Nuchkrua, T., and T. Leephakpreeda. “Adaptive PID Control of DC-Link Voltage via DC/DC Buck-Boost Converter”. Science & Technology Asia, vol. 18, no. 2, Oct. 2015, pp. 42-53, https://ph02.tci-thaijo.org/index.php/SciTechAsia/article/view/41147.