An Efficient High-Frequency Discrete Controller for Solar Powered Boost Converter

Abstract

In this paper, Delta operator based Discrete Sliding Mode Fuzzy Control (Delta-DSMFC) strategy is introduced for solar powered boost converter so that the output tracks the reference even at high-frequency. Furthermost methods realized to find MPPT have some disadvantage like the fluctuation around the operating point. Therefore, there is a requirement to obtain maximum solar energy by tracking the maximum power point robustly. This paper proposes a discrete control technique that is implemented to boost converter in order to overcome this problem. It is well established that the Discrete Sliding Mode Controller could be successfully used to control output voltage of the DC-DC converters where the system response is slow and introduces chattering problem. However, there may be a possibility of loss of information during fast sampling. In order to address the performance issue and avoid the loss of information when operating under high frequency, delta operator has been introduced. With the use of this operator, which has distinct mathematical property, the response of the converter is improved even at faster sampling rate. One more advantage of using delta operator is that it can convert analog signal to digital and vice-versa at high efficiency. The chattering problem is overcome by the introduction of fuzzy controller to tune the gain. Overall benefit of using this control technique is that it improves the overall efficiency by reducing the ripple current and improving rise time of the system. With the usage of renewable resource, the system is economical.