The Rankine cycle describes the ideal thermodynamic cycle for a heat engine to produce the best performance and convert heat into mechanical work while it undergoes phase change. Is it possible for us to build an ideal heat engine that conforms as closely as possible to the performance of the ideal Rankin cycle?
By definition, no engine is ever truly ideal (assuming 'ideal' means 'loss-less') as per the law of conservation of energy. No engine will ever operate at 100% efficiency, and further no Carnot engine can operate above ~63.4% efficiency; this is what the Rankine Cycle tells us.
However a 63.4% efficiency is assuming that only the entropy generated by the heating/cooling process itself is taken into account. Once you introduce practical inefficiencies of mechanical systems (imperfect fluids, friction, structural defects) this number decreases rapidly.
Modern gasoline-driven internal combustion engines operate around 30%, diesel engines around 45%, and coal power plants around 40%.
So, assuming by 'ideal' you mean the theoretical maximum of 63.4% then the answer is still no, because no engine will ever be completely devoid of practical inefficiencies.
To put it a bit more scientifically...
As the practical inefficiency of an engine approaches zero, the absolute efficiency of a Carnot engine approaches 63.4%.
Because a real Carnot engine will never have a practical inefficiency equal to zero, the absolute efficiency will never be equal to 63.4%