Multi-terminal, radial and meshed high voltage direct current (MT-HVDC) transmission is considered to be a promising technology for transmission of energy from renewable sources. One of the key components of HVDC grids currently under intensive research is the HVDC circuit breaker (CB). A few industrial concepts of HVDC CBs, especially as a result of advances in power electronics, have been proposed and prototypes have been built. However, performance verification of these breakers under realistic operating conditions equivalent to the actual and foreseen HVDC grids has not been demonstrated. Since these tests require high power DC sources which are not available yet, special test circuits must be considered. Hence, in this paper, various possible circuits for testing HVDC CBs are investigated. A novel method of testing an HVDC CB using reduced power frequency AC short circuit generators, imposing adequate stresses as expected in service, is proposed and practically implemented in a high power laboratory. The oscillograms of prospective current and voltage obtained in an experimental test circuit sufficiently agree with simulation results. An active current injection type HVDC CB is modelled and inserted into simulated test circuits. Comparison of the resulting stresses with ideal and more or less practical DC circuits provides insight into the future test requirements of the HVDC CBs.