Optimization and Measuring Techniques for Collect-and-Place Machines in Printed Circuit Board Industry

This thesis considers optimization problems arising in printed circuit board assembly. Especially, the case in which the electronic components of a single circuit board are placed using a single placement machine is studied. Although there is a large number of different placement machines, the use of collect-and-place -type gantry machines is discussed because of their flexibility and increasing popularity in the industry. Instead of solving the entire control optimization problem of a collect-andplace machine with a single application, the problem is divided into multiple subproblems because of its hard combinatorial nature. This dividing technique is called hierarchical decomposition. All the subproblems of the one PCB - one machine -context are described, classified and reviewed. The derived subproblems are then either solved with exact methods or new heuristic algorithms are developed and applied. The exact methods include, for example, a greedy algorithm and a solution based on dynamic programming. Some of the proposed heuristics contain constructive parts while others utilize local search or are based on frequency calculations. For the heuristics, it is made sure with comprehensive experimental tests that they are applicable and feasible. A number of quality functions will be proposed for evaluation and applied to the subproblems. In the experimental tests, artificially generated data from Markov-models and data from real-world PCB production are used. The thesis consists of an introduction and of five publications where the developed and used solution methods are described in their full detail. For all the problems stated in this thesis, the methods proposed are efficient enough to be used in the PCB assembly production in practice and are readily applicable in the PCB manufacturing industry.

Analytic evaluation of three-phase short circuit demagnetization and hysteresis loss risk in rotor-surface-magnet Permanent-Magnet Synchronous Machines

Permanent magnet synchronous machines (PMSM) have become widely used in applications because of high efficiency compared to synchronous machines with exciting winding or to induction motors. This feature of PMSM is achieved through the using the permanent magnets (PM) as the main excitation source. The magnetic properties of the PM have significant influence on all the PMSM characteristics. Recent observations of the PM material properties when used in rotating machines revealed that in all PMSMs the magnets do not necessarily operate in the second quadrant of the demagnetization curve which makes the magnets prone to hysteresis losses. Moreover, still no good analytical approach has not been derived for the magnetic flux density distribution along the PM during the different short circuits faults. The main task of this thesis is to derive simple analytical tool which can predict magnetic flux density distribution along the rotor-surface mounted PM in two cases: during normal operating mode and in the worst moment of time from the PM’s point of view of the three phase symmetrical short circuit. The surface mounted PMSMs were selected because of their prevalence and relatively simple construction. The proposed model is based on the combination of two theories: the theory of the magnetic circuit and space vector theory. The comparison of the results in case of the normal operating mode obtained from finite element software with the results calculated with the proposed model shows good accuracy of model in the parts of the PM which are most of all prone to hysteresis losses. The comparison of the results for three phase symmetrical short circuit revealed significant inaccuracy of the proposed model compared with results from finite element software. The analysis of the inaccuracy reasons was provided. The impact on the model of the Carter factor theory and assumption that air have permeability of the PM were analyzed. The propositions for the further model development are presented.

27-8-20, circuit de la Sarthe, Isodi sur Douglas : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60711

27-8-20, circuit de la Sarthe, motos Douglas (équipe) [Alexander, Isodi, Kickam] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60713

27-8-20, circuit de la Sarthe, Kickam sur Douglas : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60714

27-8-20, circuit de la Sarthe, Marc sur Thomann : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60715

26-8-20, circuit de la Sarthe, H. Bartlett sur Verus : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60716

27-8-20, circuit de la Sarthe, Dubost sur Motosolo I : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60717

26-8-20, circuit de la Sarthe, Alexander sur Douglas : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60718

27-8-20, circuit de la Sarthe, Vulliamy sur Alcyon : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60719

26-8-20, circuit de la Sarthe, Borgotti sur A.B.C. : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60720

26-8-20, circuit de la Sarthe, A. Milland sur Motosacoche : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60721

26[-08-20] circuit de la Sarthe, A. Robert sur Motosacoche : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60722

26-8-20, circuit de la Sarthe, Morel sur Blériot : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60723

26-8-20, circuit de la Sarthe, Lavanchy sur Blériot : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60724