MODELLING OF VTS SUPERVISOR BY ALGORITHM BASED ON PETRI NET: CASE STUDY OF DOVER INCIDENT

The paper deals with collision prevention problem in maritime transport in the area of the narrow canals with predefined routes. The Dover incident, which is analysed and described in the paper, has shown that the control of the passage of ships through the critical areas must be upgraded with an automatic supervising system, which warns the human operator of incorrect ship motion and help the operator to make the right and timely decision. The general idea is to improve the safety of navigation by introduction of automatic collision prevention based on automated supervisor helping to human operator in Vessel Traffic System (VTS) control centre. The VTS supervisor automatically monitors marine traffic by using data from Automatic Radar Plotting Aid (ARPA) radar and others sensors. Such supervisor detects real time and Course Over Ground (COG) of the vessel entering a particular sector, and then estimates the required time for vessel’s passage into another sector. VTS supervisor compares the real time and estimated time of passage of the specific ship through particular sector as a part of surveillance area. In addition, it compares and monitors the deviation of the course during transition of zones (sectors). If significant difference for both values are occurred VTS supervisor triggers a time alarm or a course alarm respectively. In the paper authors have modelled and simulated collision prevention with performed by the alarm actions of VTS supervisor improved with algorithm module based on hybrid Petri net formalism and Visual Object Net ++ tool.

Management of Hybrid Renewable Energy Systems Using Differential Hybrid Petri Nets

Investigations in this paper concern management of Hybrid Renewable Energy systems. To achieve it, a supervisory system based on hybrid systems concept is designed, in order to ensure power flow between energy generators (solar panel and pico-hydroelectric), batteries and load. Differential Hybrid Petri Net is used to model the proposed supervisory and simulations are made in Matlab environment.Results obtained present a good performance criteria Loss of Power Supply Probability, and this show the effectiveness of our approach in the coordination of HREs components during the energy sharing process by reducing load shedding in microgrid system.

Application of Hybrid Petri Nets for the Energy Dispatching of an Isolated Micro-Grid

Renewable energy-based autonomous installations sometimes have an energy deficiency or excess caused by the intermittence of renewable sources and the dynamics of the load. Storage systems are unable to cover load supply during long weather instability. In case of neighboring autonomous installations, some have a lack of energy while neighbors have overproduction. Hence, interconnecting installations via a micro-grid (MG) should allow supply installations experiencing an energy lack by sending them energy surplus from others. This article presents a Hybrid Petri Net (HPN) strategy for a micro-grid energy provider in order to make hourly decisions on dispatching energy between the connected installations. An HPN model combines discrete events (house energy state) and continuous events (energy flow) to cover the need of some installations by energy surplus offered by its neighbours. The algorithm has been validated for three connected houses with different load profiles. Results show that installations cover each other in energy without the need to refer to their batteries in case of a lack of energy.

AMS SoC Formal Verification based on Hybrid Scheme

This paper proposes for AMS SoC formal verification based on Hybrid Scheme combined with symbolic computing and LHPN model, FV-HS. The paper is concerned with a class of AMS designs, continuous-time AMS designs i.e., tunnel diode oscillator for research target. Firstly, Labeled Hybrid Petri Net model is established for safety property verification of tunnel diode oscillator, then mathematical expression for this model is extracted for efficiency enhancement, and then proof policy built in computer algebra Maple is applied to the corresponding LHPN model for tunnel diode oscillator to verify the property. The proposed method is implemented on tunnel diode oscillator and experiment results demonstrate the advantages of the proposed method over previous method. The proposed method overcomes the drawbacks of LHPN, makes full use of the merits of LHPN and symbolic computing, simplifies the workflow of algorithm and enhances the efficiency.