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The purpose of this paper is to present issues related to the design of a modern lighting system based on LED technology. The developed system provides lighting with a high colour rendering index (up to 98); it also has many innovative functions, which make its implementation bring significant energy savings and increase the comfort of work.

In contrast to typical solutions, the dynamic synthesis of white light from six component colours was used in the presented project. This process is controlled by a microcontroller, and there is a colour temperature sensor in the feedback loop. The communication between smart luminaires and sensor modules is provided by means of a ZigBee wireless network.

The correctness of the proposed methodology has been proved by measurements and laboratory tests.

The process of improving the lighting system is continued and significant changes in the spectrum of used sensors are expected.

The proposed system based on mixing light from six components is an innovative solution that besides undoubted advantages entails a more elaborate electronic circuitry. However, good characteristics of the obtained light, as well as the possibility of compensating for changes in colour temperature of natural light and reducing the impact of aging of LEDs, in the authors’ opinion, make the proposed solution find its place on the market.

The proposed solution is original, both in terms of the light mixing technique and advanced functionality offered by the system.

The purpose of this paper is to report the system solution expressed in the form of a block diagram. In this paper, a multi-functional demonstrator of the interactive system designed to modelling, monitoring and validation of hybrid photovoltaic (PV) systems assisted by fuel cells and thermoelectric generators is presented. Technical parameters of demonstrator components such as: silicon PV modules, fuel cells, thermoelectric generators, gel batteries, control and monitoring systems are described.

The design shows the implementation of PV system modelling by four universal PV module simulators supported by two 65 W fuel cell and 12 modules, 6 W thermoelectric generators battery.

The paper provides practical proof that the combination of PV technology with both thermoelecric generators and fuel cells technologies shows promising results for the development of hybrid PV systems with increased effectiveness and efficiency.

The design idea can be developed for many applications gaining electricity from many distributed sources of wasted energy.

In practice, hybrid systems can be used to support the operation of classic PV systems, for example, working in various climatic conditions.

The proposed model demonstrates new technical solution leading to the enlargement of the PV systems application.

This paper aims to present certain issues in direct bonded copper (DBC) technology towards the manufacture of Al2O3 or AlN ceramic substrates with one or both sides clad with a copper (Cu) layer.

As part of the experimental work, attempts were made to produce patterns printed onto DBC substrates based on four substantially different technologies: precise cutting with a diamond saw, photolithography, the use of a milling cutter (LPKF ProtoMat 93s) and laser ablation with differential chemical etching of the Cu layer.

The use of photolithography and etching technology in the case of boards clad with a 0.2-mm-thick Cu layer, can produce conductive paths with a width of 0.4 mm while maintaining a distance of 0.4 mm between the paths, and in the case of boards clad with a 0.3-mm-thick copper layer, conductive paths with a width of 0.5 mm while maintaining a distance of 0.5 mm between paths. The application of laser ablation at the final step of removing the unnecessary copper layer, can radically increase the resolution of printed pattern even to 0.1/0.1 mm. The quality of the printed pattern is also much better.

Etching process optimization and the development of the fundamentals of technology and design of power electronic systems based on DBC substrates should be done in the future. A limiting factor for further research and its implementation may be the relatively high price of DBC substrates in comparison with typical PCB printed circuits.

Several examples of practical implementations using DBC technology are presented, such as full- and half-bridge connections, full-wave rectifier with an output voltage of 48 V and an output current of 50 A, and part of a battery discharger controller and light-emitting diode illuminator soldered to a copper heat sink.

The paper presents a comparison of different technologies used for the realization of precise patterns on DBC substrates. The combination of etching and laser ablation technologies radically improves the quality of DBC-printed patterns.

The aim of the research was to find out a method of adaptive speed control robust against variation of selected parameters of system like moment of inertia, time constant of torque control loop or torque coefficient of the motor.

The main goal of the research was achieved due to application of artificial neural network (ANN), which was trained on line on the base of speed control error. The good results were gained by elaboration of enough fast and precise training algorithm and proper ANN structure.

The work shows a structure of artificial neural network (ANN), applied as adaptive speed controller, and presents an algorithm of ANN training. Some versions of this algorithm were analysed and verified by simulation and experimental tests.

The research should be continued to determine a final version of training algorithm and its influence on controller properties.

The elaborated adaptive controller can be easily used by applying microprocessor system available now on the market. The proposed control solution is robust against parameters variation as well as their imprecise identification. The controller has ability of self‐tuning which can have great practical advantage.

Social implications are difficult to determine.

The paper presents a new solution of adaptive speed controller, which means a new ANN structure and new training algorithm.