Direct torque control of double star permanent magnet. The variable torque command is generated from the speed loop using a conventional pi controller which has been implemented in experimental work to validate the simulation results. A new technique for the torque control of induction motors was developed and presented by i. Pdf direct torque control of induction motor drives.
View direct torque control dtc research papers on academia. Direct torque control of brushless dc drives with reduced. Modeling and simulation of direct torque control induction. Direct torque control of permanent magnet synchronous motors. This control results in quick torque response in the transient operation and improvement in the steady state. This paper considers the application of direct torque control, to a. Design of direct torque controller of induction motor dtc. The control is quite different than the conventional fieldoriented or direct torque control. Torque control is one of important factors in drive train of electric vehicle.
Pdf direct torque control dtc is an emerging technique for controlling pwm inverterfed induction motor im drives. Drivetodrive link allows fast communication between. To understand the answer to this question we have to understand that the basic function of a variable speed drive vsd is to control the flow of energy from the mains to the process. Direct torque control dtc is one method used in variable frequency drives to control the torque and thus finally the speed of threephase ac electric motors. This control is characterized by good torque dynamic response, high robustness and less complexity than other controls 3. The direct torque control and field oriented control are nowadays.
Actuators must provide modulating damper control in response to a 2 to 10 vdc or, with the addition of a 500. Implementation and simulation of direct torque control. Direct torque control inverter drive systems abb avp. This voltage can damage the relay when actuating the brake. Control direct displacement control the ldu20 features direct displacement control ddc.
Delivering as minimum as possible ripple free torque with desired value to the wheels in various conditions, essentially increase safety and. It is proven by equations that the increase of electromagnetic torque is proportional to the increase of the. In this paper the direct torque control dtc which is one of the most excellent control strategies of ac motors which give very good steady and dynamic. It allows the precise and quick control of the im flux and torque without calling. Implement direct torque and flux controller dtfc or dtc. Improved direct torque control for sensorless matrix. Studies on direct torque controlbased speed control of.
Block diagram of the proposed drive system it relies on the principle that the torque and the magnitude of the stator flux are directly proportional with the ratio between the magnitude of the stator voltage and the stator frequency as given in 1 and 2 2. Jun 10, 20 this model simulates direct torque control of a three phase induction motor. Among the various control techniques available direct torque control dtc appears to be very convenient for ev propulsion. Control signala power feedbacka switches timing sec lmb243p5t 45 lbin. The choice of direct torque control from these methods gives advantages such as. Direct torque control or dtc is the most advanced ac drive technology developed by any manufacturer in the world this manuals purpose. Direct torque control of an induction motor file exchange. Direct torque controlled drive train for electric vehicle. Fieldoriented control uses spatial vector theory to optimally control magnetic field orientation. Although in these systems such variables as torque, flux modulus and flux sector are required, resulting dtc structure is particularly simplistic. This paper presents a comparative performance analysis of a new fivephase faulttolerant fluxswitching permanentmagnetftfspm motor for highreliability applications under the two most popular control schemes, namely, fieldoriented control foc and direct torque control dtc based on. Fieldoriented control and direct torque control for a. Control lever movement changes the speed and rotating direction of the motor by increasing or decreasing the swashplate angle.
It is proven by equations that the increase of electromagnetic torque is proportional to the increase of the angle between the stator flux and the rotor flux linkage. Firstly, the new motor topology and structural characteristics are. Direct torque control, permanent magnet synchronous motor, space vector modulation 1 introduction direct torque control was introduced by i. Many vfd manufacturers have flux capability like gozuk and abb. The efficiency of direct torque control for electric. Direct torque control for dual threephase induction motor drives. Flux control is the highest level and can match dc performance such as full torque at 0 speed. If this brake relay is a drycontact relay, electrical arcing can occur.
It is function of the frontal area shape protrusion such as side, mirrors, ducts and air passages spoilers and any other factor. Dtc has been successfully applied to induction machines 10, 11, and, more recently, to blac machines 12. Monographs in electrical and electronic engineering 25. Direct torque control technique for voltage source inverter. Oct 26, 2012 the main aim of direct torque control strategies is to effectively control the torque and flux of induction motor. The controllers for a direct torque control drive do not require complex coordinate transformation essential in all vector controlled drives. Vertical load and holding brake management application technique. Noguchi 1 as a new performant control strategy for induction motor drives fed by voltage source inverters vsi. Speed estimator is implemented to control of speed of motor along with the torque. Vf control, field oriented control, and direct torque control. Direct torque control concept direct torque control has its roots in fieldoriented control and direct self control. The direct torque control of induction machine is a simple control.
The measured input values to the dtc control are motor current and voltage. When the vsd operates in torque control mode, the speed is determined by the load. First, the produced torque is an explicitly continuous output variable of control. Using dtc it is possible to obtain a good dynamic control of torque without any mechanical transducers. Direct torque control dtc is the simplest method meant for torque control of a threephase induction motor. This study presents a control strategy for a double stator the permanent magnetsynchronous machine based on the direct control torque dtc using an pi regulator. View test prep sensorless vector and direct torque control ocr p. Reduction of torque ripples cause to deliver smoother power to the wheel. The sgmcs servomotor line is designed for direct drive applications where the load is directly attached to the motor surface. A new control technique of bldc was developed as direct torque control dtc. Pulse width modulated pwm drives rockwell automation. Direct torque control of a 6phase switched reluctance motor xu deng, prof. Direct torque control technique for voltage source inverter 631 controller imposes the time duration of the active voltage vectors, which move the stator flux along the reference trajectory, and the torque controller determinates the time duration of the zero voltage vectors which keep the motor torque in the predefined hysteresis tolerance band.
So a better dynamic answer in terms of torque is obtained. Shady gadoue electrical power research group school of electrical and electronic engineering newcastle university. Initially, dc motors were used as vsds because they could easily achieve the required speed and torque without the need for sophisticated electronics. The scheme is intuitive and easy to understand as a modular approach is followed. Direct torque control technique for voltage source. To maintain this simple control structure while at the same time improving the performance of the dtc drives two simple new techniques i. Ldu20 closed circuit axial piston transmission technical. Rc 350 rc 350 awd boasting direct and port fuel injection and an aweinspiring sound reminiscent of the lfa supercar, the 311horsepower 1 3. Space vector trajectory is also plotted to observe the performance. The fuzzy controller is designed to have three fuzzy state variables and one control variable for achieving direct torque control of the induction machine89, there are three variable input fuzzy logic controllers, the stator flux error, electromagnetic torque error, and. The torque and flux references are tracked using hysteresis controllers and a switching table implemented with lut is used for selecting the optimum converters output. Direct torque control of induction motor machines physics.
The plot above shows the steady state torque performance of a. Improvements in direct torque control of induction motor for wide. Due to their high torque and power per volume ratio, interior permanent magnet synchronous motors ipmsm are widespread electrical machines for traction drive. Advanced direct torque control of induction motor ieee xplore. Belimo model fail safe torque lbin control signal power feedback switches timing sec honeywell model torque lbin control signal power feedback switches timing sec tflb24 sr 22 lbin onoff 24 vacvdc 75 ms8103a1030 27 lbin twoposition spst.
Direct torque control principle direct torque control dtc is an optimised ac drives control principle where inverter switching directly controls the motor variables. Competitive cross reference direct coupled actuators belimo belimo model fail safe torque lbin control signal power feedback switches timing sec honeywell model torque lbin control signal power feedback switches timing sec cmb243 nsr 18 lbin onoff, floating 24 vacvdc 35 ml6161a2009 35 lbin onoff, floating 24 vac. So far, many techniques have been performed to reduce commutation torque ripple. Pdf design of direct torque controller of induction motor dtc. While dtc and vc have different concept of operation, they both provide an effective control of the flux and torque. Likewise, when operated in speed control, the torque is determined by the load. Pdf methods for direct torque control of induction machines. Low voltage ac drives abb industrial drives acs880. Direct torque control of permanent magnet synchronous.
Fieldoriented control and direct torque control for a five. Abbs version of flux control is direct torque control dtc. Direct torque control in ac drive technology what direct torque control dtc is, why and how it has evolved, the basic theory behind its success and the features and benefits of this new technology. Improved direct torque control strategy suitable for wide range speed control of induction motor drive. Vertical load and holding brake management application.
Direct the motor torque is proportional to the armature current. This paper presents a comparative performance analysis of a new fivephase faulttolerant fluxswitching permanentmagnetftfspm motor for highreliability applications under the two most popular control schemes, namely, fieldoriented controlfoc and direct torque controldtc based on statorflux orientation. Vertical load and holding brake management protect the brake relay against voltage that builds up on the relay terminals. Control signal power feedback switches timing sec honeywell actuator torque lbin. Direct torque control dtc is an emerging technique for controlling pwm inverterfed induction motor im drives. This direct drive motor has substantial load carrying bearings, low speed windings, and 1,048,576 ppr absolute encoders. This involves calculating an estimate of the motors magnetic flux and torque based on the measured voltage and current of the motor. In this paper, we presented the direct control of the torque of the synchronous double star machine supplied by two voltage inverters at two levels. Pdf direct torque control of induction motor drives researchgate. Delivering as minimum as possible ripple free torque with desired value to the wheels in various conditions, essentially increase safety and efficiency of electric vehicle. The principal of direct torque control using fuzzy logic fdtc.
Switching frequency varies according to the motor speed and the hysteresis bands of torque and flux, large torque ripple is generated in a low speed range. Field oriented control foc and direct torque control dtc. The converter consists of a single inverter stage, that uses gtos connected. The following figures present the block diagram of the controller for the two types of modulation. Direct torque control d tc is an improvised vc method. With the dtc scheme employing a voltage source inverter, it is possible to control directly the stator flux linkage and the electromagnetic torque by the optimum selection of inverter switching vectors.
It offers a simple control structure, fast response, and robust operation 35. Direct torque control method made the motor more accurate and fast torque control, high dynamic speed response and simple to control. The direct torque control dtc is the main interest of this project and it will be described in the following sections. This paper proposes an algorithm for direct flux and torque controlled three phase induction motor drive systems. Practitioners in the electric drives community have recently introduced a novel torque control strategy for high power induction motor applications. Competitive cross reference direct coupled actuators belimo cont. The fuzzy controller is designed to have three fuzzy state variables and one control variable for achieving direct torque control of the induction machine89, there are three variable input fuzzy logic controllers. The efficiency of direct torque control for electric vehicle. The direct torque controller dtc is built with two types of modulation, hysteresis modulation and space vector modulation svm. Direct torque control dtc for motor drive applications has been well established in both academia and industry. In dtfc, the motor torque and the flux are calculated from the primary variables, and they are controlled directly and independently by selecting optimum inverter switch modes 252. Assessment of direct torque control for induction motor drives. Direct torque control dtc is an advanced control technique with fast and dynamic torque response. Direct torque control of brushless dc motor using pi and.
Direct torque control and sensorless control of induction. The present study emphasizes speed control by using an external speed loop with dtc controller. Direct torque control dtc is a method used in variable frequency drives to control the torque and thus the speed of threephase ac electric motors. The performance index is calculated from operating speed, thd of stator current and switching. The modeling of an im drive employing dtc with application of. This paper describes an investigation of the direct torque control dtc for permanent magnet synchronous motor pmsm drive. The reference speed which is directly applied by the pedal of the vehicle is the input of the motor controller. The efficiency of direct torque control for electric vehicle behavior improvement 1 2. Direct torque control for induction motor drives main features of dtc decoupled control of torque and flux absence of mechanical transducers current regulator, pwm pulse generation, pi control of flux and torque and coordinate transformation are not required very simple control scheme and low computational time. In direct torque control instantaneous values of torque and flux are calculated from primary variables and controlled independently by using an optimum switching table. Variable speed drives vsds control information from abb the flow of energy from the mains to the process. Pdf high performance drives with induction machines require use of vector control.
Direct torque control of induction motor free download as powerpoint presentation. Modulating control damper actuators shall be electronic direct coupled type, which require no crank arm and linkage and be capable of direct mounting to a shaft up to 1. Direct torque control of doubly fed induction motor using threelevel. The swashplate angle is set directly by a control lever or linkage attached directly to the swashplate trunnion.
The speed control loop outputs the reference electromagnetic torque and stator flux of the machine. The main aim of direct torque control strategies is to effectively control the torque and flux of induction motor. This drive features closedloop speed control using hysteresisband torque and flux controllers. The dtc induction motor drive ac4 block represents an improved scalar control drive for induction motors with direct torque and flux control.
This paper considers the application of direct torque control, to a threephase bldc drive operating in the 120 conduc. The type of control employed for traction converter, direct self control controls the motor couple and speed. Pretapped mounting holes and a hollowthrough shaft permit a variety of machine designs. Studies on direct torque controlbased speed control of three. Direct torque control electrical engineering portal. A direct torque control dtc strategy for dual threephase induction motor drives is discussed in this paper.
The voltage is defined from the dcbus voltage and inverter switch positions. Competitive direct coupled actuator cross reference belimo. Improved direct torque control strategy suitable for wide range. The direct torque control is achieved by reference stator flux angle which is generates from. Implement direct torque and flux control dtc induction. Pdf modified direct torque control of threephase induction.
A simpler alternative to the vector control is the direct torque control dtc. Project report on direct torque control of permanent magnet synchronous motor as without his constant motivation and support during my work, this would not have been possible. Direct torque control of permanent magnet synchronous motor. It has been successfully applied to the design of flux vector controls and is well documented. In most of the papers the duty cycle control using fuzzy logic is applied for improvement of cdtc or implementation of cdtc with ai based switching controllers is. Direct torque control of a 6phase switched reluctance motor. Direct torque control of induction motor drive with flux. Mar, 2017 direct torque control dtc is an advanced control technique with fast and dynamic torque response. Optimised direct torque control of induction motor for.