Impact of non-deterministic software execution times in SmartGrid applications

Electricity companies will only allow customers to inject power into the grid network if the customer’s system is in synch with both frequency and phase as the grid itself. This is normally achieved using a specialised machine sold by the energy provider. It may be possible to achieve this via low cost, low power nodes such as a Raspberry Pi, to synchronize frequency and phase as well as voltage and current. In order to synchronize to microsecond or nanosecond precision, the hardware being deployed must in itself be able to achieve said precision when coupled with software. In this paper we evaluate the level of nondeterministic execution times in two versions of a widespread embedded compute platform, namely Raspberry Pi.