Reciprocating Compressor Load Control for Variable Gas Feed

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The variability and intermittency of renewable energy sources pose challenges for stable and efficient operation of industrial gas plants, leading to inefficient operation rates and potential shutdowns due to power shortages, particularly in compressor systems that handle variable gas feed rates and pressures.

Innovation Solution

A method and system for load control of reciprocating compressors that involves controlling a capacity of multiple compressor trains by varying the capacity of each cylinder of some trains and loading or unloading one or more cylinders of each reciprocating compressor stage, using a master/slave control strategy to manage variable incoming gas feed.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If renewable energy sources are used to power industrial gas plants, then environmental sustainability is improved, but power supply stability deteriorates due to natural variability and intermittency

Engineering Contradiction:
Improveenvironmental sustainabilityVSAvoidpower supply stability
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The compressor system implements dynamic capacity adjustment through continuous variation of cylinder capacity in the first subset of compressor trains and stepwise loading/unloading in the second subset, enabling the system to adapt to variable power supply from renewable sources while maintaining stable operation

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The compressor system is divided into two distinct subsets: the first subset handles continuous capacity adjustment for fine-tuned response to power variations, while the second subset provides stepwise capacity changes for coarser adjustments, creating a segmented control architecture that addresses different aspects of variability

Inventive Principle:
Principle #1Segmentation

2Productivity

If compressor capacity is continuously adjusted to match variable gas feed rates, then operational efficiency is improved, but system complexity increases

Engineering Contradiction:
Improveoperational efficiencyVSAvoidcontrol system complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The control system is segmented into two distinct control modes applied to different subsets of compressor trains, with the first subset using continuous capacity adjustment and the second subset using stepwise loading/unloading, allowing complex control functionality to be distributed across simpler, specialized subsystems

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system implements dynamic capacity adjustment through continuous variation of cylinder capacity using suction valve unloaders, enabling real-time matching of compressor output to variable gas feed rates from renewable energy sources while maintaining operational efficiency

Inventive Principle:
Principle #15Dynamics

3Productivity

If compressor trains operate at full capacity to meet peak demand, then productivity is improved, but energy consumption increases during low-demand periods

Engineering Contradiction:
Improvegas production rateVSAvoidenergy consumption
Core Design Contradiction:
ProductivityVSUse of energy by moving object

Solution Approach 1:

The compressor system dynamically adjusts capacity to match actual demand by continuously varying cylinder capacity in the first subset and stepwise loading/unloading in the second subset, ensuring compressors operate at optimal capacity levels rather than running at full capacity during low-demand periods, thereby reducing energy consumption while maintaining productivity when needed

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes operational parameters including cylinder capacity, suction pressure, and discharge pressure to match varying demand conditions, allowing the compressor to operate efficiently across different production levels rather than maintaining fixed parameters that would waste energy during low-demand periods

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP4321754B1A method and system for load control of reciprocating compressors
Publication Date: 2026.03.04 AIR PROD & CHEM INC
  • EP4321754B1 patent drawingFigure 1
  • EP4321754B1 patent drawingFigure 2
  • EP4321754B1 patent drawingFigure 3

AI summary

Controlling a capacity of a compression system in response to the variable incoming gas feed by: i) selectively varying a capacity of a first subset of one or more of compressor trains 202, 204, 206 by continuously varying the capacity of one or more cylinders of the one or more reciprocating compressor stages of the one or more compressor trains of a first subset between a maximum capacity and a minimum capacity; and/or ii) selectively varying a capacity of a second subset of one or more of the compressor trains by fully loading or fully unloading one or more cylinders of the one or more reciprocating compressor stages of the compressor trains of the second subset, wherein the first and second subsets are mutually exclusive.