Citation Context

...r, a smaller perturbation size slows down the MPPT. A solution to this conflicting situation is to have a variable perturbation size that gets smaller towards the MPP as shown in [8], [12], [15], and =-=[22]-=-. In [24], fuzzy logic control is used to optimize the magnitude of the next perturbation. In [20], a two-stage algorithm is proposed that offers faster tracking in the first stage Fig. 3. Divergence ...

Citation Context

...tics on solar insolation and temperature. As these parameters vary continuously, MPP also varies. Considering the high initial capital cost of a PV source and its low energy conversion efficiency, it is imperative to operate the PV source at MPP so that maximum power can be extracted. In general, a PV source is operated in conjunction with a dc–dc power converter, whose duty cycle is modulated in order to track the instantaneous MPP of the PV source. Several tracking schemes have been proposed [2]–[12]. Among the popular tracking schemes are the perturb and observe (P&O) or hill climbing [4], [5], incremental conductance [8], shortcircuit current [2], open-circuit voltage [7], and ripple correlation approaches [6]. Some modified techniques have also been proposed, with the objective of minimizing the hardware or improving the performance [7], [9]–[12]. The tracking schemes mentioned above are effective and time tested under uniform solar insolation, where the P–V curve of a PV module exhibits only one MPP for a given temperature and insolation. Bruendlinger et al. have tested various commercially available inverters in partially shaded conditions and have found that the power loss due...

Citation Context

...ld Values A theoretical analysis regarding the optimal choice of the main parameters (sampling frequency and perturbation size) of the P&O method, which is also valid for the dP -P&O, can be found in =-=[16]-=-. The threshold ThP has been chosen to be zero. This is because if the last perturbation had a positive effect on the output power, regardless of the size of the change, the MPPT should continue the p...

Citation Context

...al user-dependent constants for the perturb adaptation [38], [39]. Novel techniques show improved performance using nonlinear equations [41], fuzzy logic [42], and complicated optimization algorithms =-=[43]-=-, [44], yet not common due to their complexity and need of sophisticated controllers [5]–[7]. In this paper, an innovative P&O technique is presented. The proposed technique utilizes the rate of chang...

Citation Context

... [12]. The hill-climbing method directly computes the MPP by measuring the gradient of the output power in dependence of the output voltage [13]. A similar technique, namely, perturb and observe [6], =-=[14]-=-, continuously perturbs the systems in order to detect the MPP, and the operating voltage of the panel oscillates around it. The incremental conductance method [15] is based on the fact that the slope...

Citation Context

...rized by the duty cycle control. In the literature, it is known as Hill Climbing (HC) or direct control method. As the latter name implies, HC operates by directly updating the converter’s duty cycle =-=[16]-=-. The approach greatly simplifies the control structure as it eliminates the need for the proportional integral (PI) or hysteresis controller. In principle, it works on the same concept as P&O, but in...

Citation Context

...dinatespower provisioning control and load matching. Our techniquesenables joint optimization of solar energy utilization andsworkload performance.sMany algorithms have been proposed for MPP trackings=-=[3, 29, 32]-=-. A detailed comparison between different MPPstracking methods can be found in [33]. Different approachessof modeling a PV panel is discussed in [8, 9]. In this paper,swe show that the multi-core syst...