This study investigates the frequency control of an isolated hybrid power system (HPS) in the presence of parabolictrough solar thermal power system (STPS), wind generator, diesel engine generator and battery energy storage system to ensure the system reliability. Dynamic performance of the HPS has been analysed considering the degree of penetration of solar thermal power. The inclusion of parabolic-trough-based STPS in such study is a maiden work. For coordinated control of the whole system and to damp out the oscillations occurring due to the disturbances, proportional-integral (PI) and PIderivative controllers are incorporated whose gain parameters are simultaneously optimised by genetic algorithm, particle swarm optimisation, and mine blast algorithm (MBA). MBA-based control strategy in such a hybrid system has been reported for the first time. The dynamic response analysis with different algorithms figured out that the parameters of controllers tuned by MBA provide a significant improvement in the performance of HPS.