Papers by Author: Guang Lin Wang

Abstract: Passive torque servo system (PTSS) is a key equipment in the hardware-in-the-loop experiment for the test of actuator performance. A novel mathematical model was obtained by analyzing the structure and working conditions of PTSS in this paper and the model was analyzed with the matlab software. PID controller was used to correct the actuator system and the result is effective. The disturbance torque was analyzed on different frequency of command signal, it was found that the disturbance torque increases, and with the phase ahead of the signal, but the amount of lead decreases with variation of frequency of command signal. Three components of the disturbance torque were obtained by theoretical analysis, and the reverse current compensation method was composed. It was found that the proportion of three parts of disturbance torque changed with increasing frequency of command signal and the reason of the variation was analyzed. Finally, the theoretical analysis of the construction of disturbance torque was correct by the comparison of the result of simulation.

Abstract: HLP type hydraulic oil has wide application in aerospace field. The existing measurement method of Laval nozzle throat diameter efficiency is low, and has the potential to cut parts surface. Therefore, a non-contact throat diameter measuring method based on the hydraulic oil is proposed. Then the flow field is simulated, and measurement parameters are calculated. The flow field analysis results show that this method is suitable for measuring Laval nozzle throat diameter.

Abstract: Pressure type pneumatic measuring is the most wildly used method in overlap value testing, which depends strongly on the constant pressure of gas supplying. However,control of pressureisrarely done before.This paper presentsa design of a new overlap value measuring system with pressure control sub-system, mechanical platformand a program-controlled sub-system. A hybrid controller is developed combined with fuzzyself-adjusting PID and time-optimal control. The final version of this controller is a computationally efficient analytic scheme suitable for implementation in thereal-time closed-loop pressure digitalcontrol. At last, the system control software developed on LabVIEW is briefly introduced.

Abstract: Torque motor is the electrical - mechanical converter of servo valve, is the bridge connecting electrical devices and hydraulic devices, is one of the key elements of electro-hydraulic servo valve. The main object of study of this paper is moving iron permanent magnet torque motor. The dynamic characteristics of torque motor are the key parameter to measure the overall performance. At present, the research of most of manufacturers emphasize on the test of integral valve servo valve. Torque motor is also designed to mimic the structure and size of foreign-based valve, lacking of system understanding for characteristics of servo valve. Early in the design, people cannot effectively control the overall performance of the torque motor products. There is large performance difference with a larger group of torque motor, producing serious waste. This paper describes the principle of dynamic characteristics test, establishes a test system of dynamic characteristics for torque motor, accurately obtain nature frequency and bandwidth of torque motor on the test bench which we have established before.

Abstract: This article analyzes the deviation of existing stiffness measurement method and comes to the main components of the measurement error. Focus on the influence of the bending deformation all of aspects and contact deformation between the various links to the measurement accuracy. Establish the relationship between the actual deformation and the measured deformation to the spring tube through homogeneous coordinate transformation and finite element analysis, in order to identify the error sources impact on the measurement greatest, and improve the measure methods to against the main error source, eliminate the influence of the main error source to the stiffness measurement, then achieve the purpose of improving the measure accuracy.

Abstract: Electrical energy directly converted into mechanical energy of linear motion by linear force motor, greatly enhancedthe rapid response ability and control precision of the feed system. The product quality of linear force motor can be effectively improved by design a performance test system of linear force motor. The paper designed a performance test system of linear force motor based on the Labview virtual instrument platform, and test project of linear force motor has been planned, the test method, the structure of the test device, power drive module, step motor load part, data acquisition and the software system all have been completed. The test system realized automatic and manual two different kinds of test methods, data acquisition and management and processing function and the good human-machine interface, the linear force motor dynamic and static parameter, including input current, output force and output displacement and the relationships between them have been tested.

Abstract: This article describes the elastic element of the servo valve, elaborates the definition of the stiffness of elastic element, analyzes the characteristics of existing rigidity measurement system, points out the limitations of the existing rigidity measurement system when it measures the large-stiffiness elastic element, utilizes a new measuring principle based on the existing stiffness test systems, uses the more accurate laser displacement measurement method to overcome the weaknesses of the existing stiffness test system, improves the measurement accuracy, makes stiffness measurements more accurate and promotes the stiffness measurement technology of the servo valve elastic element.

Abstract: Torque motor is an electrical-mechanical converter of servo valve, is bridge which connects the electrical devices and hydraulic devices, is one of key components of servo valve. The permanent magnet torque motor is studied in this paper. As key parameters of design of servo valve, the magnetic property of torque motor determines magnitude of the electromagnetic torque. At present, many manufactures of servo valve pays more attention on the test of integral servo valve. The design of torque motor also bases on experience, lacking of specialized tool for torque motor test. This paper described the principle of magnetic property of the test, developed a test system for magnetic characteristics, and established the relationship between the electromagnetic torque and current control current, and the relationship between output angular displacement and control current.

Abstract: Dual inverter fed open-end winding induction motor (OEW-IM) is a new solution for multilevel drive. Comparing with traditional multilevel converters, the dual inverter is being interested in for its more flexible current control, the absence of fluctuating neutral point, and fault-tolerant capability. This paper analyzes the potential common-mode voltage (CMV) in the open-end winding induction motor system, and proposes a new space vector PWM (SVPWM) strategy to reduce the CMV. The proposed method is validated by simulations and experiments.

Abstract: The disturbance torque which is caused by the interference of the motor position has observably impact on accuracy of the loading system. According to unstable loading channel and disturbance torque, this paper use a complex control algorithm of differential forward PID control and feed-forward compensation. At the end of this paper, the simulation analysis results show that the feed-forward compensation can observably eliminate the influence of the disturbance torque, and improve the accuracy of the loading system.