Zeitschriften und Ausgaben

Volumen 18 (2022): Heft 1 (June 2022)

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Volumen 15 (2019): Heft 2 (December 2019)

Volumen 15 (2019): Heft 1 (September 2019)

Volumen 14 (2018): Heft 2 (December 2018)

Volumen 14 (2018): Heft 1 (July 2018)

Volumen 13 (2017): Heft 1 (December 2017)

Volumen 12 (2017): Heft 1 (July 2017)

Volumen 11 (2016): Heft 1 (December 2016)

Volumen 10 (2016): Heft 1 (July 2016)

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Zeitschriftendaten
Format
Zeitschrift
eISSN
2255-9159
Erstveröffentlichung
31 Jan 2013
Erscheinungsweise
2 Hefte pro Jahr
Sprachen
Englisch

Suche

Volumen 14 (2018): Heft 1 (July 2018)

Zeitschriftendaten
Format
Zeitschrift
eISSN
2255-9159
Erstveröffentlichung
31 Jan 2013
Erscheinungsweise
2 Hefte pro Jahr
Sprachen
Englisch

Suche

10 Artikel
Open Access

Asymmetric snubberless current-fed full-bridge isolated DC-DC converters

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 5 - 11

Zusammenfassung

Abstract

This paper presents two isolated current-fed fullbridge DC-DC converters that can be used to interface a lower voltage source into a DC bus of higher voltage. The first topology uses a resonant circuit to force current redistribution between low-voltage-side transistors and a passive rectifier. The second topology utilizes an active rectifier with secondary modulation to achieve the same goal. The resonant circuit can be formed by using transformer leakage inductance and the parasitic capacitances of the switches. The converters feature soft switching of semiconductors over a wide range of operating conditions. This is achieved with decreased energy circulation when compared to existing topologies with symmetric control and with fewer semiconductors than in those with phase-shift control. The topologies can be implemented in renewable, supercapacitor, battery, fuel cell, and DC microgrid applications. Steady-state operation and design aspects of the converters are presented and verified experimentally with 400 W prototypes

Schlüsselwörter

  • DC-DC power converters
  • soft switching
  • zerocurrent switching
  • zero-voltage switching
Open Access

A novel hysteresis power point optimizer for distributed solar power generation

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 12 - 22

Zusammenfassung

Abstract

This paper proposes a new photovoltaic panel maximum-power-point optimizer based on a buck converter. It can be connected to the DC-link distributed energy harvesting system that should perform the true maximum-power-point tracking algorithm based on maintaining a constant DC link voltage. The algorithm is based on the sensorless hysteresis control and ensures high efficiency. Three different realizations of proposed hysteresis optimizers have been analyzed in the paper, including operation principle and adjustment of hysteresis intervals. An experimental study has been performed for a portable low-power photovoltaic system in case of different loads and irradiance levels. The efficiency of maximum power point tracking has been calculated analytically for different hysteresis intervals and validated by experiment, which proved a 97-98 % efficiency of tracking for different PV panel temperatures. The proposed solution is recommended to be used in small- and medium-sized power systems where the price of the conventional maximum power point tracking converter is very high and is comparable to the cost of the individual panel

Schlüsselwörter

  • DC-DC power converters
  • maximum power point tracker
  • photovoltaic systems
  • renewable energy sources
Open Access

Data rate profiles of coded/uncoded power line channel with single-carrier/multicarrier modulation techniques

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 23 - 29

Zusammenfassung

Abstract

The power-line communication (PLC) technique involves sending information through an electrical conductor for a commercial or domestic purpose. Lately, electronic means of communication have gained popularity for the transfer of information. Conversely, there is an increased requirement for more transmission media, like the use of power line as a communication channel for remote data delivery. This paper focuses on determining the data rate profile achievable using the single-carrier/multicarrier modulation techniques with Reed- Solomon concatenated convolutional (RS-CC) codes for data transmission through a power line channel. In this investigation, MATLAB/SIMULINK was used to explore a low-voltage power line as a communication channel for high data transmission rate. Data transmission was accomplished by utilizing a parametric model of a power line channel with the different kinds of noise considered in the simulation. In the designed power-line communication (PLC) system, single-carrier modulation offered a maximum of 14.4 Mbps reduction in the data rate when the uncoded 64-quadrature amplitude modulation (QAM) was compared to coded 64-QAM with 1/2 forward error correction (FEC). In the OFDM power-line communication (PLC) system, the decrease in the data rate was maximal at 39 Mbps when the uncoded 16-QAM was contrasted with the 16-QAM having 1/2 FEC. It was evident that the increased code rate of the PLC system using single-carrier and OFDM modulation implied increased data rate profiles

Schlüsselwörter

  • channel
  • data rate
  • forward error correction (FEC)
  • multicarrier
  • power line
  • Reed-Solomon concatenated convolutional code
  • single-carrier
Open Access

An efficient radio frequency channel distribution in 5g heterogeneous cellular networks for avoiding cross-tier interference in macro and small cells

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 30 - 38

Zusammenfassung

Abstract

Recently, the need for user data rate traffic has increased for running high-bandwidth applications. Therefore, the way forward lies in 5G heterogeneous cellular networks. The 5G network is comprised of two network hierarchies. As the first hierarchy, there are MBSs with large macro cells for macro users. As the second hierarchy, there are FBSs referred to as small cells for femto users. The 5G networks encourage the use of large macro and small cells for efficient utilisation and distribution of channel resources. In this study, the authors have proposed an efficient RF channel distribution mechanism on the basis of the current SINR levels of FUEs and MUEs. On the basis of the users’ present SINR levels, the channels will be allocated by the central MBS to MUEs and FUEs via FBSs. The major obstacle in RF channel allocation to FUEs and MUEs is cross-tier interference at the downlink channel at the MUEs and FUEs from the transmitted signals of MBSs and FBSs. In this study, an efficient RF channel allocation scheme is proposed on the basis of channel modelling constraints, which will minimise the cross-tier interference at the downlink channel at the MUEs and FUEs during RF channel allocation to FUEs and MUEs present in the same coverage area

Schlüsselwörter

  • 5G heterogeneous cellular networks
  • centralised MBS
  • Femto base station (FBS)
  • Femto user equipment (FUE)
  • macro base station (MBS)
  • macro cell
  • radio frequency (RF)
  • macro user equipment (MUE)
  • received signal strength indication (RSSI)
  • signal-to-interference-plus-noise ratio (SINR)
  • small cell
Open Access

Inverse methods and integral-differential model demonstration for optimal mechanical operation of power plants – numerical graphical optimization for second generation of tribology models

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 39 - 50

Zusammenfassung

Abstract

Stepping forward from a previous conference contribution, the article focuses on extension of inverse problem algorithms to integral-differential modelling and formal/strict demonstration of graphical-optimization method. It shows evident-mathematical and 3D-imaging proofs of the graphical optimization method with L1 Norm simulations and algorithms. At present, Linear/Nonlinear Optimization mathematical methods constitute the choice of preference in getting improvements for erosion and corrosion simulations- determinations in general tribology, biotribology and tribocorrosion. The method(s) developed are classical numerical optimization settings for objective functions, programming optimization and simulations, and special software for imaging in 3D. Results are diverse and the range of their applications is wide. First, the article provides a definite formal demonstration of the nonlinear graphical optimization both in numerical results and in imaging. Then, the authors propose the development of programming optimization and mathematical proofs-algorithms of the integral-differential model for various models. Subsequently, an overview of stochastic erosion methods based on Markov Chain is presented in the article. Finally, the second generation of tribology models is defined and conceptually explained. To summarise, the article comprises new findings towards modernization of tribology, biotribology and tribocorrosion models, gathering innovative research branches for future extension of the mathematical modelling progress. The results can be applied to both general techniques and mechanical engineering. The analytical and numerical demonstration of the integral-differential model constitutes a key point and essential result of the research. Extension to electromagnetic and electronic models of these methods is also considered feasible and practical

Schlüsselwörter

  • engineering reliability operational probabilities
  • functional power plants
  • inverse problem theory/applications
  • nonlinear optimization
  • power engineering
Open Access

An attempt of finding an appropriate number of convolutional layers in cnns based on benchmarks of heterogeneous datasets

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 51 - 57

Zusammenfassung

Abstract

An attempt of finding an appropriate number of convolutional layers in convolutional neural networks is made. The benchmark datasets are CIFAR-10, NORB and EEACL26, whose diversity and heterogeneousness must serve for a general applicability of a rule presumed to yield that number. The rule is drawn from the best performances of convolutional neural networks built with 2 to 12 convolutional layers. It is not an exact best number of convolutional layers but the result of a short process of trying a few versions of such numbers. For small images (like those in CIFAR-10), the initial number is 4. For datasets that have a few tens of image categories and more, initially setting five to eight convolutional layers is recommended depending on the complexity of the dataset. The fuzziness in the rule is not removable because of the required diversity and heterogeneousness

Schlüsselwörter

  • convolutional neural networks
  • convolutional layers
  • error rate
  • hyperparameters
  • performance
Open Access

Adaptive quadrilateral distance relaying scheme for fault impedance compensation

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 58 - 70

Zusammenfassung

Abstract

Impedance reach of numerical distance relay is severely affected by Fault Resistance (RF), Fault Inception Angle (FIA), Fault Type (FT), Fault Location (FL), Power Flow Angle (PFA) and series compensation in transmission line. This paper presents a novel standalone adaptive distance protection algorithm for detection, classification and location of fault in presence of variable fault resistance. It is based on adaptive slope tracking method to detect and classify the fault in combination with modified Fourier filter algorithm for locating the fault. To realize the effectiveness of the proposed technique, simulations are performed in PSCAD using multiple run facility & validation is carried out in MATLAB® considering wide variation in power system disturbances. Due to adaptive setting of quadrilateral characteristics in accordance with variation in fault impedance, the proposed technique is 100 % accurate for detection & classification of faults with error in fault location estimation to be within 1 %. Moreover, the proposed technique provides significant improvement in response time and estimation of fault location as compared to existing distance relaying algorithms, which are the key attributes of multi-functional numerical relay

Schlüsselwörter

  • computer numerical control
  • discrete Fourier transforms
  • electrical fault detection
  • phasor measurement
  • power system faults
  • power system protection
Open Access

Considerations regarding the concept of cost-effective power-assist wheelchair subsystems

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 71 - 80

Zusammenfassung

Abstract

The present paper deals with the concept of a cost-effective power-assistant wheelchair. An analysis of the market situation and recent technical achievements is done at the beginning. On its basis, a set of solutions suitable for the development of such wheelchairs has been composed. It is shown that the key features of the considered concept are: segmented electrical motor and drive, sectioned battery pack, modular charger and an ANN matrix that provides easy and intuitive interfacing of sensor networks, pseudo-bionic feedbacks and the decision-making unit. Within the scope of the paper, a 3D model has been developed and 3D modelling has been conducted. As a result, certain drawbacks in the design and placement of elements have been found and a modification of the concept has been proposed

Schlüsselwörter

  • artificial neural networks
  • batteries
  • electrical drives
  • human-machine interface
  • medical control systems
Open Access

Development case study of the first estonian self-driving car, iseauto

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 81 - 88

Zusammenfassung

Abstract

The rapid development of intelligent control technology has also brought about changes in the automotive industry and led to development of autonomous or self-driving vehicles. To overcome traffic and environment issues, self-driving cars use a number of sensors for vision as well as a navigation system and actuators to control mechanical systems and computers to process the data. All these points make a self-driving car an interdisciplinary project that requires contribution from different fields. In our particular case, four different university departments and two companies are directly involved in the self-driving car project. The main aim of the paper is to discuss the challenges faced in the development of the first Estonian self-driving car. The project implementation time was 20 months and the project included four work packages: preliminary study, software development, body assembly and system tuning/testing of the self-driving car. This paper describes the development process stages and tasks that were distributed between the sub-teams. Moreover, the paper presents the technical and software solutions that were used to achieve the goal and presents a self-driving last mile bus called ISEAUTO. Special attention is paid to the discussion of safety challenges that a self-driving electrical car project can encounter. The main outcomes and future research possibilities are outlined

Schlüsselwörter

  • automotive engineering
  • autonomous vehicles
  • vehicle driving
  • vehicle safety
Open Access

Simulation study of mixed pressure and flow control systems for optimal operation of centrifugal pumping plants

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 89 - 94

Zusammenfassung

Abstract

A Simulink/DriveSize based model for the mutual pressure and flow control of a centrifugal pumping plant with a variable speed drive is proposed. The model provides the possibility of power calculation during both throttling and speed control and to estimate the optimal working point according to these calculations. The model is developed to provide the possibility of power reduction during pressure and flow maintenance with the help of mixed pressure control strategy. To evaluate the system, a series of experiments have been conducted. After the validation of the proposed model through testing, which proved that the designed system is more beneficial from the power consumption point of view than the traditional pressure control methods, it can be stated that the system is useful for pressure and flow control optimization of the centrifugal pumping plants

Schlüsselwörter

  • centrifugal pump
  • MATLAB
  • modelling
  • power measurement
  • variable speed drive
10 Artikel
Open Access

Asymmetric snubberless current-fed full-bridge isolated DC-DC converters

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 5 - 11

Zusammenfassung

Abstract

This paper presents two isolated current-fed fullbridge DC-DC converters that can be used to interface a lower voltage source into a DC bus of higher voltage. The first topology uses a resonant circuit to force current redistribution between low-voltage-side transistors and a passive rectifier. The second topology utilizes an active rectifier with secondary modulation to achieve the same goal. The resonant circuit can be formed by using transformer leakage inductance and the parasitic capacitances of the switches. The converters feature soft switching of semiconductors over a wide range of operating conditions. This is achieved with decreased energy circulation when compared to existing topologies with symmetric control and with fewer semiconductors than in those with phase-shift control. The topologies can be implemented in renewable, supercapacitor, battery, fuel cell, and DC microgrid applications. Steady-state operation and design aspects of the converters are presented and verified experimentally with 400 W prototypes

Schlüsselwörter

  • DC-DC power converters
  • soft switching
  • zerocurrent switching
  • zero-voltage switching
Open Access

A novel hysteresis power point optimizer for distributed solar power generation

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 12 - 22

Zusammenfassung

Abstract

This paper proposes a new photovoltaic panel maximum-power-point optimizer based on a buck converter. It can be connected to the DC-link distributed energy harvesting system that should perform the true maximum-power-point tracking algorithm based on maintaining a constant DC link voltage. The algorithm is based on the sensorless hysteresis control and ensures high efficiency. Three different realizations of proposed hysteresis optimizers have been analyzed in the paper, including operation principle and adjustment of hysteresis intervals. An experimental study has been performed for a portable low-power photovoltaic system in case of different loads and irradiance levels. The efficiency of maximum power point tracking has been calculated analytically for different hysteresis intervals and validated by experiment, which proved a 97-98 % efficiency of tracking for different PV panel temperatures. The proposed solution is recommended to be used in small- and medium-sized power systems where the price of the conventional maximum power point tracking converter is very high and is comparable to the cost of the individual panel

Schlüsselwörter

  • DC-DC power converters
  • maximum power point tracker
  • photovoltaic systems
  • renewable energy sources
Open Access

Data rate profiles of coded/uncoded power line channel with single-carrier/multicarrier modulation techniques

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 23 - 29

Zusammenfassung

Abstract

The power-line communication (PLC) technique involves sending information through an electrical conductor for a commercial or domestic purpose. Lately, electronic means of communication have gained popularity for the transfer of information. Conversely, there is an increased requirement for more transmission media, like the use of power line as a communication channel for remote data delivery. This paper focuses on determining the data rate profile achievable using the single-carrier/multicarrier modulation techniques with Reed- Solomon concatenated convolutional (RS-CC) codes for data transmission through a power line channel. In this investigation, MATLAB/SIMULINK was used to explore a low-voltage power line as a communication channel for high data transmission rate. Data transmission was accomplished by utilizing a parametric model of a power line channel with the different kinds of noise considered in the simulation. In the designed power-line communication (PLC) system, single-carrier modulation offered a maximum of 14.4 Mbps reduction in the data rate when the uncoded 64-quadrature amplitude modulation (QAM) was compared to coded 64-QAM with 1/2 forward error correction (FEC). In the OFDM power-line communication (PLC) system, the decrease in the data rate was maximal at 39 Mbps when the uncoded 16-QAM was contrasted with the 16-QAM having 1/2 FEC. It was evident that the increased code rate of the PLC system using single-carrier and OFDM modulation implied increased data rate profiles

Schlüsselwörter

  • channel
  • data rate
  • forward error correction (FEC)
  • multicarrier
  • power line
  • Reed-Solomon concatenated convolutional code
  • single-carrier
Open Access

An efficient radio frequency channel distribution in 5g heterogeneous cellular networks for avoiding cross-tier interference in macro and small cells

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 30 - 38

Zusammenfassung

Abstract

Recently, the need for user data rate traffic has increased for running high-bandwidth applications. Therefore, the way forward lies in 5G heterogeneous cellular networks. The 5G network is comprised of two network hierarchies. As the first hierarchy, there are MBSs with large macro cells for macro users. As the second hierarchy, there are FBSs referred to as small cells for femto users. The 5G networks encourage the use of large macro and small cells for efficient utilisation and distribution of channel resources. In this study, the authors have proposed an efficient RF channel distribution mechanism on the basis of the current SINR levels of FUEs and MUEs. On the basis of the users’ present SINR levels, the channels will be allocated by the central MBS to MUEs and FUEs via FBSs. The major obstacle in RF channel allocation to FUEs and MUEs is cross-tier interference at the downlink channel at the MUEs and FUEs from the transmitted signals of MBSs and FBSs. In this study, an efficient RF channel allocation scheme is proposed on the basis of channel modelling constraints, which will minimise the cross-tier interference at the downlink channel at the MUEs and FUEs during RF channel allocation to FUEs and MUEs present in the same coverage area

Schlüsselwörter

  • 5G heterogeneous cellular networks
  • centralised MBS
  • Femto base station (FBS)
  • Femto user equipment (FUE)
  • macro base station (MBS)
  • macro cell
  • radio frequency (RF)
  • macro user equipment (MUE)
  • received signal strength indication (RSSI)
  • signal-to-interference-plus-noise ratio (SINR)
  • small cell
Open Access

Inverse methods and integral-differential model demonstration for optimal mechanical operation of power plants – numerical graphical optimization for second generation of tribology models

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 39 - 50

Zusammenfassung

Abstract

Stepping forward from a previous conference contribution, the article focuses on extension of inverse problem algorithms to integral-differential modelling and formal/strict demonstration of graphical-optimization method. It shows evident-mathematical and 3D-imaging proofs of the graphical optimization method with L1 Norm simulations and algorithms. At present, Linear/Nonlinear Optimization mathematical methods constitute the choice of preference in getting improvements for erosion and corrosion simulations- determinations in general tribology, biotribology and tribocorrosion. The method(s) developed are classical numerical optimization settings for objective functions, programming optimization and simulations, and special software for imaging in 3D. Results are diverse and the range of their applications is wide. First, the article provides a definite formal demonstration of the nonlinear graphical optimization both in numerical results and in imaging. Then, the authors propose the development of programming optimization and mathematical proofs-algorithms of the integral-differential model for various models. Subsequently, an overview of stochastic erosion methods based on Markov Chain is presented in the article. Finally, the second generation of tribology models is defined and conceptually explained. To summarise, the article comprises new findings towards modernization of tribology, biotribology and tribocorrosion models, gathering innovative research branches for future extension of the mathematical modelling progress. The results can be applied to both general techniques and mechanical engineering. The analytical and numerical demonstration of the integral-differential model constitutes a key point and essential result of the research. Extension to electromagnetic and electronic models of these methods is also considered feasible and practical

Schlüsselwörter

  • engineering reliability operational probabilities
  • functional power plants
  • inverse problem theory/applications
  • nonlinear optimization
  • power engineering
Open Access

An attempt of finding an appropriate number of convolutional layers in cnns based on benchmarks of heterogeneous datasets

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 51 - 57

Zusammenfassung

Abstract

An attempt of finding an appropriate number of convolutional layers in convolutional neural networks is made. The benchmark datasets are CIFAR-10, NORB and EEACL26, whose diversity and heterogeneousness must serve for a general applicability of a rule presumed to yield that number. The rule is drawn from the best performances of convolutional neural networks built with 2 to 12 convolutional layers. It is not an exact best number of convolutional layers but the result of a short process of trying a few versions of such numbers. For small images (like those in CIFAR-10), the initial number is 4. For datasets that have a few tens of image categories and more, initially setting five to eight convolutional layers is recommended depending on the complexity of the dataset. The fuzziness in the rule is not removable because of the required diversity and heterogeneousness

Schlüsselwörter

  • convolutional neural networks
  • convolutional layers
  • error rate
  • hyperparameters
  • performance
Open Access

Adaptive quadrilateral distance relaying scheme for fault impedance compensation

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 58 - 70

Zusammenfassung

Abstract

Impedance reach of numerical distance relay is severely affected by Fault Resistance (RF), Fault Inception Angle (FIA), Fault Type (FT), Fault Location (FL), Power Flow Angle (PFA) and series compensation in transmission line. This paper presents a novel standalone adaptive distance protection algorithm for detection, classification and location of fault in presence of variable fault resistance. It is based on adaptive slope tracking method to detect and classify the fault in combination with modified Fourier filter algorithm for locating the fault. To realize the effectiveness of the proposed technique, simulations are performed in PSCAD using multiple run facility & validation is carried out in MATLAB® considering wide variation in power system disturbances. Due to adaptive setting of quadrilateral characteristics in accordance with variation in fault impedance, the proposed technique is 100 % accurate for detection & classification of faults with error in fault location estimation to be within 1 %. Moreover, the proposed technique provides significant improvement in response time and estimation of fault location as compared to existing distance relaying algorithms, which are the key attributes of multi-functional numerical relay

Schlüsselwörter

  • computer numerical control
  • discrete Fourier transforms
  • electrical fault detection
  • phasor measurement
  • power system faults
  • power system protection
Open Access

Considerations regarding the concept of cost-effective power-assist wheelchair subsystems

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 71 - 80

Zusammenfassung

Abstract

The present paper deals with the concept of a cost-effective power-assistant wheelchair. An analysis of the market situation and recent technical achievements is done at the beginning. On its basis, a set of solutions suitable for the development of such wheelchairs has been composed. It is shown that the key features of the considered concept are: segmented electrical motor and drive, sectioned battery pack, modular charger and an ANN matrix that provides easy and intuitive interfacing of sensor networks, pseudo-bionic feedbacks and the decision-making unit. Within the scope of the paper, a 3D model has been developed and 3D modelling has been conducted. As a result, certain drawbacks in the design and placement of elements have been found and a modification of the concept has been proposed

Schlüsselwörter

  • artificial neural networks
  • batteries
  • electrical drives
  • human-machine interface
  • medical control systems
Open Access

Development case study of the first estonian self-driving car, iseauto

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 81 - 88

Zusammenfassung

Abstract

The rapid development of intelligent control technology has also brought about changes in the automotive industry and led to development of autonomous or self-driving vehicles. To overcome traffic and environment issues, self-driving cars use a number of sensors for vision as well as a navigation system and actuators to control mechanical systems and computers to process the data. All these points make a self-driving car an interdisciplinary project that requires contribution from different fields. In our particular case, four different university departments and two companies are directly involved in the self-driving car project. The main aim of the paper is to discuss the challenges faced in the development of the first Estonian self-driving car. The project implementation time was 20 months and the project included four work packages: preliminary study, software development, body assembly and system tuning/testing of the self-driving car. This paper describes the development process stages and tasks that were distributed between the sub-teams. Moreover, the paper presents the technical and software solutions that were used to achieve the goal and presents a self-driving last mile bus called ISEAUTO. Special attention is paid to the discussion of safety challenges that a self-driving electrical car project can encounter. The main outcomes and future research possibilities are outlined

Schlüsselwörter

  • automotive engineering
  • autonomous vehicles
  • vehicle driving
  • vehicle safety
Open Access

Simulation study of mixed pressure and flow control systems for optimal operation of centrifugal pumping plants

Online veröffentlicht: 28 Jul 2018
Seitenbereich: 89 - 94

Zusammenfassung

Abstract

A Simulink/DriveSize based model for the mutual pressure and flow control of a centrifugal pumping plant with a variable speed drive is proposed. The model provides the possibility of power calculation during both throttling and speed control and to estimate the optimal working point according to these calculations. The model is developed to provide the possibility of power reduction during pressure and flow maintenance with the help of mixed pressure control strategy. To evaluate the system, a series of experiments have been conducted. After the validation of the proposed model through testing, which proved that the designed system is more beneficial from the power consumption point of view than the traditional pressure control methods, it can be stated that the system is useful for pressure and flow control optimization of the centrifugal pumping plants

Schlüsselwörter

  • centrifugal pump
  • MATLAB
  • modelling
  • power measurement
  • variable speed drive

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