The Journal of Engineering
Volume 2016, Issue 4, April 2016
Volumes & issues:
Volume 2016, Issue 4
April 2016
Adaptive predictive error filter-based maximum power point tracking algorithm for a photovoltaic system
- Author(s): Bidyadhar Subudhi and Raseswari Pradhan
- Source: The Journal of Engineering, Volume 2016, Issue 4, p. 54 –61
- DOI: 10.1049/joe.2015.0195
- Type: Article
- + Show details - Hide details
-
p.
54
–61
(8)
This study presents a new adaptive predictive error filter-based maximum power point tracker (MPPT) for a photovoltaic (PV) system. This MPPT is developed using the concept of an adaptive predictive filter (APEF) that consists of a one-tap finite impulse response. The filter step-size of the APEF is adapted using a recursive least-square (RLS) algorithm with an adaptive forgetting factor. The specialty of this MPPT is that it performs MPP tracking operation in a single step. It performs two functions: namely, MPP estimation adjusting operating point of a boost converter at MPP and then filtering of the PV voltage fluctuation after MPPT action. Thus, the proposed MPPT is compact and efficient with less computational complexities than existing MPPTs such as perturb and observe (P&O) and incremental conductance. The filter part of the proposed RLS-APEF-MPPT is a discrete PID-controller, where PD-part is tuned using pole-placement strategy and integral-term is fixed. The performances of the proposed RLS-APEF-MPPT were verified using experimentation on a prototype PV system. Its performances were compared with that of P&O, adaptive-P&O-MPPTs. From the observed results, it is confirmed that the proposed MPPT exhibits superior performance.
Built-in self-monitor-based finite state machines Trojans detection and self-lock defence
- Author(s): Yongkang Tang and Jianye Wang
- Source: The Journal of Engineering, Volume 2016, Issue 4, p. 62 –63
- DOI: 10.1049/joe.2016.0012
- Type: Article
- + Show details - Hide details
-
p.
62
–63
(2)
Synthesising circuits through general finite state machines design implement transitions from do not-care states to effective ones or themselves. Also, outsourcing integrated circuit specifications to foundries provides adversaries opportunities to build transitions from effective states to do not-care ones. Two security vulnerabilities above can bring finite state machines Trojans (FSMTs) to original circuits. In this Letter, a built-in self-monitor-based approach is proposed to detect FSMTs at runtime and return warning signals, thereby achieving self-lock defence. Finally, the proper solutions are proposed to solve two existing arguments about the authors’ approach.
Harmonic assessment-based adjusted current total harmonic distortion
- Author(s): Shady H.E. Abdel Aleem ; Ahmed M. Ibrahim ; Ahmed F. Zobaa
- Source: The Journal of Engineering, Volume 2016, Issue 4, p. 64 –72
- DOI: 10.1049/joe.2016.0002
- Type: Article
- + Show details - Hide details
-
p.
64
–72
(9)
Power systems suffer from harmonic distortion and extra ohmic losses associated with them. Moreover, all harmonic frequencies are mostly assumed to have the same effect on the system losses. However, the frequency-dependency of the resistances should be taken into account, so that the apparent power and the power factor have to considerably reflect power losses under non-sinusoidal conditions. In this study, the difference between unweighted and weighted non-sinusoidal losses is addressed. A new harmonic-adjusted total harmonic distortion (THD) definition is proposed for both voltage and current. Besides, a new formula that relates the proposed harmonic-adjusted THD and a generalised harmonic derating factor definition of the frequency-dependent losses of the power transmission and distribution equipment is derived. An optimal C -type passive filter design for harmonic mitigation and power factor correction based on the minimisation of the proposed harmonic-adjusted THD for a balanced non-sinusoidal system is introduced. A comparative study of the proposed filter design based on the new harmonic-adjusted definition, and a conventional filter design based on standard THD definition, is presented.
Modelling short- and open-circuit faults in permanent magnet synchronous machines using Modelica
- Author(s): Paolo Giangrande ; Luca Papini ; Chris Gerada
- Source: The Journal of Engineering, Volume 2016, Issue 4, p. 73 –79
- DOI: 10.1049/joe.2016.0016
- Type: Article
- + Show details - Hide details
-
p.
73
–79
(7)
Electrical machine models are indispensable for describing and predicting the machine behaviour in several operating conditions. Modelling fault conditions are an attractive research area, since fault simulations allow to figure the behaviour of the electric drive and prevent damages to its components. In this study, winding failures in permanent magnet synchronous machines (PMSMs) are considered. In particular, short-circuits and open-circuits failures have been taken into account via two simple PMSM models. These models have been created using Modelica as modelling language. Feasibility of the proposed models is investigated in simulation (using Dymola environment) under the following fault conditions: single-phase open-circuit, single- and three-phase short-circuits. Moreover, models validation has been carried out through experimental tests, injecting windings failures into a fault-tolerant PMSM.
Practical approach to facilitate photovoltaic integration in distribution systems
- Author(s): Jalil Yaghoobi ; Nadarajah Mithulananthan ; Tapan Kumar Saha
- Source: The Journal of Engineering, Volume 2016, Issue 4, p. 80 –87
- DOI: 10.1049/joe.2016.0031
- Type: Article
- + Show details - Hide details
-
p.
80
–87
(8)
Photovoltaic (PV) power is a promising source of renewable energy, which could satisfy a large portion of the authors’ electricity needs. In order to achieve this, a high penetration of PV is required as it is limited in plant factor and its characteristics are completely different from the conventional generators. However, high penetration level might cause some problems for the network operation. One of the potential setbacks that have been widely reported by power utilities is a voltage rise due to reverse power flow. Considering this burning problem, this study develops a practical method based on power flow formulation. In this method, two matrices are derived for estimating the effect of PV real and reactive power injections on the system voltage profile. These simple scalar matrices are then applied to find the voltage sensitive buses and the optimum location and sizing for power compensation devices to improve the penetration level of PV. Comparison between actual and estimated results for IEEE 37-bus test system justifies the validity of proposed method for these applications.
Durer-pentagon-based complex network
- Author(s): Rui Hou ; Yuejiana Chang ; Yuzhou Chang
- Source: The Journal of Engineering, Volume 2016, Issue 4, p. 88 –91
- DOI: 10.1049/joe.2015.0139
- Type: Article
- + Show details - Hide details
-
p.
88
–91
(4)
A novel Durer-pentagon-based complex network was constructed by adding a centre node. The properties of the complex network including the average degree, clustering coefficient, average path length, and fractal dimension were determined. The proposed complex network is small-world and fractal.
Compact branch-line coupler with meander high-impedance transmission line and port impedance matching
- Author(s): Jun He and Bing-Zhong Wang
- Source: The Journal of Engineering, Volume 2016, Issue 4, p. 92 –93
- DOI: 10.1049/joe.2016.0023
- Type: Article
- + Show details - Hide details
-
p.
92
–93
(2)
A novel compact branch-line coupler with meander high-impedance transmission line and port impedance matching is presented in this study. The proposed circular coupler effectively reduces occupied area to 29.1% of conventional rectangular one. The design is validated both by simulation and measurement.
Most viewed content
Most cited content for this Journal
-
Towards good practice guidelines for the contour method of residual stress measurement
- Author(s): Foroogh Hosseinzadeh ; Jan Kowal ; Peter John Bouchard
- Type: Article
-
Mutual capacitor and its applications
- Author(s): Chun Li ; Jason Li ; Jieming Li
- Type: Article
-
Investigation of wound rotor induction machine vibration signal under stator electrical fault conditions
- Author(s): Sinisa Djurović ; Damian S. Vilchis-Rodriguez ; Alexander Charles Smith
- Type: Article
-
Techno-economic analysis of a PV–wind–battery–diesel standalone power system in a remote area
- Author(s): Temitope Adefarati ; Ramesh C. Bansal ; Jackson John Justo
- Type: Article
-
Survey of buffer management policies for delay tolerant networks
- Author(s): Sweta Jain and Meenu Chawla
- Type: Article