Transient characteristics of in-depth study of optical voltage transformer, in order to ensure the correct operation of protection relay of automation equipment, in order to promote the application of new protection principle.. Based on the theoretical analysis of optical voltage transformer mathematical sensing model, established a set of transient simulation system. To explore the short circuit at different angles and with trapped charges of reclosing transient process, factors related to optical voltage transformer transient characteristics and effects. Established a set of optical voltage transformer transient characteristic test system, including hardware platform and application software. Tested the actual optical voltage transformer transient characteristics, provides a set of practical detection method for engineering application of optical voltage transformer.