Research on classical field-oriented control w.r.t. to linear feedback control is largely finished. Current research focus is on model predictive control (cf. https://www.wiley.com/en-gb/Model+Predictive+Control+of+High+Power+Converters+and+Industrial+Drives-p-9781119010906) and machine learning-based control (e.g., using reinforcement learning cf. https://ieeexplore.ieee.org/abstract/document/9376968). Both can (but not must) be integrated within a field-oriented coordinate system.