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AbstrrrcC The paper describes a tool developed to automate the study of solar array configurations u h g a general-purpose simulntor such PJ Spice. Tbe main advantage of the proposed method b that studies can be done for any solar array configurntion formed from eIementnry models of solar cell units. Hierarchid structure o f solar cell elements with semiconductor d e U allows simulations of electrical properties as well as evaluation of environmental conditions impact AppHution exnmples such ns the effect of unequal illuminntion on various array interconnections and the mismatch of mlnr cells will be presented to demonstrate the usefulness of the tool. The automated proeess will ease investigation of large syatem and wontcase study for given envfronmentnl scenarios. 1.MTRODUCI'iON The understanding of solar cell source behavior is necessary to specify the size of solar array system or to study the stability of regulators. Placing the solar panels in an optimal way i s an effective measure to take to maximize the energy yield from a photovoltaic-installation. Any shading of the solar panels will lead to considerable reduction in energy yield, even if just a small fraction of the panels i s shaded. Shading can m I y be completely avoided, certainly not in urban or suburban environments. At higher latitudes the sun is often close to the horizon which makes the shading problem more severe than at low latitudes. Therefore especially for high-latitude locations and tubadsuburban sites, a shadingtolemnt system should be chosen. Furthermore, the direction southhorth (azimuth) and elevation angle should also be considered.The connection of photovoltaic modules with different operating currents andlor voltages characteristic may result in the performance of the anay being less than the sum of the potential performances of individual modules. When connected in series, the current flowing through the lowest productive cell limits the entire array output. The problem arises when modules have different sizes, which may be a result of individual modules not exposed to the same lighting conditions, such as is the case with differently oriented modules or irregular shading of the array. Mismatch is more likely in large systems than in independent arrays, because individual modules may be oriented differently or they may be subject to varying degrees of shading and heating.Taking into account that real operating conditions of a solar array are difficult to reproduce during tests, simulations to determine electrical characteristics will allow the researcher to gain more insight for better understanding and design. Performance gain is beneficial and can find applications in numerous areas such as the one described in reference [I]. AS the fine modeling of a cell's behavior is the basis for any solar generator, the solar cell model needs to be properly determined. Methods for simulation of general solar amy configuration have been proposed, however, these implementations are associated with special-purpose simulation tools, and detai...

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Many of the new high-speed high-integration density Integrated Circuits (ICs) and future generation of microprocessor powering requirements can be successfully achieved with voltage-mode hysteretic control applied to interleaved multiphase Point-of-Load (POL) DC-DC converters or Voltage Regulator Modules (VRMs). This is because of the several advantages that can be achieved by combining the advantages of hysteretic control and interleaving. However, there are several challenges in combining the two techniques, the most prominent being the current sharing and equalization between the interleaved phases. In this communication, we present a solution based on a real-time DSP controller. Challenges of the implementation will be discussed and experimental results obtained from a prototype will be presented.