As one of the most promising approaches for reducing automotive fuel consumption, hybrid powertrain has inspired extensive research efforts on system control and energy optimization. However, the time and cost of constructing or modifying a physical hybrid powertrain seriously affects the experimental investigation of the complicated system dynamics, so as to limit the development of the precise hybrid powertrain control and optimization. To provide an accurate and flexible hybrid powertrain emulation tool for developing the hybrid control methodologies, a rapid prototyping hybrid powertrain research platform, which employs a transient hydrostatic dynamometer to emulate the dynamics of various hybrid power sources and different hybrid architectures, is constructed. In this research platform, a three-level closed-loop control system is designed for realizing the hybrid powertrain emulation. With respect to the high/middle/low level systems, a suite of hybrid powertrain controllers including an adaptive driver model, an energy optimization strategy, a virtual hybrid torque controller and a dynamometer torque controller are designed and, further, their interactions are analyzed. Experimental results demonstrate that the proposed control system can achieve the precise emulation of the typical hybrid powertrain operation. © 2011 AACC American Automatic Control Council.