In response to the requirements of helicopter payloads, multiple turboshaft engines are installed and run in parallel. Ideally, when all engines are functioning normally, they should share the load equally. This ensures that in the event of sudden disturbances or during transitional operating conditions, all engines can respond almost identically to changing disturbances. Equal torque output also helps extend the service life of the helicopter’s transmission system. This paper investigates the redundancy design method for digital electronic controllers of turboshaft engines under a “multi-rotor-dual-redundancy” architecture. It proposes a system logic architecture and physical architecture, designs and implements fault logic, channel switching, data flow fault tolerance, and synchronization for dual-redundancy channels, while also addressing redundancy control and matching under multi-rotor configurations. This method can be widely applied to the development of digital electronic controllers for turbojet, turbofan, and turboprop engines.