Application of Direct Actuated Digital Servo Valve in Electrohydraulic Static Loading System

2011 ◽  
Vol 130-134 ◽  
pp. 4098-4101
Author(s):  
Fa Ming Zhu ◽  
Sheng Li
Keyword(s):  
Control System ◽  
Static Loading ◽  
High Reliability ◽  
Fast Response ◽  
Static Characteristic ◽  
Large Power ◽  
Servo Valve ◽  
Static Testing ◽  
Loading System ◽  
Important Means

Structure static testing is an important means to study the static characteristic of complex engineering structure. Electrohydraulic stactic loading system is the singnificant equipment of the testing. With its function of transfering low-power electrical singal to large-power hydraulic output quickly and precisely, the servo valve plays a key role in an electrohydraulic servo control system and dominates to a large extent the performance of the whole control system. Conventional electrohydraulic servo or proportional control is subject to the nonlinearites of their electro-mechanical interface, such as hysteresis, saturation and finite resolution. In this paper, a direct actuated digital servo valve was applied in electrohydraulic static loading system. It can be driven directly by computer needn’t D/A and has the advantages of simple structure, high tolerance to contamination and high reliability. Practical load-experiment results show that the static loading system with a direct actuated digital servo valve can work steadily and reliably and possess high accuracy and fast response.

A High Flow Rate and Fast Response Electrohydraulic Servo Valve Based on a New Spiral Groove Hydraulic Pilot Stage

2015 ◽  
Vol 137 (6) ◽  
Author(s):  
Shuai Wu ◽  
Zongxia Jiao ◽  
Liang Yan ◽  
Wenhao Dong
Keyword(s):  
Flow Rate ◽  
High Reliability ◽  
Full Range ◽  
Fast Response ◽  
High Flow ◽  
High Flow Rate ◽  
Design Parameters ◽  
Phase Lag ◽  
Servo Valve ◽  
Hydraulic Servo

High flow rate electrohydraulic servo valve is widely applied in hydraulic servo systems. Typical high flow rate servo valve is three-stage nozzle flapper pilot structure which is complicated, unreliable, and highly costly. This study proposed a new two-stage structure high flow rate and quick response electrohydraulic spiral pilot servo valve (ESPV) using a novel hydraulic full bridge spiral pilot stage (FBSPS) as hydraulic amplifier. Its structure is simpler than traditional servo valve which could increase reliability. A design parameters optimization method for servo valve is proposed. It is using an optimization objective function which can balance dynamic performance, static performance, and pilot state efficiency for different design objectives. The particle swarm optimization (PSO) method was applied to get the best key design parameters of ESPV. A research prototype was developed based on the optimized parameters for fast response. The experimental results indicated that the frequency bandwidth (−3 dB amplitude attenuation and −90 deg phase lag) of the ESPV is up to 150 Hz at 20% of full range. This frequency response performance is competitive with existing servo valves, and the simpler structure can improve reliability and reduce cost. Thus, it may have great potential in hydraulic servo system with high reliability requirement, such as aircraft hydraulic servo control system.

The Performance Testing System of Force Motor Valve

2014 ◽  
Vol 635-637 ◽  
pp. 1382-1385
Author(s):  
Dong Dong Chen ◽  
Kun Peng Jiang ◽  
Da Wei Jiang ◽  
Chao Jun Yang ◽  
Min Chen
Keyword(s):  
Performance Index ◽  
Performance Test ◽  
Characteristic Curve ◽  
Steel Production ◽  
Performance Testing ◽  
Fast Response ◽  
Test System ◽  
Static Characteristic ◽  
Servo Valve ◽  
Testing Method

Hitachi force motor valve has been widely used in the hydraulic automatic gauge control (AGC) system of rolling mill due to the characteristics of fast response, high control accuracy and strong anti-pollution ability. It is an important part to control the steel production cost by detecting the performance index of the FMV effectively and in real time. Traditional Servo valve test system detects its static characteristics through the flow and pressure changes between the traffic cavity, and this principle can solve the three position four way servo valve performance test. However, FMV is a special three-way valve and it is hard to test its static characteristic curve like three position four way servo valve. This paper proposes a FMV testing method and has realized it. The test platform is designed and built according to the hydraulic valve testing performance index for detecting the performance of a force motor valve. Not only were force motor valve (FMV) performance characteristics tested effectively but also the performance curves were drawn. The results show that the FMV performance testing method we have built can be effectively used to detect the static performance index of FMV.

Direct Current Deadbeat Predictive Controller for BLDC Motor Using Single DC-Link Current Sensor

2020 ◽  
Vol 38 (8A) ◽  
pp. 1187-1199
Author(s):  
Qaed M. Ali ◽  
Mohammed M. Ezzalden
Keyword(s):  
Control System ◽  
High Speed ◽  
Fast Response ◽  
Bldc Motor ◽  
Current Controller ◽  
Three Phase ◽  
Predictive Controller ◽  
Two Phases ◽  
Dc Current ◽  
Three Phase Inverter

BLDC motors are characterized by electronic commutation, which is performed by using an electric three-phase inverter. The direct control system of the BLDC motor consists of double loops; including the inner-loop for current regulating and outer-loop for speed control. The operation of the current controller requires feedback of motor currents; the conventional current controller uses two current sensors on the ac side of the inverter to measure the currents of two phases, while the third current would be accordingly calculated. These two sensors should have the same characteristics, to achieve balanced current measurements. It should be noted that the sensitivity of these sensors changes with time. In the case of one sensor fails, both of them must be replaced. To overcome this problem, it is preferable to use one sensor instead of two. The proposed control system is based on a deadbeat predictive controller, which is used to regulate the DC current of the BLDC motor. Such a controller can be considered as digital controller mode, which has fast response, high precision and can be easily implemented with microprocessor. The proposed control system has been simulated using Matlab software, and the system is tested at a different operating condition such as low speed and high speed.

scholarly journals Research on an Improved Sliding Mode Sensorless Six-Phase PMSM Control Strategy Based on ESO

Electronics ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1292
Author(s):  
Hanying Gao ◽  
Guoqiang Zhang ◽  
Wenxue Wang ◽  
Xuechen Liu
Keyword(s):  
Control System ◽  
Control Strategy ◽  
Sliding Mode ◽  
High Reliability ◽  
Permanent Magnet Synchronous Motor ◽  
Torque Ripple ◽  
Estimation Accuracy ◽  
Switching Function ◽  
Motor Speed ◽  
Rotor Position

The six-phase motor control system has low torque ripple, low harmonic content, and high reliability; therefore, it is suitable for electric vehicles, aerospace, and other applications requiring high power output and reliability. This study presents a superior sensorless control system for a six-phase permanent magnet synchronous motor (PMSM). The mathematical model of a PMSM in a stationary coordinate system is presented. The information of motor speed and position is obtained by using a sliding mode observer (SMO). As torque ripple and harmonic components affect the back electromotive force (BEMF) estimated value through the traditional SMO, the function of the frequency-variable tracker of the stator current (FVTSC) is used instead of the traditional switching function. By improving the SMO method, the BEMF is estimated independently, and its precision is maintained under startup or variable-speed states. In order to improve the estimation accuracy and resistance ability of the observer, the rotor position error was taken as the disturbance term, and the third-order extended state observer (ESO) was constructed to estimate the rotational speed and rotor position through the motor mechanical motion equation. Finally, the effectiveness of the method is verified by simulation and experiment results. The proposed control strategy can effectively improve the dynamic and static performance of PMSM.

scholarly journals A Full-Range Flexible and Printed Humidity Sensor Based on a Solution-Processed P(VDF-TrFE)/Graphene-Flower Composite

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1915
Author(s):  
Shenawar Ali Khan ◽  
Muhammad Saqib ◽  
Muhammad Muqeet Rehman ◽  
Hafiz Mohammad Mutee Ur Rehman ◽  
Sheik Abdur Rahman ◽  
...  
Keyword(s):  
Active Layer ◽  
Humidity Sensor ◽  
High Reliability ◽  
Full Range ◽  
High Sensitivity ◽  
Fast Response ◽  
Considerable Change ◽  
Relative Humidity Range ◽  
Response And Recovery ◽  
Proportional Relationship

A novel composite based on a polymer (P(VDF-TrFE)) and a two-dimensional material (graphene flower) was proposed as the active layer of an interdigitated electrode (IDEs) based humidity sensor. Silver (Ag) IDEs were screen printed on a flexible polyethylene terephthalate (PET) substrate followed by spin coating the active layer of P(VDF-TrFE)/graphene flower on its surface. It was observed that this sensor responds to a wide relative humidity range (RH%) of 8–98% with a fast response and recovery time of 0.8 s and 2.5 s for the capacitance, respectively. The fabricated sensor displayed an inversely proportional response between capacitance and RH%, while a directly proportional relationship was observed between its impedance and RH%. P(VDF-TrFE)/graphene flower-based flexible humidity sensor exhibited high sensitivity with an average change of capacitance as 0.0558 pF/RH%. Stability of obtained results was monitored for two weeks without any considerable change in the original values, signifying its high reliability. Various chemical, morphological, and electrical characterizations were performed to comprehensively study the humidity-sensing behavior of this advanced composite. The fabricated sensor was successfully used for the applications of health monitoring and measuring the water content in the environment.

Application of PID in Controllable Pitch Propeller of a Multipurpose Ocean Tug

2013 ◽  
Vol 464 ◽  
pp. 253-257
Author(s):  
Hui Fang Chen
Keyword(s):  
Control System ◽  
Automatic Control ◽  
Automatic Control System ◽  
High Reliability ◽  
Control Process ◽  
Good Control ◽  
Control Performance ◽  
Hardware Configuration ◽  
Design Idea ◽  
And Control

This paper takes the automatic control system of controllable pitch propeller in a multipurpose ocean tug as an example to describe the application of the S7-200 series PLC in the control system of 4500 horse power controllable pitch propeller in detail. The principle of control system is addressed, as well as the hardware configuration, the design idea of the main software and control process. The system shows high reliability, accuracy and good control performance in practical in practical running.

Application of Fuzzy Predictive Control in Grain Drying Coal Burning Hot Air Furnace Temperature Control System

2014 ◽  
Vol 530-531 ◽  
pp. 981-984
Author(s):  
Yao Wu Tang ◽  
Xiang Liu
Keyword(s):  
Control System ◽  
Predictive Control ◽  
Fast Response ◽  
Delay System ◽  
Temperature Control System ◽  
Large Delay ◽  
Blast Stove ◽  
Grain Drying ◽  
Hot Blast ◽  
Fuzzy Predictive Control

Grain drying with chain coalfired hot blast stove for temperature stable and economic operation.Boiler control objects with strong coupling, large delay, large inertia characteristics.Fuzzy control on object for low, fast response and predict advanced features. Design the fuzzy predictive controller for chain coalfired hot blast stove temperature control.The test results show that the fuzzy predictive control system is improved effectively the static precision and dynamic characteristic.Fuzzy predictive control for large delay system has better practicability.

Second Paper: Failure-Survival Automatic Flight Control Systems for Aircraft with Particular Reference to a High Reliability Electrohydraulic Actuator

1965 ◽  
Vol 180 (1) ◽  
pp. 246-259
Author(s):  
R. Ruggles
Keyword(s):  
Control System ◽  
Control Systems ◽  
Flight Control ◽  
High Reliability ◽  
Supply System ◽  
Design Criteria ◽  
Flight Control System ◽  
Advantages And Disadvantages ◽  
System Configurations ◽  
Very High

The author discusses some of the problems of failure-survival automatic flight control systems and suggests some basic ground rules as design criteria. The advantages and disadvantages of some of the main types of system are discussed: duplex, triplex, triple component, duplicate-monitored and quadruplex systems being covered. In particular, a quadruplex actuator is described which has been designed and developed mainly for automatic flight control system applications where a very high degrees of failure-survival capability is required. A detailed failure analysis of the various systems is carried out and the importance of the electrical and hydraulic supply system configurations and failure rates is brought out.

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