Research on Evaluation Method of Safety Integrity for Safety-Related Electric Control System of Amusement Ride

The safety-related electric control system (SRECS) of amusement ride as an important system ensures the safe operation of the device. Its safety integrity determines whether the SRECS can perform safety functions reliably. At present, the professional safety integrity evaluation of the SRECS for amusement ride is still blank all over the world. Based on the analysis of the structural type and movement characteristics of the amusement rides, this paper develops a safety integrity evaluation method suitable for the SRECS of amusement rides with reference to the international function safety standards of safety-related system. First step is to identify the safety-related control function (SRCF) of SRECS combined the failure case database, and then to do the risk assessment of SRCF considering the failure severity and possibility, such as death, injury, and high altitude detention. The safety integrity level requirements of ride (RSILr) can be obtained by risk matrix. The four reliability indicators of the designed control loop are analyzed, and the safety integrity level (RSIL) of the control loop is obtained by combining the safety integrity histogram. Finally, the effectiveness of the safety integrity of the control system is confirmed by tests.