Peak current control based maximum power point trackers for faster transient responses

The perturbation and observation (P&Q) maximum power point tracking (MPPT) algorithms are very common in PV systems. Implementations of P&O algorithms based on peak current. control and on instantaneous sampled values have shown to provide very fast transients and small oscillations around the maximum power point (MPP). However, operation with fixed variation of the reference current results in a trade-off between speed of response and maximum power yield in the steady state. Variable variation of the reference current can be successfully done with Fuzzy logic but results in significant computation burden for common digital signal processors (DSP). Thus the minimum time step is relatively large what reduces the transient response of the scheme. This paper presents an alternative approach based on non-switching zones and compares by simulation the performance and discusses the implementation difficulties of 4 peak-current controlled P&O APPT algorithms.