Taking into account the high rotor speed of the generator and the trend of high
voltage in direct current microgrids in high-power aviation hybrid propulsion
systems, a hybrid power system with a power of 200 kilowatts (kW), a voltage of
540 volts (V), and a rated generator speed of 10500 r/min was established.
Anticipating the demands of future high-power system tests, a matching
simulation model was developed. The paper discusses various aspects including
model construction, test design, and result validation, proposing an overall
control strategy for series hybrid aviation propulsion systems – utilizing
lithium-ion batteries to stabilize grid voltage and using the
turboshaft-generator unit as the primary power source to meet the main power
demands of the electric propulsion system. The established model consists of
four modules: turboshaft engine, power generator, voltage-stabilizing battery,
and electric motor/propeller. These modules are independently controlled and are
unified into a microgrid through a direct current bus. In the designed cases,
the simulation data including generator speed, gas turbine speed, grid voltage,
and component power were compared and analyzed against experimental data. The
results indicate that both steady-state and dynamic errors of the simulation are
controlled within 10%. This implies that the constructed simulation model
accurately replicates the operational state of the 200 kW-level series hybrid
aviation propulsion system. It serves as a pre-research platform for testing
system control strategies and developing new control algorithms. Finally, the
feasibility of a strategy to appropriately increase the power of the
turboshaft-generator set and maintain battery output power fluctuations within 0
kW was validated within the simulation system, providing a reference for future
experiments.