Abstract: Reactive power compensation technology? plays a vital role in ensuring power quality and supply reliability. To address issues such as frequent switching of capa-citors and poor sta-bility of electrolytic capacitors in traditional compensation methods, an elec-trolytic capacitor-free reactive power compensation method based on a cycloconverter is intro-duced. This meth-od dynamically compensates for reactive power by adjusting the duty cycle.??? Furthermore, to tackle the difficulty of parameter tuning in closed-loop control systems, the ch-icken swarm op-timization algorithm is applied to design an improved PI controller for dynamic regulation. Si-mulation results demonstrate that the proposed method simplifies parameter tuni-ng and enables the static var compensator to rapidly achieve reactive power balance.