This Paper gives a complete modeling and simulation of a twoinverterfedsixphase permanent magnet synchronous motor drive system, Then responsebasedcomparativeanalysis is done on starting torque ,settling time, Steady state current at various speed levels and torque levels by changing proportional-integral (PI) controller to Fuzzylogiccontroller. The PIcontroller has some disadvantages like, more settling time, sluggish response due to sudden change in load torque etc. So an intelligent controller, based on fuzzylogic is introduced which replaces the PI-controller and its drawbacks. The performance of both the controller has been investigated and studied by comparing the different plots obtained by setting various speed level both incremented and decremented speed, at different load conditions like No- load, fix load and dynamic load through Matlab / Simulink environment. Finally it is concluded from the result that fuzzylogicbasedcontroller is robust, reliable gives quick response with high starting torque and more effective than the conventional PIcontroller. It is also observed that both the proposed model can also run above rated speed significantally.
ABSTRACT: Brushless DC motors have gained popularity in electric drives applications such as industrial automotive equipments, instrumentations, aerospace etc due to its higher effciency, greater reliability, good dynamic response and very low maintenance. This paper presents speed control of four swich three phaseinverterfed BLDC with fuzzylogic implementation.Cost saving is achieved by reducing the number of components in the inverter circuit by implementing four switch topology.The sensorless techniques based on the back EMF difference estimation method is suggested.The design analysis and simulation of the proposed system is done using MATLAB/SIMULINK software.Also, simulation results of sensored driveusingPIcontroller and sensorless driveusingfuzzylogiccontroller are analyzed.
The control algorithm for the whole mitigation process is follows as to determine reference current for tracking actual current, to control dc link voltage, generate switching algorithm for IGBTs of voltage source inverter. FuzzylogicbasedPIcontroller gives the signal to reference current generator where with the help of PLL and small drive circuit reference current is generated. Reference current generation is based on pq theory. this generated reference current is then compared with the actual current in hysteresis band current controller where on behalf of error signal gate pulse is generated which is fed to the voltage source inverter . Voltage source inverter works according to gate pulse to injects current in same magnitude but opposite in phase to mitigate harmonic current of supply current.
Abstract— This paper presents a comparativeanalysis of speed control of brushless DC motor (BLDC) drivefed with conventional two-level, three and five level diode clamped resonant inverter (DC- MLI). The performance of the drive system is successfully evaluated usingFuzzyLogic (FL) based speed controller. The control structure of the proposed drive system is described. The speed and torque characteristic of conventional two-level inverter is compared with the three and five-level resonant inverter (MLI) for various operating conditions. The three and five level diode clamped resonant inverters are simulated using IGBT’s and the mathematical model of BLDC motor has been developed in MATLAB/SIMULINK environment. The simulation results show that the Fuzzybased speed controller eliminate torque ripples and provides fast speed response. The developed FuzzyLogic model has the ability to learn instantaneously and adapt its own controller parameters based on disturbances with minimum steady state error, overshoot and rise time of the output voltage.
Abstract: PMSM motor drives fed by dual inverter is purposely designed to reduced size and cost with respect to single motor drives fed by dual inverter. Previous researches on dual motor drives only focus on the modulation and the averaging techniques. Only a few of them, study the performance of the drives based on different speed controller other than Proportional and Integrator (PI) controller. This paper presents a detailed comparative study on fuzzy rule-base in FuzzyLogic speed Controller (FLC) for Dual Permanent Magnet Synchronous Motor (PMSM) drives. Twofuzzy speed controllers which are standard and simplified fuzzy speed controllers are designed and the results are compared and evaluated. The standard fuzzycontroller consists of 49 rules while the proposed controller consists of 9 rules determined by selecting the most dominant rules only. Both designs are compared for wide range of speed and the robustness of both controllers over load disturbance changes is tested to demonstrate the effectiveness of the simplified/reduced rule base. The developed FuzzyLogic model has the ability to learn instantaneously and adapt its own controller parameter based on disturbances with minimum steady state error, overshoot and rise time of the output voltage.
apart. Maximum torque is reached when the field lines are perpendicular. The commutation phase sequence is like AB-AC-BC-BACA-CB. Each conducting stage is called one step. Therefore, only two phases conduct current at any time, leaving the third phase floating. In order to produce maximum torque, the inverter should be commutated every 600 so that current is in phase with the back EMF. The commutation timing is determined by the rotor position, which can be detected by Hall sensors as shown in the Fig.1 (H1, H2, and H3). Current commutation is done by inverter as shown in a simplified from in Fig.2. The switches are shown as bipolar junction transistors but MOSFET switches are more common. Table 1 shows the switching sequence, the current direction and the position sensor signals.
decoupling or orthogonal control. DC machine like performance can also be extended to a PMSM if the machine control is considered in a rotating reference frame (rotating with rotor), where the sinusoidal variables appear as dc quantities in steady state. The Vector Control of PMSM consists of controlling the stator currents represented by a vector. This control is based on projections which transform a three phase time and speed dependent system into a two co- ordinate (d and q co-ordinates) time invariant system (using Park’s transformation). These projections lead to a structure similar to that of a DC machine control. Vector controlled machines need two constants as input references: the torque component current (aligned with the q co-ordinate) and the flux component current (aligned with d co-ordinate). The torque component current controls the torque and flux component current controls the flux of the machine independently. Therefore by using Vector control, independent control of the torque and flux producing currents are possible. This paper is
IT HAS been perceived for over two decades that portrayals of energy system loads for dynamic performance examination can have significant affect on control system soundness. As power systems are planned and worked with a lower soundness edge, sufficient load models are of major significance , . Regardless of colossal research endeavours and gained learning, stack demonstrating stays a standout amongst the most questionable ranges in huge scale control system reproductions due to the changing idea of burdens and the development of new sorts of burdens, for example, factor recurrence drives (VFDs).
Separately excited dc motor is coupled is load as shown in fig1 its field winding is energised by dc source and its armature is supplied by the controller when the dc voltage is applied on the armature current is produces in the armature conductor through the brushes and commutator since the rotor is also energies by dc voltage hence due to interaction of the armature back emf and field flux torque is produces and armature rotates. Under steady state condition the load torque T l opposes the electromagnetic torque T e .The proposed model is using the fully controlled
Nowadays energy need is mainly depends on conventional sources. But due to bounded availability of the sources, the analysis has shifted to renewable energy sources. In this wind energy is considered as the one of the best technologies. The wind energy conversion system (WECS) is now fulfilling the both grid-connected as well as stand-alone load demands. However, the wind flow was unpredictable, in order to maintain the continuous supply a suitable storage technique is required, for that a hybrid wind-battery system is considered for the desired load demand. In this paper a 4 KW hybrid wind and battery system is analyzed to meet the load demand of 3 KW stand-alone DC loads. On battery side the battery charger controller was designed based on the turbine maximum power point tracking and the state of charge of battery. From the mechanical side, the pitch control mechanism will look after the WECS. Both the control schemes are studied by using the FUZZY with PI environment at different wind profiles in MATLAB/SIMULINK.
The 3rd order and 5th order harmonics are said to be introduced into the system. The voltage sag, swell and harmonics are said to be mitigated in the distribution line using a DVR with conventional Proportional Integral (PI) controller and FuzzyLogic (FL) controller. The comprehensive results are presented to assess the performance of each controller as the best power quality solution. The simulations have been carried out using MATLAB/Simulink. The simulation diagram of a distribution power system with DVR is shown in figure-5.
In a conventional voltage source inverter, the two switches of any phase leg cannot be gated at the same time because this may cause a short circuit situation and thus destroy the inverter. In addition, the maximum output voltage cannot exceed the dc bus voltage. These limitations in such conventional voltage source inverter can be overcome by using ZSI . Actually, the ZSI is a power electronic converter with many advantages such as buck-boost characteristics, lower cost, and especially higher efficiency compared to traditional dc-dc converter , . As a more sophisticated design of ZSI, high-performance ZSI (HP-ZSI) copes with dc-link voltage drops for wide range of load with even using small inductor while guaranteeing a simple design. Thus, HP-ZSI is more suitable for HEV applications , .
This work proposes a multidimensional modulation (MDM) strategy based cascaded H- bridge multilevel inverter (CHBMLI). Various control techniques are employed in manipulating high energy output voltage from CHBMLI. Which is highly suitable for the variable speed drives that are naturally nonlinear in character. The proposed CHBMLI uses reduced number of switching devices that on the whole of the circuit operation minimizes the losses and hence improves the efficiency and performance. Multidimensional modulation control method accomplishes the output voltage in a controlled manner of improved THD. The performance of the MDM-CHBMLI is simulated in MATLAB/Simulink environment and the results are verified with the experimental implementation. The output of the MDM-CHBMLI assures its suitability on the PMSMdrive operation.
The control procedures that show a high torque powerful one can recognize the Direct Torque Control (DTC). DTC techniques have been generally executed in squirrel confine instigation machine drives. They permit an immediate control of the electromagnetic torque and the stator flux through the utilization of suitable mixes of the control signs of the inverter switches. Brushless DC (BLDC) motor control techniques, it is regularly trusted that they depend on the current and torque control approaches. A standout amongst the most well known is a summed up symphonious infusion to figure out ideal current waveforms minimizing the torque ripple. The DTC systems consider a vector determination table basically decreased to the torque control with a two-stage conduction mode amid divisions and a three-stage conduction mode amid area to-part substitutions. It manages the DTC of BLDC motors with a B4-inverter in the armature. It has been accounted for in that the two-stage conduction mode is punished by high torque ripple in the area to part substitutions. The present study builds up this methodology on account of B4-inverter-helps in BLDC motor drives under DTC. This segment manages the depiction and the operation premise of the B4-inverter-nourished BLDC motor drive. The drive's associations with two stages (stage A and stage B) of the BLDC motor supplied through the B4-inverter legs, while the third one (stage C) is connected to the center purpose of the dc-transport voltage. Managing Brushless DC (BLDC) motor control techniques. It is usually trusted that they depend on the current and torque control approaches. A standout amongst the most prevalent is a summed up symphonious infusion to discover ideal current waveforms minimizing the torque ripple.
Abstract- In this project Fuzzy base VSI fed PMBLDC motor drive is presented. The permanent magnet brushless DC motors (PMBLDCM) are now more popular in small and medium power applications due to its wide speed range operation, high efficiency, high starting torque, better reliability, low noise level, long lifetime, brush less construction, ease of control and reduced electromagnetic interference (EMI) problems. The PMBLDCM is controlled in the current controlled mode to achieve desired performance. The proposed improved power quality PMBLDCM drive is designed, modeled and simulated. The ac-dc conversion of electric power is usually required for BLDC motor drive; nevertheless, it causes many current harmonics and results in the poor power factor at input ac mains. This project deals with a ac- dc converter as a single-stage power factor correction (PFC) converter for a permanent magnet brushless dc Motor (PMBLDCM) fed through a Rectifier from a single-phase AC mains. The buck converter show conformity to international power quality standards with improved performance of PMBLDC Motor drive, such as reduction of AC main current harmonics, near unity power factor and reduction of speed and torque ripples. A Three-phase voltage source inverter is used as an electronic commutates to operate the PMBLDC Motor. This project presents an improved power quality bidirectional voltage source converter (VSC) fed permanent magnet brush less DC motor (PMBLDCM) drive by using MAT Lab/Simulink. Keywords- FuzzyLogicController, Bidirectional AC-DC converter, PMBLDCM drive, Power Quality (PQ), VSI.
Lyapunov theory based adaptive flux observer (AFO) for speed estimation: In the observer state equations rotor speed in speed sensor less drives are treated as un-known parameters. Estimation of states and un-known parameters are applied simultaneously using an adaptive technique. Lyapunov theory gives the adaptive technique equations where state estimation error is obtained by subtracting (1) from (2).
ABSTRACT:Application of power electronic based loads in industry has increased the importance and application of power quality studies. Power electronic equipment’s with nonlinear loads are broadly used in domestic, commercial and industrial applications causing for distortion in current and voltage waveforms. The electronic devices are very sensitive to disturbances and thus the industrial loads become less tolerant to power quality problems like voltage dips, voltage sags, voltage flickers, harmonics and load unbalance, real and reactive power problems etc. In addition to these, the other power quality problems have appeared in the system that reduces the overall efficiency of the system. In this paper, Unified Power Quality Conditioner (UPQC) has been modeled for both active and reactive power compensation usingPI and fuzzy control strategy. The behavior of UPQC has been analyzed and the system has been modeled using MATLAB and the results have been compared.
In industrial application, PIcontroller schemes are still the most commonly used due to their simplicity in design and stability in performance. Besides, They facing the limitations as (i) Controller design depends on the mathematical model of the system (ii) Expected performance not met due to the load changes (iii) It gives acceptable results at single set point (iv) The coefficients must be choose properly for acceptable results, besides that choosing of proper gains is very difficult for varying parameters like set point. Numerous methods such as fizzy-logic control have been proposed to replace PIcontroller schemes. However, unexpected change in load conditions or environmental factors would produce overshoot, oscillation of motor speed, oscillation of the torque, long settling time and thus causes deterioration of drive performance. To overcome this, an intelligent controllerbased on FuzzyLogic is proposed in the place of PI regulator.
Abstract: This paper proposes the use of Embedded Z –source inverter system with fuzzycontroller for adjustable speed drive applications. Closed loop operation with PI and FUZZY control strategies of EZSI system are proposed. EZSI produces the same voltage gain as Z-source inverter (ZSI) but due to the DC sources embedded within the X- shaped impedance network, it has the added advantage of inherent source filtering capability and also reduced capacitor sizing. This can be achieved without any extra passive filters. By controlling the shoot-through duty ratio and modulation index, EZSI system can produce any desired AC output voltage even greater than DC rail voltage and it also provides ride-through capability under voltage sag. These advantages are more significant for ASD to regulate the speed. The operational analysis and simulation results declared that EZSI is suitable for renewable energy applications to reduce the system complexity and thereby improving the efficiency of the inverter.
The regulation parts best suited for the MLI’s are referred from . Different utilizations for the MLI used for high power-uses were enrolled with the auto-voltage monitoring and controlling to a summed up MLI has been recommended by . The power based on MLI transformation framework is portrayed and a review on MLI has finished utilizing single DC source novel strategy for CMLH Bridge-Drive was explained in . A simplified technique based on diode clamped MLI is shown with a streamlined technique of DC- AC conversion based MLI, MLI based electrical uses and applications with a wide