Study On The Thrust Quality Evaluation Method Of Solid Attitude And Orbit Control Power System

Attitude and orbit control engine is core parts of kinetic energy interceptor, and the thrust performance of it in terminal guidance directly affects whether the missile could hit the target. The attitude and orbit control valve of anattitude and orbit control engine is kind of a disposable product, whose performance cannot be assessed by gas test. Besides, attitude and orbit controlsystem involves complex mechanism, which composed of several control valves, and always come along with complex multi-component problems. Thus it’s necessary to conduct investigations of assessment methods for thrust quality in solid attitude and orbit power system.The actuation gear of solid attitude and orbit power system is attitude and orbit control valve, of which the performance evaluation requires a thrust testing system. In this paper we developed detailed analysis for the four-component thrust test system used in our test experiments. In order to evaluate the static indicator of thrust quality in an attitude and orbit control engine accurately, we carried out researches for assessment methods of interference force in cooling pipe, nozzle throat leakage in attitude and orbit control valve, and leakage in exhaust vent by means of theoretical analysis. The results indicate that because the four-component thrust test system employs piezoelectric structure, it has good dynamic performance and stiffness. However, the static accuracy is comparatively low and only suitable for measurement of high-frequency signals. When measuring static signals for a long time, there’re interferences to testing results due to charge leakage, which requires subsequent compensating processing. Through the investigation of assessment methods for interference force in an attitude and orbit control system, we provided basis for improvements of attitude and orbit control valve, and facilitated subsequent studies of cool air and hot gas tests.In order to evaluate the dynamic indicators of thrust quality in an attitude and orbit control engine precisely, we employed strike method and modal test to obtain the dynamic performance indicator of thrust test bench, and also employed bi-modal damping compensation method and simulation optimization to improve the dynamic performance of thrust test bench. The results indicate that tapping on a bench together with simulations to get the damping ratio and vibration frequency of the bench is a reasonable way to obtain the dynamic performance indicator. Bi-modal damping compensation method could satisfy the requirements of dynamic thrust testing, and the test system after compensation has good dynamic performance. It can be inferred from our simulated analysis that the intrinsic frequency of dynamic components can be improved effectively by optimizing structures of moving frames and measuring shaft. Besides, the application of smaller pre-tightening force also benefits the dynamic performance of thrust test bench.Finally we investigated problems through both cool air and hot gas experiments, focusing on issues about thrust consistency in attitude and orbit control valves and thrust correlation between cool air and hot gas conditions. The results show that we can evaluate the performance of control valves by cool air tests and the assessment results can provide support for improvements and acceptance inspection of valve structures.