Proposed by [PERSON] in 2008, the FA [27; 28; 29; 30] mimics the flashing behavior of fireflies. In nature, fireflies are attracted to each other by blinking signals. The more brightly a firefly glows, the more fireflies it attracts. Particularly, fireflies are randomly attracted to different light sources with the same intensity. Consequently, the brightest firefly is the optimal solution. The FA requires a smaller number of parameters and provides a wide search scope, fast convergence and high stability, while being very likely to get trapped in a local optimum solution, particularly in a multi-dimensional problem. The variable step size P&O method [31] is considerably sensitive to the initial parameter values, so the performance of its maximum power tracking controller is highly dependent on the selection of initial parameters. Therefore, the parameters must be selected and controlled carefully for this tracking technology, or there would be a significant impact on the tracking performance of its algorithm. Moreover, it is necessary to pay attention to the selection of the sample distribution and the adjustment of the parameters in order to improve the performance of the algorithm and increase the convergence speed. As for the shuffled frog-leaping (SFL) algorithm [32], a large amount of storage space and computing resources are usually required, and the increase in the number of groups will slow down the execution of the algorithm. Even more, insufficient computer memory capacity might be a result. Moreover, more parameters need adjustment while different parameters might need to be used in different application scenarios. Therefore, it becomes more difficult to adjust the parameters of the algorithm. In light of this, this paper presents an improved version of the FA to locate the GMP of a P-V curve with multiple peaks. The improved version is simple and straightforward; the step size in particular is made adaptive to the slope of a P-V characteristic curve. In this manner, it takes the improved version a shorter period of time to get away from a LMPP than the original, and the GMPP can be tracked down more efficiently. Due to advances in power electronics, converters have been widely applied to MPP trackers so as to raise the power generation efficiency of a PV array. However, a major disadvantage of conventional DC-DC converters is the low voltage ratio due to the typical duty cycle [34; 35; 36]. For this sake, a great amount of effort has been put over the years into developing converters with a high voltage ratio. For example, the voltage ratio was raised as intended using coupled inductors with a high turn ratio [37; 38; 39; 40]. Nonetheless, this move increased the output ripple voltage of a converter. Based on the same configuration as in [37; 38; 40], a converter is presented in this work as a solution to the above-referred problem. Inductors were replaced with coupled inductors therein so as to raise the voltage ratio,and clamp capacitors were also used to suppress the output voltage ripples in an effort to improve the performance of the converter. The presented converter was then simulated using PSIM software [41] for performance validation. The organization of this paper is arranged as follows. The working principle of the adopted high boost ratio converter and its component design are described herein in Section 2. Next, the P-V and I-V output characteristics of a PV module under shading are described in Section 3. Subsequently, the working principle of the conventional FA is described, followed by proposing an improved FA, in Section 4. Finally, some simulation tests are performed in Section 5 to verify the effectiveness of the proposed improved FA for MPPT.