Arquitetura de Software Embebida

Durante muito tempo considerou-se que o segredo para reduzir o tempo de projeto em sistemas embebidos era iniciar o processo de projeto do software com antecedência...

Virtualization and Embedded System Software Architectures

On Embedded Software Architecture, all the benefits given by the Embedded System Software Architectures (ESSA) were already highlighted. Now, we will discuss how the use of an ESSA in a virtual environment can speed up the development of the products and reduce costs.

Are modular ups systems really more reliable?

UPS are designed to protect critical loads from electrical disturbances that commonly occur in mains supplies: voltage variations (overvoltages, undervoltages, surges), slow or transient frequency variations, power outages and micropower outages (blackouts), voltage sags, voltage spikes, harmonics, high-frequency noise and voltage flickers.

Harmonics: causes, effects and minimization

The main representation of power quality is the harmonic distortion, which represents the deviation between the ideal sinusoidal waveform the network voltage or the load current should have, and what really it is. The harmonics mitigation can report quantifiable benefits for industry critical processes, IT systems, datacenters, etc., in terms of overall installation cost, energy bill reduction, and protection against process interruptions and equipment faults.

Sistemas automáticos de verificação do hardware

Um dos objetivos mais importantes, para não dizer o mais importante, de um novo produto é ser o melhor do mercado, sobretudo em termos de qualidade e de especificações oferecidas. Uma boa qualidade não se consegue apenas com um bom projeto do departamento de I&D...

DC Systems

DC power supplies are an essential part of many industrial applications such as rail systems, telecommunications, energy distribution, energy production plants, etc.

Embedded System Software Architectures In Multiprocessor Systems

In previous documents, the advantages of using Embedded System Software Architectures (ESSA) were highlighted. In the present one we will address, in an introductory way, the role that these architectures can play in systems with more than one processor, which, as we said, are increasingly common.

The "DROOP" method, beyond simply paralleling UPS systems

This paper presents the fundamental methods for controlling UPS connected in parallel, especially the evolution of methods based on droop control.

Three-level NPC inverter used in UPS

The requirements in reliability and capacity are increasing in various industrial applications. Such as the medium voltage uninterruptible power system (UPS) which is widely used for high speed elevators, high-power electric drives and distributed generation systems as an interface between the utility grid and distributed power sources. With the fast development of power converter technologies, multilevel converters are good choice for medium voltage industrial applications. Normally, the multilevel inverters are classified into three kinds, namely the neutral point clamping (NPC) multilevel inverter, the flying capacitor multilevel inverter and the cascaded H bridge multilevel inverter. Among them, the NPC three-level (NPC-3L) inverter has attractive features of simple configuration and control scheme, and these features make it attractive in both academia and industry.

Differential protection in photovoltaic inverters

Mains-connected photovoltaic inverters require EMI filters to suppress the electromagnetic interference generated by the device. Without these filters, the interference would filter to the electricity grid, in breach of current regulations. Their use helps avoid these filtrations, although this in turn introduces earth leakage currents due to the existence of capacitors between phases and earth that involve leaks when powered. These leakage currents, along with those of different loads that EMC filters might carry, which may increase if the facility is equipped with power converters that switch to high frequency, in addition to the earthing capacity of the photovoltaic panels which can also produce leakage currents, may cause the sudden undesirable tripping of the differential protection if the sensitivity threshold of the residual current device installed is exceeded, thus highlighting the importance of choosing the correct residual current device for installation as electric shock protection in the photovoltaic plant. The document expounds the recommendation by SALICRU regarding the type and sensitivity of the necessary differential protection in the facility of its inverters, and the regulations on which it is based.

Integration of control loops in energy management systems

In a world marked by climate change and the constant increase in energy consumption, photovoltaic solar power emerges as one of the most powerful and necessary solutions to face the challenges of the 21st century. In this scenario of exponential growth in distributed generation and electricity demand, there is a key element in every photovoltaic installation that takes centre stage: the energy manager. This control device acts as the brain of the plant, managing its behaviour through advanced control methods to ensure compliance with current regulations. It is a device capable of analysing, controlling and optimising in real time the operation of one or several generation units (solar inverters), maximising the performance of self-consumption and ensuring optimal integration with the distribution grid.