Abstract: Introduction When a transformer is in light load or no-load, the excitation characteristic of the transformer and other comprehensive reasons usually produce large inrush current and cause trip accident. Excessive inrush current may cause damage to transformer internal winding and short service life. Common suppression inrush current technology in the application of three-phase interconnected circuit breaker has certain limitations, therefore, it is urgent to solve this problem in engineering applications. Method This article applied a specialized device which is based on the theory that the magnetic biasing opposites the remanence. After updating a three-phase interconnected circuit breaker's control circuit, this article carried on a no-load test. Result The result demonstrates that this technology can suppress inrush current in the control of three-phase interconnected circuit breaker, and the suppression effect is good. Conclusion This technology is stable and effective and can be promoted in practical projects.