Research on Pressure Control of an Electro-Hydraulic Servo System Based on Sliding-Mode Variable-Structure Direct Torque Control
Round 1
Reviewer 1 Report
Review Report for
Research on Pressure Control of an Electro-hydraulic Servo System Based on Sliding-Mode Variable-Structure Direct Torque Control
In this paper, in order to solve the problem of high-precision pressure control in DDVC electro-hydraulic servo system, this paper proposes a motor direct torque control strategy based on sliding-mode variable-structure control optimized by space vector pulse width modulation technology. This paper uses the motor torque mode to control the output pressure of the pump control system. The torque is directly driven to the hydraulic components and internal torque drive unit of the pump control system, the torque is established to directly drive the pump control system framework, and the mathematical model of the hydraulic system is derived and analyzed. The torque control of the servo motor is optimized by the sliding-mode variable-structure control algorithm, which realizes the purpose of improving the dynamic response of the system and the pressure accuracy of the system control.
Several suggestions and comments please find as follows:
(1) There are many inconsistencies in the expression of sliding-mode variable-structure in the paper. It Sometimes is expressed as "sliding-mode variable-structure", sometimes also expressed as "sliding-mode variable structure", especially as the 387th line is misstated as "sliding-file variable-structure". Please express the same professional term uniformly.
(2) "Figure14. Servo motor speed curve" should read "Figure14. Servo motor torque curve"。
(3) The font size of the horizontal and vertical coordinate names of the annotated figures in the paper is inconsistent, as the font size annotated in Figure15 is significantly smaller than that in Figure14, and is more ambiguous.
(4) Whether the description of sliding-mode variable-structure control in lines 146-156 is redundant or unreasonable?
(5) The problem of jitter when designing the sliding-mode variable-structure controller is inevitable, how to solve this problem in this paper?
(6) Figure15 and Figure16 describe the comparison results of the actual pressure curve and the expected pressure curve under the control of sliding-mode variable-structure control and traditional speed change system under step signal, respectively. Why does the traditional control method use a variable-speed system? And does the sliding-mode variable-structure control method also use a variable-speed system? Can the actual pressure value and expected pressure value in Figures15 and Figures16 be described in a single chart to illustrate their control effect?
(7) In the analysis of Figure18, it is mentioned that the traditional variable-speed electro-hydraulic servo system shows obvious overshoot and hysteresis, but there is no overshoot in the curve in the figure?
(8) In view of the comparison of the downforce results based on sliding-mode variable -structure control and traditional variable-speed system described in Figure20-Figure22, the latter has obvious overshoot and hysteresis. It is recommended to add quantitative description.
Comments for author File: 
Comments.docx
Author Response
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Author Response File: Author Response.docx
Reviewer 2 Report
The originality and innovation of the work presented in this paper is good. The paper is written good in English. The contents are presented in a good, structured manner. I suggest accepting the paper. Minor English editing is needed.
Author Response
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Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Review report for
Research on Pressure Control of an Electro-hydraulic Servo System Based on Sliding-Mode Variable-Structure Direct Torque Control
I have carefully checked your modification opinions, which ware in line with the requirements of the revision, and decided to pass!
Good luck to you!
