Investigation on positioning control strategy and switching optimization of an equal coded digital valve system
| Autor: | Matti Linjama, Gao Qiang, Yuchuan Zhu, Miika Paloniitty |
|---|---|
| Přispěvatelé: | Tampere University, Automation Technology and Mechanical Engineering, Research group: Innovative Hydraulic Automation |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
0209 industrial biotechnology
Computer science Mechanical Engineering 213 Electronic automation and communications engineering electronics 020208 electrical & electronic engineering Control (management) 02 engineering and technology Circular buffer 020901 industrial engineering & automation Control and Systems Engineering Modulation 0202 electrical engineering electronic engineering information engineering Electronic engineering Pulse number |
| Popis: | This article concerns high accuracy positioning control with switching optimization for an equal coded digital valve system. Typically, pulse number modulation control cannot realize micro-positioning due to the characteristics of step-wise flow variation, therefore, a new position controller consisting of a model-based pulse number modulation and a differential pulse width modulation strategy is proposed to control the position of a hydraulic cylinder at high and low velocity cases, respectively. In addition, in order to solve several problems caused by the pulse number modulation and differential pulse width modulation, such as increased number of switchings and large difference among number of switchings of valves, a switching optimization consisting of a switching cost function, a circular buffer and a circular switching method is proposed. An adaptive weight of the switching cost function is proposed for the first time to reduce the total number of switchings under different pressure differences and its design criterion is presented. A circular buffer and a new circular switching method are used to improve the degree of equal distribution of switchings when the pulse number modulation and differential pulse width modulation are used, respectively. Comparative experimental results indicated that the average and the minimum positioning error for the proposed controller are only 10 and 1 μm, respectively. The number of switchings and the degree of equal distribution of switchings are significantly optimized. Moreover, the pressure fluctuations caused by the proposed controller remain acceptable. acceptedVersion |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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