Implementation of Single Feedback Control Loop for Constant Power Regulated Swash Plate Axial Piston Pumps
Bibliographic record
Abstract
Variable displacement pumps are often used in both industrial applications and mobile hydraulic machinery. In such pumps, flow rate is dictated by the system requirements. Mathematical model has been previously developed to simulate the dynamic performance of the electrically controlled constant power regulated swash plate axial piston pump with conical cylinder blocks. The pump is currently equipped with a double negative feedback control loop with an inner control loop to control the position of proportional valve using PID controller. Consequently, the proportional valve distributes the control pressure across the two sides of a control piston that is mechanically attached to the pump swash plate in order to change the pump flow rate. The outer control loop is used to control the pump flow rate in accordance with the system pressure change in order to keep the constant power operation using PD controller. For the convenience of pump constant power operation, PD controller is tuned to keep limited power shocks on the pump drive motor during the transient periods. The selected PD parameters result in relatively reduced settling time. Consequently swash plate steady state vibration appears.Purpose of this paper is to investigate features of the pump performance in view of an alternative control scheme. Counting on the relatively good open loop static characteristics of the proportional valve, a control scheme with a single control feedback loop is proposed to simplify the currently used control scheme. Using such single feedback control loop reduces the pump production cost and leads to have less responsive system that suppresses the steady state vibration of the swash plate. Simulation results are verified experimentally and qualitatively compared with the results when the original control scheme is used. Results are presented and discussed.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".