Hydraulic Pump Torque Control via Dynamic Map Updates

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing hydraulic pump control systems in construction machines fail to smoothly adjust output torque when the dynamic characteristic of the engine changes, leading to decreased workability and performance due to unintentional decreases in engine speed and increased operation time.

Innovation Solution

A method and device that monitor engine dynamic characteristics, generate a new torque change rate map for each load range, and update the existing torque change rate map to reflect changes in engine performance, ensuring the hydraulic pumps are controlled effectively even when engine dynamics deviate from the normal range.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a torque change rate map is loaded for each load range to control hydraulic pump output torque, then the dynamic characteristic of the engine is reflected in the control, but when the dynamic characteristic of the engine changes, the already loaded torque change rate map cannot smoothly control the hydraulic pump

Engineering Contradiction:
Improveadaptability to engine dynamic characteristicVSAvoidcontrol reliability when engine characteristic changes
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent implements dynamic updating of the torque change rate map based on real-time detection of engine dynamic characteristics. When the engine's dynamic characteristic changes (detected through engine speed response to torque changes), the control system automatically updates the torque change rate map to match the new engine characteristics, transforming a static control parameter into a dynamic one that adapts to engine condition changes.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system employs feedback mechanisms by continuously monitoring engine speed and detecting actual engine dynamic characteristics during operation. The detected characteristics are used to determine whether updating the torque change rate map is necessary, creating a closed-loop control system that ensures the control parameters remain aligned with the actual engine state.

Inventive Principle:
Principle #23Feedback

2Productivity

If the pump is controlled by loading a torque change rate map for each load, then output torque control reflects engine dynamic characteristic, but when engine dynamic characteristic changes, the control system cannot smoothly control the hydraulic pump

Engineering Contradiction:
ImproveworkabilityVSAvoidadaptability to changed engine characteristic
Core Design Contradiction:
ProductivityVSAdaptability or versatility

Solution Approach 1:

The control system transitions from using fixed, pre-loaded torque change rate maps to dynamically updating these maps based on real-time engine performance detection. This allows the system to maintain high productivity by adapting to engine characteristic changes that occur during operation, such as those caused by performance degradation over time or environmental variations.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the parameters of the torque change rate map based on detected engine dynamic characteristics. When the engine's response to torque changes deviates from the original map assumptions, the system updates the map parameters to reflect the new engine state, ensuring continued optimal control performance and productivity.

Inventive Principle:
Principle #35Parameter changes

3Device complexity

If a fixed torque change rate map is used for hydraulic pump control, then the control system is simple, but it cannot adapt when engine performance degrades over time

Engineering Contradiction:
Improvecontrol system complexityVSAvoidadaptability to engine performance degradation
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The control system performs self-updating by automatically detecting engine dynamic characteristic changes and updating its own torque change rate map without requiring external intervention or complex manual reconfiguration. This self-service capability allows the system to maintain adaptability while keeping the overall control architecture relatively simple.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system introduces dynamic updating capability into an otherwise simple control architecture. By implementing conditional updates based on detected engine characteristic changes, the system maintains simplicity during normal operation while gaining adaptability when engine performance degrades, achieving a balance between complexity and versatility.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP2980326B1Device and method for controlling hydraulic pump in construction machine
Publication Date: 2020.02.05 DOOSAN INFRACORE CO LTD
  • EP2980326B1 patent drawingFigure 1
  • EP2980326B1 patent drawingFigure 2
  • EP2980326B1 patent drawingFigure 3

AI summary

Disclosed are a device and a method for controlling a hydraulic pump in a construction machine, the method including: an engine dynamic characteristic change checking step S20 of checking whether a dynamic characteristic of an engine deviates from a predetermined permissible range when a load is applied to the hydraulic pump and a pump load reaches pump torque required by the hydraulic pump; a pump load applying step S40 of when the dynamic characteristic of the engine deviates from the predetermined permissible range in the engine dynamic characteristic change checking step S20, applying a pump load to the hydraulic pump so as to increase the pump torque to predetermined torque with a predetermined change rate; an information collecting step S50 of collecting information including engine speed information, swash plate angle information of the pump, and pressure information of discharged working oil, which is generated when the pump load is applied in the pump load applying step S40; a map data generating step S60 of generating a new torque change rate map 220a by generating a torque change rate for each load section based on the information collected in the information collecting step S50; and an updating step S80 for updating an existing torque change rate map 220 to the new torque change rate map 220a generated in the map data generating step S60, in which the hydraulic pump is controlled by the new torque change rate map 220a updated in the updating step S80.