Showing papers in "International Journal of Power Electronics in 2014"
TL;DR: In this article, an adaptive hysteresis current and voltage control technique for controlling Unified Power Quality Conditioner (UPQC) is proposed, which uses Artificial Neural Network (ANN) and Fuzzy Logic Controller (FLC) for generating the control pulses of the series and shunt APFs.
Abstract: An adaptive hysteresis current and voltage control technique for controlling Unified Power Quality Conditioner (UPQC) is proposed in this paper. The novelty of the proposed method is the series and shunt active power filters (APF) present in the UPQC has been controlled by the separate adaptive controllers for reducing the voltage and current perturbations. Here, the adaptive control technique utilises Artificial Neural Network (ANN) and Fuzzy Logic Controller (FLC) for generating the control pulses of the series and shunt APFs. In the adaptive control technique, ANN builds a target hysteresis control data based on the inputs such as voltage and current. By using the hysteresis control data, the control parameters are generated by the FLC. According to the output of FLC, PWM pulses are generated for controlling the APFs. The effectiveness of the proposed adaptive hysteresis control technique is identified by using the comparison analysis with the existing techniques.
17 citations
TL;DR: In this paper, a novel topology consisting of two interleaved stages and five voltage multiplier cells is presented, which is derived from a classical boost converter and utilises two switches, two inductors for the interleave stage, 12 diodes, 12 capacitors and one voltage lift capacitor to provide a voltage gain of 14.
Abstract: The output voltage available from renewable sources like photovoltaic panels, fuel cells and battery banks are too low to be practically utilised Therefore, the available voltage must be stepped up considerably before connecting to the load In this paper, a novel topology, which consists of two interleaved stages and five voltage multiplier cells, is presented The topology is derived from a classical boost converter and utilises two switches, two inductors for the interleave stage,12 diodes, 12 capacitors and one voltage lift capacitor to provide a voltage gain of 14 In general, a topology that provides a gain (N+ 2) times that of a classical boost converter utilises (2N+ 2) diodes and (2N+ 2) capacitors along with a voltage lift capacitor The primary feature of this topology is its capability to provide high-conversion ratio without using a transformer; additional features are, continuous input current, moderate duty cycle operation and modularity Experimental results obtained from a 100 W, 24 V/336 V prototype demonstrate the feasibility of the converter and validate the converter design
14 citations
TL;DR: In this paper, the authors presented mathematical analysis, design and simulation of a quadratic buck converter using fixed frequency Pulse-Width Modulation (PWM)-based Sliding-Mode (SM) controller in order to obtain fast dynamic performance.
Abstract: The switched-mode power supplies are widely used in very low voltage and high-power applications where large conversion ratios are required. In such cases, the quadratic buck converter is the suitable one compared to buck, cascaded buck and multi-phase choppers, because of their limitations in switching frequency and losses. This paper presents mathematical analysis, design and simulation of a quadratic buck converter using fixed frequency Pulse-Width Modulation (PWM)-based Sliding-Mode (SM) controller in order to obtain fast dynamic performance. The design aspects include choice of sliding surface, deriving existing and stability conditions, control parameter selection and their analysis. The performance of the proposed converter is compared with the conventional Average Current-Mode (ACM) controller. In average current mode, the tuning of the PI controller for the inner current loop and outer voltage loop is done using bode plots. The simulation results for the two types of controllers are represented for analysing dynamic performance, as well as line and load regulations.
14 citations
TL;DR: The performance of proposed three-level NPC rectifier-based midpoint converter-fed Switched Reluctance Motor drive is compared with a six-pulse bridge converter- fed SRM drive to demonstrate its improved power quality.
Abstract: This paper deals with a three-level Neutral Point Clamped (NPC) rectifier-based midpoint converter-fed Switched Reluctance Motor (SRM) drive. The three-level NPC rectifier for midpoint converter-fed SRM drive is used for improving power quality at AC mains and to balance the DC link capacitor voltages. The proposed three-level NPC rectifier is designed, modelled and its performance simulated using MATLAB/Simulink environment. The performance of proposed three-level NPC rectifier-based midpoint converter-fed SRM drive is compared with a six-pulse bridge converter-fed SRM drive to demonstrate its improved power quality.
9 citations
TL;DR: In this paper, a new topology of a cascaded multilevel inverter employing less number of switches with reduced gate driver circuits and simple control scheme is presented, and a comprehensive MATLAB/Simulink model of a seven-level inverter and the generation of control pulses using multi-carrier-based PWM is evolved and discussed.
Abstract: In the present scenario, the development of multilevel inverter is becoming popular for industrial applications and higher scale renewable green power technologies such as fuel cell, PV cell and wind turbine systems connected to the load. But the traditional multilevel topologies have large components and complex Pulse Width Modulation (PWM) controller leading to reduced harmonics and voltage stress on the load. Therefore, a new topology of a cascaded multilevel inverter employing less number of switches with reduced gate driver circuits and simple control scheme is presented in this paper. A comprehensive MATLAB/Simulink model of a seven-level inverter and the generation of control pulses using multi-carrier-based PWM is evolved and discussed. With the aid of LabVIEW, an experimental prototype is developed and their results are compared with simulation results.
9 citations
TL;DR: In this article, a novel causality bond graph model of hybrid models is suggested with the operation of the switch and the diode to be represented by a modulated transformer with a binary input and a resistor with fixed conductance causality.
Abstract: In this paper, bond graphs are employed to develop a novel mathematical model of conventional switched-mode DC-DC converters valid for both continuous and discontinuous conduction modes. A unique causality bond graph model of hybrid models is suggested with the operation of the switch and the diode to be represented by a modulated transformer with a binary input and a resistor with fixed conductance causality. The operation of the diode is controlled using an if-then function within the model. The extracted hybrid model is implemented on a boost and buck converter with their operations to change from CCM to DCM and to return to CCM. The vector fields of the models show validity in a wide operational area and comparison with the simulation of the converters using PSPICE reveals high accuracy of the proposed model, with the normalised root means square error and the maximum absolute error remaining adequately low. The model is also experimentally tested on a buck topology.
7 citations
TL;DR: In this article, the authors tried to figure out basic differences between PI control and SMC concepts in shaping up a completely engineered product in power electronics domain, using experimental design approach.
Abstract: Power electronics equipment is deployed for control of power flow in electrical domain. Steady and fast growth in controller, active and passive power and control components, power control topologies etc. and the impact on overall gains it makes to society have led the evolution process of power electronics field to mature fast. Apparently, contemporary SMC concepts with their simple implementation procedures using structure switching mechanism along with their ability to reject disturbances and also generate parametric insensitivity remain very attractive research area for several decades. However, compared to PI control, their market penetration in power electronics domain is below expected line. Inertia to market penetration of SMC idea is large. For practical implementation, PI control remains as industry standard. This paper, using experimental design approach, tries to figure out basic differences between PI control and SMC concepts in shaping up a completely engineered product in power electronics domain.
6 citations
TL;DR: In this article, the authors present mathematical analysis, design and simulation of a quadratic buck converter used as LED lamp driver, and the performance of the converter is compared with two different control strategies.
Abstract: This paper presents mathematical analysis, design and simulation of a quadratic buck converter used as LED lamp driver, and the performance of the converter is compared with two different control strategies. The objective is to provide tight regulation of the LED current that can operate over a wide range of DC input voltages. The first control strategy is the non–linear Sliding–Mode (SM) current controller, and its design aspects include choice of sliding surface, deriving existing and stability conditions, control parameter selection and their analysis. This paper also throws light on Average Current–Mode (ACM) controller. The operation, modelling, designing and transfer function derivation for the inner current and outer voltage loops of the quadratic buck converter are presented. The tuning of controllers for the ACM controller is done using Bode plots, for achieving desired phase and gain margins. The simulation is done using PSIM software and the results are presented.
5 citations
TL;DR: In this paper, two approaches are proposed to improve the output voltage waveform of a single phase PWM inverter, one based on selected harmonic elimination (SHE) of order up to 7th harmonic, and the other based on ripple current minimization using LMA.
Abstract: This paper is aimed at improving the output voltage waveform of a single phase PWM inverter. Two approaches is proposed, the first approach is based on selected harmonic elimination (SHE) of order up to 7th harmonic, for minimising harmonic distortion and modulating amplitude of the fundamental component of the output voltage waveform. For the first time, the Levenberg– Marquardt algorithm (LMA) is used for determining the switching angles of the inverter switches. The second approach is based on ripple current minimisation using LMA. A simulation model is developed using PSIM for the inverter to verify the proposed approaches. An experimental system was implemented to demonstrate the effectiveness of the proposed approaches by using PIC16F877 microcontroller. Analysis of the voltage THD as influenced by the amplitude modulation index is made using MATLAB based on the computed switching angles.
4 citations
TL;DR: The paper discusses the problem of speed and flux estimation for the induction motor (IM) drive and presents a series of Sliding Mode Observers (SMOs) that are constructed using compound manifolds that have unique and useful properties.
Abstract: The paper discusses the problem of speed and flux estimation for the induction motor (IM) drive and presents a series of Sliding Mode Observers (SMOs) that are constructed using compound manifolds. Observers with compound manifolds have not been widely investigated because they cannot be designed following a standard procedure; however, it is shown that they have unique and useful properties. The paper introduces the candidate manifolds associated with IM estimation and shows various approaches for designing SMOs with compound manifolds. Generally, using the IM model, it is typical to design observers with simple manifolds. However, since the state transition matrix of the IM model depends on the motor speed, the problem is more complicated – the speed must either be known or it must be estimated. In the paper, several sensored and sensorless observer designs are presented. The paper presents the theoretical developments and shows simulations and experimental results.
3 citations
TL;DR: In this paper, a STATCOM-based voltage and frequency regulation for stand-alone asynchronous generator feeding linear and nonlinear loads is presented, where a DC chopper with dump load is connected across DC bus capacitor to regulate varying consumer load.
Abstract: This paper presents a STATCOM-based voltage and frequency regulation for stand-alone asynchronous generator feeding linear and nonlinear loads. The SEIG have inherent poor voltage and frequency regulation. The voltage and frequency depend upon the load current and power factor of the load with fixed excitation capacitor employing unregulated turbines. The changing consumer load requires variable reactive power compensation for excitation requirement. Consumer load contains harmonics and performance of SEIG is largely affected by these load harmonics. A current controlled voltage source inverter working as STATCOM is used for harmonic elimination, load balancing and variable reactive power compensation. A DC chopper with dump load is connected across DC bus capacitor to regulate varying consumer load. The control algorithm has been first co-simulated with processor in the loop (PIL) and then experimentally validated. The transient behaviour of developed prototype system for application and removal of balanced, unbalanced, nonlinear load is investigated.
TL;DR: In this article, the speed and rotor position estimation for the Permanent Magnet Synchronous Motor (PMSM) is discussed and a family of estimation methods is presented, based on the model of the PMSM in the stationary reference frame.
Abstract: The paper discusses the problem of speed and rotor position estimation for the Permanent Magnet Synchronous Motor (PMSM) and presents a family of estimation methods. Estimation is done sequentially: first, the EMFs are obtained using a sliding mode observer; then, the speed is estimated. The estimators are based on the model of the PMSM in the stationary reference frame. The paper presents an SM observer for the EMFs (the front observer) and various observers for the speed (the back observers). It is shown that the speed estimation process offers many mathematical options - it can be adaptive, sliding–mode based, algebraic, or it can use a double–manifold sliding mode structure. The properties of the various speed observers and their feasibility and accuracy are discussed. The method can be applied in a sensorless PMSM drive where the speed and rotor position angle are needed for control implementation. The paper presents the design of the observers along with simulation results and experimental tests.
TL;DR: In this article, the authors compared the performance of sliding-mode speed controller and fuzzy logic speed controller in a MATALB/Simulink environment at different operating conditions, such as forward and reversal motoring with no load, load, sudden change in speed and sudden zero speed.
Abstract: In this research study, direct torque and flux control of an Induction Motor Drive (IMD) using Sliding-Mode Speed Controllers (SMSC) and Fuzzy-Logic Speed Controller (FLSC) are presented to achieve high performance of stator current, electromagnetic torque and motor speed in both transient as well as in steady-state conditions. The PI Speed Controller (PISC) gives good steady-state performance, but poor dynamic response. Therefore, the SMSC is considered to achieve continuous control of motor speed and also electromagnetic torque. Furthermore, FLSC is considered to get high performance, dynamic tracking and speed accuracy at various load torque conditions. The performances of each speed controller techniques are tested under various load toque and speed condition for its robustness. A detailed comparison of different control approaches are carried out in a MATALB/Simulink environment at different operating conditions, such as forward and reversal motoring with no-load, load, sudden change in speed and sudden zero speed.
TL;DR: In this article, a non-linear inductance profile estimation of a Switched Reluctance Machine (SRM) using real-time applicable modelling techniques is presented. The estimation techniques are based on regression analysis and Adaptive Neuro-Fuzzy Inference System (ANFIS).
Abstract: This paper presents a non-linear inductance profile estimation of a Switched Reluctance Machine (SRM) using real-time applicable modelling techniques. The estimation techniques are based on regression analysis and Adaptive Neuro-Fuzzy Inference System (ANFIS). Mathematical models of phase inductance L(I,θ) using both the techniques have been successfully tested for various values of phase currents (Iph) and rotor positions (θ) of a non-linear SRM. It is observed that the proposed techniques are highly suitable for inductance L(I,θ) modelling of SRM, which is found to be in good agreement with the training data used for modelling.
TL;DR: The performance of the proposed BLDC motor drive is evaluated for wide range of speed control with power quality indices with-in the recommended limits of international power quality standards such as IEC 61000-3-2.
Abstract: This paper presents a single-stage isolated power factor corrected power supply (SSIPP) fed permanent magnet brushless DC (BLDC) motor drive. An advantage of fast voltage regulation with single voltage control loop of SSIPP is utilised to develop a power factor correction (PFC) based BLDC motor drive. The speed of BLDC motor is controlled by varying the DC link voltage of the voltage source inverter (VSI) feeding BLDC motor using a single voltage sensor. A boost-flyback SSIPP operating in discontinuous inductor current mode (DICM) is used for the voltage control with improved power quality at AC mains. A fundamental frequency switching of VSI is used instead of pulse width modulation (PWM) switching to avoid high frequency switching losses in it. The performance of the proposed BLDC motor drive is evaluated for wide range of speed control with power quality indices with-in the recommended limits of international power quality standards such as IEC 61000-3-2.
TL;DR: In this paper, a scaleddown 1 kW BDC prototype is built to verify the feasibility of the efficiency improvement, with the aim of achieving ZVS conditions and variable frequency control, the implementing method is proposed.
Abstract: Hybrid energy storage system (HESS) can be adopted in hybrid, plug-in hybrid, and pure electric vehicles (HEV, PHEV, and EV), where a bidirectional DC-DC converter (BDC) is used to connect batteries and ultracapacitors. The efficiency improvement of the BDC is beneficial to increase the efficiency viability of HESS. Due to ZVS, high efficiency can be obtained at heavy load operations while the efficiency is low at light load operations mainly because of the conduction losses of the auxiliary circuits. These losses can be reduced by optimising the switching frequency. The relationship of efficiency and switching frequency are presented and discussed. A scaleddown 1 kW BDC prototype is built to verify the feasibility of the efficiency improvement. With the aim of achieving ZVS conditions and variable frequency control, the implementing method is proposed. The simulated results are also presented, which can validate the feasibility of the proposed control method.
TL;DR: In this article, the authors proposed a brushless DC motor drive system based on the 3G technology, which allows sending a text message with the control command from a remote area to the desired location.
Abstract: Instant messaging among mobile phone allows rapid transmission of short messages that permit any person to share ideas, opinions and other appropriate information. In this paper, the proposed control system is based on the 3G technology, which allows sending a text message with the control command from a remote area to the desired location. The mathematical model and the design PID speed controller for the brushless DC motor drive system are presented. A Hybrid Bacterial Foraging Particle Swarm Optimisation (HBF–PSO) algorithm is employed in order to obtain the controller parameters assuring enhanced step response performance criterion. Simulation results of the designed controllers are compared with that of classical evolutionary algorithm controllers whose parameters are adjusted using Practical Swarm Optimisation (PSO) and Bacterial Foraging Optimisation (BFO). Experimental and simulations results signify the superiority of the proposed technique over the PSO and BFO methods and allow the proposed system a greater degree of freedom to control and monitor the electric drive system.
TL;DR: In this article, a design method for a new practical LCL filter based on SAPF is proposed in order to compensate for existing source-type current harmonics, which is difficult because harmonic current has a large variation and the current loop has a steady-state error.
Abstract: Shunt Active Power Filter (SAPF) can be applied to compensate for existing source-type current harmonics. However, high-precision compensation is difficult because harmonic current has a large variation and the current loop has a steady-state error. A design method for a new practical LCL filter based on SAPF is proposed in this paper. A harmonic model of the LCL filter is built based on SAPF application. The changing relationship between the parameters of the filter and harmonic frequency is then examined. The suitable values for the parameters are determined based on the precondition of having a split ratio of 1, the limit scope of LCL resonance frequency and the ratio of the capacitance branch’s impedance parameter in combination with the relationship curve of the inductance parameter ratio and harmonic frequency as well as the respective requirements of the LCL regarding the attenuating properties of lowand high-frequency bands. Finally, the validity and feasibility of the design method are verified by conducting an experiment with SAPF’s industrial prototype.
TL;DR: A practical design for a DC/DC buck converter was considered in this study, which results in a more comprehensive understanding for the phenomenon, and showed that if the system has a well–designed buck converter as well as a feedback controller, then it does not exhibit any nonlinear behaviour.
Abstract: In this paper, the nonlinear phenomenon in DC/DC buck converter is studied. A practical design for a DC/DC buck converter was considered in this study, which results in a more comprehensive understanding for the phenomenon. The nonlinearity of the buck converter is studied using the iteration mapping technique. The results showed that if the system has a well–designed buck converter as well as a feedback controller, then it does not exhibit any nonlinear behaviour. To verify these results, a buck converter, with non–practical parameters, was also studied. In this case, the results showed bifurcation and then chaotic behaviour for the output voltage and inductor current as the input voltage changes. A comparison between the two cases is discussed in more details.