"at a preliminary level" is correct and usable in written English.
It can be used to indicate that something is at an early, initial, or introductory stage. For example, "At a preliminary level, this research suggests that further study is necessary."
Currently, the APF, STATCOM, UPQC based on MMC have been discussed at a preliminary level [18, 19, 20].
Such multi-band scheme was already proposed earlier by the authors at a preliminary level, and is here developed further toward flexible and reconfigurable A/D interface for cognitive radio (CR) receivers enabling efficient parallel reception of multiple noncontiguous frequency slices.
Furthermore, despite the fact that the proposed methodology is validated at a preliminary level, focusing on the recovery of a single component from an aqueous solution, it could be served as the first step for the development of a more realistic model to predict the behaviour of a multi-component system.
The context of Phase 2 and the issue to be tackled in this phase are briefly described; since this phase has been carried out only at a preliminary level (mainly after the end of the project), the results obtained are not reported here in detail but are only briefly commented on.
In a sign of the anxieties still gnawing at households, the University of Michigan Consumer Sentiment Index this month plunged to a preliminary level of 69.5 compared with 73.6 in March.
It is used to depict facets of the decision making strategy and rationale of an adaptive system at the preliminary level of requirements.
so far, the increasing interest on this polysaccharide significantly aroused the alternative search from marine sources since it is at the preliminary level.
Generally, data on the acute, sub-acute and chronic toxicity of nanoparticles used in nanomedicine has begun, but they are still at preliminary level and patchy [13].
