An operation algorithm for the combined thrust vector control system of a rocket engine

Abstract

The new combined rocket engine (RE) control system consists of combining various control systems - mechanical thrust vector control system (MTVCS) and gas-dynamic one (GDTVCS) within one bifunctional system that performs the functions of controlling and stabilizing the rocket stage flight. Previously it was shown that the MTVCS speed has limit, since with its speed increase the sensitivity to high-frequency random disturbances rises, which increases random errors. In addition, the system performance rise leads to an increase in the mass and dimensions of the steering drive of the engine swing. As part of the combined system, GDTVCS supplies any given speed requirements, and MTVCS provides maximum control efforts with minimum drive power and maximum element simplicity of the thrust vector control system as a whole. However, there is a problem of rational function distribution between subsystems and coordination of their functioning. For automatic control of the RE thrust vector, the input data are angle deviations in a certain plane, which characterize the direction violations of the installation.The purpose of the work is to study the input signal characteristics of the thrust vector system of steering engines applied to the combined RE control system and the design of an optimal algorithm for its operation.There were analyzed possible determining methods for the trend existence of the input signal on the characteristic RE operation intervals and method was proposed for selected trend using. This made it possible to develop an algorithm for the functioning of the combined (mechanical and gas-dynamic) thrust vector control system of the rocket engine. The created algorithm provides the processing of the TVCS input signal with the selection of the deterministic (static) component (trend) and high-frequency signal oscillations (deviations from the trend). The trend type of the deviation angle perturbation of the RE thrust vector is also taken into account. The typical dependence of the output control actions for the steering RE on the input signals at different operation time intervals is investigated.The developed algorithm allows optimal separating (in terms of energy consumption for creating control efforts) the subsystem functions of the combined RE thrust vector control system, to improve the quality and reliability of the flight control system of the rocket stage.