Welding Power Supply Dynamic Current Control for Stick Arc Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electronic controlled inverter/high frequency switching welding power sources fail to replicate the desirable welding characteristics of DC generators, particularly in stick welding applications, lacking the flexibility and control necessary for high-quality pipe welding.
Innovation Solution
A welding power supply system with dynamic current responses, incorporating power conversion circuitry, voltage sense circuit, and control circuitry to mimic DC generator behavior, allowing adjustable current ramping rates and exponential control of current based on output voltage, enabling positive and negative droop control and improved arc management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If conventional electronic controlled inverter/high frequency switching welding power sources are used, then the device complexity is reduced compared to DC generators, but the welding characteristics and arc control quality deteriorate
Solution Approach 1:
The patent copies the desirable welding characteristics of DC generators by implementing a control system that replicates their dynamic current response behavior. The inverter power source mimics the DC generator's arc voltage-current relationship and transient response through software control algorithms, achieving similar welding performance without the mechanical complexity of a DC generator.
Solution Approach 2:
The patent changes the control parameters dynamically during welding operations. The control system adjusts current ramping rates, arc voltage thresholds, and response characteristics in real-time based on welding conditions, enabling the electronic power source to replicate the adaptive behavior of DC generators across different welding scenarios.
2Manufacturing precision
If DC generator welding machines are used, then the arc control and welding characteristics are improved, but the device complexity increases
Solution Approach 1:
The patent replaces the mechanical system of a DC generator with an electronic inverter-based system. The mechanical field-controlled generator is substituted with solid-state power electronics and digital control circuitry that replicates the desired welding characteristics through software algorithms, eliminating mechanical complexity while maintaining performance.
Solution Approach 2:
The patent introduces a control system as an intermediary between the power source and the welding arc. This control layer processes sensor data, implements control algorithms, and adjusts power delivery to replicate DC generator behavior, serving as a mediator that translates electronic power into arc-friendly output characteristics.
3Device complexity
If conventional inverter power sources with fixed current limiting are used, then the device simplicity is maintained, but the adaptability to different welding conditions deteriorates
Solution Approach 1:
The patent implements dynamic control where the current ramping rate and response characteristics change continuously based on real-time welding conditions. The system transitions between different control modes (constant current, constant voltage, and intermediate regions) and adjusts parameters like dig limit, arc control, and slope dynamically, enabling adaptation to various welding scenarios while maintaining a single device design.
Data Source
AI summary
An example welding power supply includes: power conversion circuitry configured to convert supply power to welding current and to output the welding current to at least one of a shielded metal arc welding (SMAW) electrode or a gouging torch; a voltage sense circuit configured to measure an output voltage of the power conversion circuitry; and control circuitry configured to: control the power conversion circuitry using a current-controlled control loop based on a target current; while the output voltage is above a lower voltage limit, control the target current based on a difference between a reference voltage and the output voltage; and in response to detecting that the output voltage has decreased below the lower voltage limit, control a welding current output by the power conversion circuitry based on a first exponential relationship.