Authors:  James Langston; Andrew Rockhill; Karl Schoder; Michael Sloderbeck; Michael Steurer

Extended Abstract:

An approach for testing the operation and coordination of medium-voltage dc solid state circuit breakers (SSCB) for shipboard power systems is described. For the considered application, the rate of rise of current during a short-circuit is limited primarily by a small cable inductance.  This high rate of rise, coupled with the need to interrupt the current prior to exceeding the limits of the power electronic switches in the SSCBs, necessitates a coordinated protection scheme which can isolate the fault within a matter of microseconds. Challenges in such tests include the high-voltage, high current, high rates of change of current, and the interconnection of devices within a system. Testing of the SSCBs in a system context presents a challenge, as the MVDC system to which these are to be applied has been realized neither in an actual shipboard implementation, nor in a land-based test site. In order to cope with these challenges and verify the operation of the SSCBs within a system context, a combination of tests and analyses are employed, including off-line simulation, controller hardware-in-the-loop simulation, hardware testing of a single SSCB, and coordination testing with multiple SSCBs. Results are described for testing of 1 kV devices, but the approach is developed to allow for extension for devices of higher voltage ratings.

Applying and extending the approaches described in this work, continuing efforts focus on the development and testing of SSCBs for use in medium voltage dc systems. Funded by the US Office of Naval Research (ONR), the team at Eaton continues to develop the pure solid-state CB technology. Funded by the US Department of Energy (ARPA-E) the team at FSU in collaboration with Georgia Tech develops a hybrid CB by pairing an ultra-fast piezo actuated mechanical switch with a novel power electronic circuit. Both projects aim at a prototype for a 12 kV dc system with a continuous current rating of 2kA.

2019 Best conference paper award for IEEE Industrial Electronics Society
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