MMQSG Based Power Quality Improvement of Three Phase Solar Energy Conversion System

An active clamped L‐L type ZVS current‐fed front‐end DC–DC converter based solid state transformer in grid connected mode PV applications

“…And, $$$$\begin{equation*}{A_{hn}}{\mathrm{}}\left( s \right) = \frac{{{J_{hn}}\left( s \right)}}{{{K_1}E\left( s \right)}}\end{equation*}$$$$ $$$$\begin{equation} = \frac{{n{K_{1}}{W^2}s}}{{\left( {{s^3} + n{K_{3}}W{s^2} + \left( {1 + \frac{{{K_1}}}{n}} \right){{\left( {nW} \right)}^2}s + {K_{3}}{{\left( {nW} \right)}^3}} \right)}}\end{equation}$$$$where n is the order of the harmonic components at which the DFSEn filter is tuned. Therefore, the final transfer function can be given by [26, 27]: $$$$\begin{equation}{G_{1\alpha }}\left( s \right) = \frac{{{J_\alpha }\left( s \right)}}{{J\left( s \right)}} = {C_1}\left( s \right)\left[ {1 - \mathop \sum \limits_{n = 3,5,7,11} {A_{hn}}\left( s \right)} \right]\end{equation}$$$$…”

“…The proposed system utilizes the simplest MPPT technique presented in the literature in order to ease the complexity. The P&O type MPPT technique is utilized to obtain the maximum power extraction point [27]. The output of the MPPT technique is V MPPT,PV and the MPPT technique is given below: $$$$\begin{eqnarray*} {V_{MPPT,PV}}\left( n \right) &=& {V_{MPPT,PV}}\left( {n - 1} \right) + d{V_{MPPT,PV}} \\ && \left\{ { \def\eqcellsep{&}\begin{array}{@{}*{1}{c}@{}} {if,d{P_{PV}} > 0andd{V_{MPPT,PV}} > 0}\\ {or,d{P_{PV}} < 0andd{V_{MPPT,PV}} < 0} \end{array} } \right.$$…”

“…Many topologies such as DFSE [24], cascading of two SOGIs as in‐loop filters or pre‐filters [25], were proposed to mend these deficits, but still problem of lower order harmonics and slow response persisted. In order to mitigate these problems, a new topology based on [19], was presented in [26] as mixed multi‐level second and third order generalized integrator (MMLSTOGI) and was modified as multilayer modified quadrature signal generator (MMQSG) in [27]. The presented work further extends the effectiveness of these topologies by further improving the response speed and precision of the extracted fundamental components and termed as multi‐level cascaded dual double fundamental signal extractor (MCDDFSE).…”