Modular Hybrid Energy Concept Employing a Novel Control Structure Based on a Simple Analog System

This paper proposes a novel control topology which enables the setup of a low cost analog system leading to the implementation of a modular energy conversion system. The modular concept is based on hybrid renewable energy (solar and wind) and uses high voltage inverters already available on the market. An important feature of the proposed topology is a permanently active current loop, which assures short circuit protection and simplifies the control loops compensation. The innovative analogue solution of the control structure is based on a dedicated integrated circuit (IC) for power factor correction (PFC) circuits, used in a new configuration, to assure an efficient inverter start-up. The energy conversion system (control structure and maximum power point tracking algorithm) is simulated using a new macromodel-based concept, which reduces the usual computational burden of the simulator and achieves high processing speed. The proposed novel system is presented in this article from concept, through the design and implementation stages, is verified through simulation and is validated by experimental results

Software Solution for a Renewable Energy Microgrid Emulator

The paper presents a software solution and communication network used to implement and test management algorithms for different microgrid configurations. The results obtained are represented in a Graphical User Interface (GUI). Data is transferred between the devices and a central processing unit that has a communication protocol interpreter implemented using an RS-485 network. After being interpreted, the raw data containing useful information for the management algorithm is converted in numerical or Boolean values. These values are stored and used by the management algorithms implemented for cost optimization. A microgrid emulator is used for the proof of concept. The software solution and communication network together with the data interpreter can be easily used for other microgrid structures with or without modifications, depending on the number and types of equipment used. In the presented case the microgrid management control algorithm tries to keep the state of charge of the batteries between two values by using efficiently the available resources depicted by: solar energy, geothermal energy, and energy obtained from biomass. The microgrid setup has emulators for the geothermal and biomass generators and a photovoltaic system with storage capability and two inverters, a grid forming capable and a grid follower

Photovoltaic System with Smart Tracking of the Optimal Working Point

A photovoltaic (PV) system, based on a Maximum Power Point Tracking (MPPT) controller that extracts the maximum possible output power from the solar panel is described. Output efficiency of a PV energy system can be achieved only if the system working point is brought near the maximum power point (MPP). The proposed system, making use of several MPPT control algorithms (Perturb and Observe, Incremental conductance, Fuzzy Logic), demonstrates in simulations as well as in real experiments good tracking of the optimal working point

An Indirect Method and Equipment for Temperature Monitoring and Control

A new temperature control method for a metallic filament used at high temperature values is proposed by the authors in this paper. The filament used is heated by a switch mode power supply built around a step-down converter. The method uses a microcontroller that implements the temperature control algorithm and also the power supply control loops. The temperature is controlled using a proposed new algorithm based on the output current and output voltage measurements of the power supply already available for implementing the average current mode control. In this way the resistance of the filament can be determined and controlled in a resistance feedback loop. The proposed algorithm will control the resistor value corresponding to the required temperature. The reference resistance value is computed based on the temperature-resistance characteristic of the filament each time a new temperature is introduced in dedicated computer software on a PC. The value is transmitted to the microcontroller via USB interface. The temperature control algorithm and experimentally results are presented in detail in the paper