Dynamic Control Method of Electric Loading System of Linear Steering Gear

Abstract

The invention discloses a dynamic control method of a linear steering engine electric loading system, comprising the following steps: modeling a servo loading motor, constructing a torque balance equation, and constructing a linear steering engine mechanism model; building a ball screw pair motion model; analyzing the transfer function of the electric loading system, designing a three-closed-loop control method based on a current inner loop, a position outer loop and a force outer loop, and applying complex vector PI control in the current inner loop to enable the current of the servo loading motor to track instruction signals quickly and accurately; and finally, making feed-forward compensation for angular velocity, and verifying the control method. The method takes an electric loading system driven by a permanent magnet synchronous motor as a specific object, and considers the impact of the characteristics of the linear steering engine and the coupling degree between the linear steering engine and the electric loading system. The active force of active displacement of the linear steering engine is inhibited, and the loading precision of the linear loading system is improved. Moreover, a verification method is put forward, which makes a linear load simulator better evaluated.

Description

technical field [0001] The invention belongs to the technical field of control devices, in particular to a dynamic control method for an electric loading system of a linear steering gear. Background technique [0002] In scientific research and industrial production in national defense, aerospace and other fields, it is usually required to test product performance to ensure the performance of the designed product. The electric steering gear is a classic actuator in the aerospace field, which is of great significance to the normal flight and maneuver control of the aircraft. It is an important flight control servo component. As a new type of power transmission actuator, the linear steering gear has Wide application prospects, in addition to being used in the flight control system, it can also be used in other occasions that require action on the aircraft. In the early development process of linear steering gear, the performance test of linear steering gear often required mul...

AI Technical Summary

Problems solved by technology

At present, the linear loading method mostly adopts the swing rod type, mechanical type or elastic rod method. These linear loading methods cannot meet the requirements of automation and intelligence of the load simulator, and their control methods are of little significance.

In the application of large torque loading, the main research is the electro-hydraulic servo loading system with hydraulic motor or actuator as the actuator. Document 1 (CN106055753A) discloses a servo command for the excess force of the electro-hydraulic load simulator. Dynamic compensation control method, this loading method has disadvantages such as oil leakage, inconvenient maintenance, sensitivity to oil pollution, and frequent failures. In addition, nonlinear factors such as large inertia and seal friction also greatly affect the loading accuracy, and from From the point of view of the control method, due to the active movement of the load-carrying system and the large connection stiffness causing strong positional interference to the loading system, forced commutation occurs in the two chambers of the loading hydraulic motor, and the commutation produces forced pressure, which is the cause of the electro-hydraulic passive torque. The main reason for the excess torque of the servo system is that the excess torque is often very large, which seriously affects the loading accuracy, and there are interference factors such as servo valve dead zone and pressure fluctuation in the electro-hydraulic system, and the system parameters are easily affected by changes in ambient temperature and working temperature. Systems with strong nonlinear and time-varying factors

Therefore, due to the influence of nonlinear and time-varying factors on the accuracy of the model coefficients of the electro-hydraulic load simulator, the difficulty and complexity of the controller design of the electro-hydraulic load simulator increase;

[0005] Document 2 (CN106527150A) discloses a nonlinear composite control method of a pneumatic servo loading system, but due to the characteristics of the gas itself such as low stiffness, weak damping and uncertainty of the parameters of the pneumatic system, further research and development of the pneumatic servo control technology are restricted. application, its control method is of little significance;

[0006] Document 3 (CN102141484A) discloses a multifunctional portable electric servo control loading device and its loading method. Its loading mode is only static loading or cyclic loading under force control or displacement control, that is, only "active loading" can be realized , which is equivalent to static loading, without interference factors such as redundant force, but cannot achieve "passive loading" for linear steering gear;

[0007] However, the dynamic control method of the passive load simulator has always been the key direction of research at home and abroad, but the research on the load simulator is mostly applied to the loading test of the rotating steering gear, and most of them focus on the torsion-to-torsion torque loading, while the linear The structure of the linear load simulator is relatively complex, and the excess force caused by the active linear motion of the measured linear servo motor is more difficult to suppress; the linear load simulator driven by the linear servo motor has the limitations of active loading, high cost, and manufacturing problems. The shortcomings such as inconvenient maintenance, etc., cannot load the linear steering gear that is actively moving

In the prior art, there is no research on the control method of the linear steering gear load simulator, especially the dynamic control method applied in a high-precision linear steering gear electric loading system

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