Abstract: In response to interference issues affecting partial discharge (PD) detection in complex electromagnetic environments during high-voltage cable accessory installation, four suppression techniques are proposed: improved LMS adaptive filtering for random pulse separation, periodic interference suppression via chaotic systems, narrowband interference removal in combined time–frequency domain, and source control through installation process optimization. A 110kV simulation platform tested 50~200Hz periodic interference, 100~500kHz narrowband interference, and 1~10V random pulse interference, followed by 12 months of on-site monitoring. Results show over 92% attenuation for all interference types, PD signal fidelity above 95%, significant delay in insulation degradation, and stable long-term performance. This study provides technical support for accurate PD detection during cable accessory installation.