOC), PI Converter, inverse park transform ,Vector control, Alternating Current ..

I.Introduction. This paper presents a point which states that Induction motors continue to be most widely used motors in the industry, as is well known, due to their excellent performance and affordable price.[2] Advantageous operational characteristics of AC induction motors include power, durability, and ease of control. They are extensively used in a variety of applications, ranging from mechanical control mechanisms for residential appliances.[1] Despite this, using induction motors at their highest productivity levels is a challenging task because of their complicated numerical representation and non-straight trademark during immersion.[14]These elements lead to acceptance engine control issues and necessitate the use of advanced control computations, such as vector control.[4]Due to their high performance and low price, induction motors continue to be the most popular motors in the industry. It comprises great dependability, low cost, and widespread use in industrial applications, induction motors are practically completely maintenance-free.[10]When compared to a DC motor, it is robust, lighter, cheaper, more reliable, and nearly maintenance-free. The induction motor(IM) can be controlled in a variety of ways. V/f control is the oldest technique used among these.[9].

VC also acknowledged as field oriented control, is a control approach used for achieving high-performance control of induction motors.[15] This technique involves transforming the three-phase AC power supply into a two-phase system, with the first phase being the magnetizing component and the second phase being the torque component.[6] The advantages of vector control include: High performance: Vector control provides accurate and fast control of the motor's speed, torque, and position.[12] Energy efficiency: Vector control minimizes losses in the motor, resulting in improved energy efficiency. Reduced maintenance: Vector control reduces the stress on the motor, resulting in lower maintenance requirements. Increased lifespan: Vector control extends the lifespan of the motor by reducing the stress and wears on its components. In summary, vector control is a powerful control strategy used to achieve high-performance control of induction motors, resulting in improved energy efficiency, reduced maintenance requirements, and increased lifespan.[7].

II.Control Methods. Fig.1. Control for induction motor(IM) using scalar and vector methods..

From figure (2), VC is a procedure used for controlling the speed & torque ( T c ) of IM. The main idea behind this control scheme is to treat the induction motor as a separately excited Direct current motor with a field flux & an armature current. This way, the induction motor(IM) can be controlled as a DC motor, even though it is an AC motor. The vector control scheme involves transforming the 3-phase Alternating Current-voltage and current (I) of the induction motor into 2-phase DC quantities, which can be used for controlling the motor's speed & T c . The transformation is done using Clarke and Park transformations..

III.Control Scheme. Synchronous frame (dc sigwls) Statman' frame (ac Signals) dq/abc Flax.

Fig.4.General Diagram Of Rotor Flux FOC. Field-Oriented Control method named for (FOC) is the control scheme for induction motors that offer a fast dynamic response and high accuracy . Figure 4 shows the General Diagram of Rotor Flux FOC. FOC provides precise control of the motor with a fast dynamic response, which makes it perfectly good for robotics, electric vehicles. FOC has become a popular control scheme for induction motors because of its effectiveness in achieving high torque and speed control. However, FOC requires complex control algorithms and is more expensive than traditional control schemes..

IV.Simulation Results. Fig.6.depicts the waveforms of Voltage ( Vab ), Current ( Iabc ), Rotor speed, Electromagnetic Torque(Te) in induction motor under vector control reference frame..

Fig.7. shows the waveforms of Rotor’s Quadrant current ( Iq ), Direct current (Id) which have a magnitude ranging from +10A to -10A.

Fig.8. describes the waveforms of Stator’s Quadrant current( Iq ),Direct current(Id) which consists of X-axis as Time(sec) and Y-axis as Current(A).The Iq waveform exists in between the -100A to -80A range. And Id waveform lies in between +50A to +75A values..

Fig.9. demonstrates the wave forms of Iabc in which X-axis is taken as Time(sec) and Y-axis is taken as Current(A).It is three phase current waveform in which red coloured waveform is considered as Ia,the blue coloured waveform is considered as Ib,and the yellow coloured waveform is considered as Ic ..

Fig.10. displays the waveform of three phase voltage ( Vabc ).From the figure, we can see that the waveform varies the magnitude ranging from -800V to +800V..

V.Conclusion. In conclusion, VC can be said as Field-Oriented Control is a sophisticated control scheme for induction motors that offers precise control of the motor's speed and torque with high dynamic response and accuracy. The control scheme involves controlling the stator current, rotor flux separately by a mathematical model to estimate motor's parameters Vector Control has been widely adopted in various industrial applications, including electric vehicles, robotics, and machine tools, due to its effectiveness in achieving high performance and efficiency. However, Vector Control requires complex algorithms and additional hardware, which makes it more expensive compared to other control schemes. Nonetheless, the benefits of Vector Control have made it a popular choice for applications that require high-performance motor control..

Thank You.