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This chapter presents the application of a particle swarm optimization (PSO) to a controller tuning in selected power electronic and drive systems. The chapter starts with a relatively simple tuning of a cascaded PI speed and position control system for a BLDC servo drive. This example serves as the background for a discussion on selecting the objective function for the PSO. Then the PSO is used in two challenging controller tuning tasks. This includes optimizing selected learning parameters in the adaptive artificial neural network (ANN) based online trained speed controller for an urban vehicle (3D problem) and selecting penalty factors in the LQR with augmented state (i.e. with oscillatory terms) for a three-phase four-leg sine wave inverter (15D problem). It is demonstrated with the help of these case studies why and where the PSO, or any other similar population based stochastic search algorithm, can be beneficial. Engineers encounter many non-straightforward controller tuning problems in power electronic systems and this chapter illustrates that in some cases it is relatively easy to reduce these tasks into the objective function selection problem. The relevant controller parameters are then determined automatically by the PSO.

The paper presents an evolutionary optimization of a novel neurocontroller for the single phase sine-wave inverter. The controller is trained in online mode. The adaptation algorithm takes into account repetitiveness of the process to be controlled. The cost function evaluates performance of the controller over the whole period of the reference signal and the weights are updated only once per period of this signal. A model-free concept is implemented and hence no prior identification of the plant is needed. The controller employs the backpropagation algorithm for updating its weights in order to adapt to changing load conditions. The controller is nonlinear and the tuning procedure involves determining a good set of values for at least three parameters: a number of neurons, an error gain and an output gain. In our recent publication devoted to the development of the control algorithm we relied on guessing and checking at the tuning stage. Here the particle swarm optimizer (PSO) is used to find the optimal set of values for these parameters. The gradientless search algorithm enables a designer to work with any user-defined performance index that reflects desired system behavior. The effectiveness of the proposed approach is illustrated with the help of numerical experiments. The controller tuned by the PSO is capable to maintain a high-quality output voltage waveform in the presence of the periodic disturbance caused by nonlinear loads.

In this paper new discrete non-stationary linear-quadratic speed regulator for PMSM fed by 3-level NPC sinusoidal inverter is presented. Controlled sinus wave inverter with an output LC filter was used in order to reduce electromagnetic torque ripple of the motor. The novelty of the proposed control system consists in one state feedback controller using in order to control the angular velocity of the motor as well as to provide true sine wave of the motor voltages. It was found that some gains of the designed discrete controller are non-stationary and depends on the angular velocity of the motor. Use of non-stationary controller causes, that linearization and decoupling process of the motor with LC filter is not needed. Simulation test results of the designed control system are compared with results obtained for PMSM fed by classical 2-level inverter. Proposed control system can be used in industrial applications where torque ripple minimization is needed instead high dynamic performance.

In this paper three different implementations of the full-state feedback linear-quadratic (LQ) controller for a 3-phase 4-leg sine wave inverter are compared. The LQ controller is designed in stationary reference frames abc and αβγ as well as in a dq0 reference frame rotating with the fundamental output frequency, and is not cascaded with any inner controller. In the proposed control schemes integral and multi-oscillatory terms are added to the input of the LQ controller to ensure high quality output voltage waveforms for unbalanced and nonlinear loads. All three approaches are tested in an experimental inverter (a physical model at the level 10kVA). The experimental results for linear and nonlinear loads are presented, discussed and some remarks on choosing the best reference frame are then given.

This paper presents simulation studies and preliminary experimental results related to a hybrid battery-ultracapacitor energy source for an urban electric car. A proposal of energy management strategy based on fuzzy logic is introduced. Control strategy for the hybrid source is designed to achieve high-efficiency and high-power source for the vehicle with a relatively small battery storage. Simulation studies show the possibility to use information from a navigation system to improve performance of the source.

In this paper we develop a new approach to combined full-state and disturbance feedforward control system synthesis for a three-phase four-leg true sine wave inverter. Proposed scheme is an extension of the augmented state feedback controller with multi-oscillatory terms. Multi-resonant controllers are well-established solution for this kind of converters if high quality output voltage is needed in the presence of nonlinear loads. They take advantage of repetitiveness of the control process under the steady load conditions (this includes nonlinear and unbalanced loads). No presumption on load type entails introduction of oscillatory terms for all three voltage components with resonant frequencies up to available bandwidth dictated by technically justified switching/sampling frequency. This makes the practical implementation challenging. Our idea is to reduce number of needed oscillatory terms by adding disturbance feedforward. In the discussed system the disturbance signal is easily accessible/measurable and hence this feedback can be very effective because of lack of estimation errors. The control system is designed in dq0 reference frame rotating with the fundamental output frequency. Extensive numerical experiments indicate that the number of oscillatory terms can be reduced significantly and high quality of output voltage can be maintained.

The paper investigates possible advantages from using nonlinear adaptive ANN (Artificial Neural Network)-based controller in a control system of autonomous variable speed electrical energy source with internal combustion engine. The speed is adjusted automatically as a function of load power demand. When the system is in a light or no load condition, the Main Voltage Controller automatically reduces the engine speed in order to reduce the fuel consumption, environmental noise and mechanical wear of engine parts. Optimization of the controller is difficult due to the non-linearity and non-stationarity of the plant.

The paper presents control system synthesis for a true sine wave four-leg inverter with an LC output filter. Our main goal is to ensure high quality voltage waveform for unbalanced and nonlinear loads. An LQR approach was chosen. The LQR design approach has proven effective in many industrial applications. Although weights in a cost function are usually set by guess and check method, the LQR in proposed system gives satisfactory results as far as some general and very intuitive rules are applied, e.g. the penalty coefficient for an integral of control error is a few orders of magnitude away from penalty coefficients related to plant state variables. In order to immunise system against nonlinear loads oscillatory terms are included in the control scheme. They can be tuned for typical harmonics like 5th, 7th, 11th and 13th. A novelty of the proposed solution lies in the fact that all controller gains (including all integral and oscillatory terms) are determined altogether in one LQR procedure call. Controls are calculated in rotating reference frame. Simulation (continuous and discrete) and experimental results (at the level of 10kW) are included. They establish consistent set of tests that validates effectiveness of the design approach.

The effects of sub-minimum inhibitory concentrations (sub-MICs) of three antibiotics affecting the biosynthesis of pepti-doglycan on the interactions of Staphylococcus aureus strains with collagenous substrata were evaluated. In a system measuring binding of 125I-labeled collagen, growth of bacteria in the presence of one-quarter MIC of cloxacillin and vancomycin reduced the number of collagen binding sites on the surface of bacteria. Growth in the presence of cefpodoxime reduced the number of collagen binding sites in one strain and increased it in another. Cefpodoxime also increased the dissociation constant of collagen binding to bacteria, 2- to 3-fold, while the other two antibiotics did not affect the affinity of the interaction. In a system measuring adhesion of 125I-labeled bacteria to collagen-coated surfaces or cartilage, bacteria grown in the presence of cloxacillin and vancomycin attached to varying degrees depending on the strain. In contrast, compared to untreated controls as well as to bacteria treated with the other two antibiotics, growth in the presence of cefpodoxime significantly reduced adhesion of the majority of strains tested. Sub-MICs of antibiotics appear to affect staphylococcal adhesion to collagenous substrata with cefpodoxime exhibiting the strongest effect. The critical factor in reducing bacterial adhesion seems not to be the number of bacterial binding sites for collagen, but the affinity of the interaction.

This paper considers iterative learning control law design for bothtrial-to-trial error convergence and along the trial performance in the control system of the single-phase inverter (DC/AC). The inverter with passive LC filter act as a high quality AC power source with sinusoidal output voltage. Such solution is typically used for instance in Uninterruptible Power Supply (UPS) system. Standard feedback control cannot eliminate the periodic distortion caused by nonlinear loads. It is shown how a class of control laws can be designed using thetheory of linear repetitive processes for this problem where thecomputations are in terms of Linear Matrix Inequalities (LMIs).The simulations have been performed with the use of Simulink accompanied by PLECS library, which allows to simulate power electronic converter facilities in their realistic working conditions.

This paper describes a discrete linear quadratic speed regulator (LQR) for permanent magnet synchronous motor design. Linearization and decoupling processes of a motor model were discussed. An internal input model was introduced to control algorithm in order to eliminate the steady state speed error caused by step reference speed as well as load torque variations. Simulation tests of the drive system with the PMSM, were carried out in the Matlab-Simulink environment. The designed discrete control algorithm was implemented in a digital signal processor (TMS320F2812) and tested in a setup system. Simulation and experiment test results confirm properly operation of the designed drive system.

This paper presents a scalable and effective discontinuous pulse width modulation algorithm for multileg converters. The method can also be used in three- and four-leg voltage-source converters, though its simplicity in comparison to so called vector modulators shows up clearly in systems with more than three legs. Some similarities between vector and sinusoidal modulations are discussed and issues regarding naming these methods are raised. Numerical simulation test results are presented.

Periodic abstinence and coitus interruptus are the most popular methods of contraception in Poland. Recent studies have provided us with evidence that the so-called "menstrual calendar" may be much less effective than it was believed. In these circumstances, promotion and use of safe and truly effective contraceptives is very important for Polish women. Emergency contraception (EC) is a method which could be used even in cases when other contraception methods have failed. Mechanism of action of levonorgestrel used for EC and possible disturbances in the process of implantation of the blastocyst in the endometrium, remain the source of heated discussion among medical professionals. The latest publications provide us with evidence that the use of levonorgestrel in EC neither alters endometrial receptivity nor impedes implantation. Hormonal EC effectiveness is another hot topic of gynecological endocrinology and statistics. There is, however, no better, safer, and more ethically accepted method of preventing unwanted pregnancy for patients in need of postcoital contraception.

Today there are very few open source optical network monitoring solutions available for grid users and even network operators. Most of the available optical monitoring solutions are proprietary and single vendor solutions. Even the existing software is often limited in functionality and extremely difficult to apply in a distributed grid environment. grid users can only successfully use optical grid infrastructures spanning over multiple domains if they have efficient monitoring and fault detection tools available to them. In this chapter we present a tool for monitoring wavelengths. Our approach recognizes and facilitates the ability of independent networks to set policies while facilitating the status and performance monitoring by users interested in optical paths connecting distributed resources.

Bacteroides (Porphyromonas) gingivalis, which has been implicated as an etiologic agent in human periodontal diseases, has been shown to bind and degrade human fibrinogen. B. gingivalis strains bind fibrinogen reversibly and with high affinity and bind to a specific region of the fibrinogen molecule that appears to be located between the D and E domains (M. S. Lantz, R. D. Allen, P. Bounelis, L. M. Switalski, and M. Hook, J. Bacteriol. 172:716-726, 1990). We now report that human fibrinogen is bound and then degraded by specific B. gingivalis components that appear to be localized at the cell surface. Fibrinogen binding to bacterial cells occurred at 4, 22, and 37 degrees C. A functional fibrinogen-binding component (Mr, 150,000) was identified when sodium dodecyl sulfate-solubilized bacteria were fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to nitrocellulose membranes, and probed with 125I-fibrinogen. Fibrinogen degradation did not occur at 4 degrees C but did occur at 22 and 37 degrees C. When bacteria and iodinated fibrinogen were incubated at 37 degrees C, two major fibrinogen fragments (Mr, 97,000 and 50,000) accumulated in incubation mixture supernatant fractions. Two major fibrinogen-degrading components (Mr, 120,000 and 150,000) have been identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis in substrate-containing gels. Fibrinogen degradation by the Mr-120,000 and -150,000 proteases was enhanced by reducing agents, completely inhibited by N-alpha-p-tosyl-L-lysyl chloromethyl ketone, and partially inhibited by n-ethyl maleimide, suggesting that these enzymes are thiol-dependent proteases with trypsinlike substrate specificity. The fibrinogen-binding component could be separated from the fibrinogen-degrading components by selective solubilization of bacteria in sodium deoxycholate.