Closed-Loop Hydraulic Pump Control for Flow and Pressure Setpoints
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional fluid pumping systems in industrial applications face inefficiencies due to the inability to precisely control flow and pressure, leading to increased energy consumption and complexity, along with a higher risk of pump cavitation and contamination in open-loop systems.
Innovation Solution
A fluid pumping system incorporating a variable-speed and/or variable-torque pump, proportional control valve assemblies, and a controller that synchronizes the operation of the pump and valve to precisely control flow and pressure, forming a closed-loop system for improved efficiency and reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If a conventional hydraulic pump is run at full speed or constant speed to ensure adequate pressure, then the system maintains sufficient pressure for flow control devices, but energy consumption increases and the pump operates inefficiently when system load is low
Solution Approach 1:
The patent applies variable speed control to the hydraulic pump, allowing it to dynamically adjust its operating speed based on actual system demand. The controller modulates the pump speed to match the flow requirements of hydraulic actuators, enabling the pump to operate efficiently across varying load conditions rather than running at constant full speed.
Solution Approach 2:
The system implements a closed-loop control architecture where sensors monitor actual flow and pressure conditions, and the controller uses this feedback to continuously adjust pump speed. This feedback mechanism ensures the pump maintains adequate pressure while consuming only the necessary energy to meet actual system demands.
2Measurement precision
If flow control devices are added to precisely control flow in the system, then flow control precision improves, but system complexity increases and additional hydraulic fluid is required for hydraulic controls
Solution Approach 1:
The patent replaces traditional hydraulic flow control devices with an electrically controlled pump system. The variable speed pump, controlled by an electronic controller receiving signals from the operator, directly regulates flow to hydraulic actuators without requiring separate hydraulic flow control valves or additional hydraulic control circuits.
Solution Approach 2:
The variable speed pump serves multiple functions: it provides both pressure generation and flow control in a single component. The pump's variable displacement mechanism and electronic control system integrate functions that would traditionally require separate pressure relief valves and flow control valves, simplifying the overall system architecture.
3Reliability
If an open-loop system with a large fluid reservoir is used to maintain fluid temperature and prevent cavitation, then cavitation risk is reduced, but system complexity increases and the system becomes susceptible to contamination and damage in harsh environments
Solution Approach 1:
The patent extracts and eliminates the large external fluid reservoir from the hydraulic system. The closed-loop system recycles hydraulic fluid directly between the pump and actuators without requiring a separate reservoir, removing the complexity associated with reservoir maintenance, contamination filtration, and fluid level monitoring.
Solution Approach 2:
The closed-loop system maintains continuous circulation of hydraulic fluid through the pump and actuators, ensuring constant fluid movement that prevents cavitation without requiring a large reservoir. The fluid continuously returns to the pump inlet after performing work, maintaining adequate supply and preventing air ingestion.
Data Source
AI summary
A fluid-driven actuator system includes a fluid-driven actuator and at least one proportional control valve and at least one pump connected to the fluid-driven actuator to provide fluid to operate the fluid-driven actuator. The at least one pump includes at least one fluid driver having a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from the pump inlet to the pump outlet. The fluid-driven actuator system also includes a controller that establishes at least one of a speed and a torque of the at least one prime mover to adjust at least one of a flow in the fluid-driven system to a flow set point and a pressure in the fluid-driven actuator system to a pressure set point and concurrently establishes an opening of the at least one proportional control valve to adjust at least one of the flow to the flow set point and the pressure to the pressure set point.