Welding Power Supply Common Bus Architecture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Welding-type power supplies face challenges in providing consistent output across different input voltages and frequencies, managing dynamic loads, and delivering high-power outputs without incurring switching losses, line losses, heat damage, and electromagnetic interference, while also requiring auxiliary power to mimic utility power without using isolation transformers.
Innovation Solution
A welding-type power supply system with an input circuit providing power to a common bus, a non-isolated auxiliary power circuit, and a controller that manages the power supply to derive welding-type and auxiliary power outputs, utilizing a dual boost preregulator and pulse width modulated half-bridge inverters to maintain power factor correction and avoid isolation transformers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a welding-type power supply uses isolation transformers to provide auxiliary power, then the auxiliary power output is stable and isolated, but the weight and cost of the system increase significantly
Solution Approach 1:
The patent removes the isolation transformer from the auxiliary power circuit while maintaining the essential function of providing stable auxiliary power. The auxiliary power is derived directly from the common bus without transformer isolation, eliminating the weight and cost associated with the transformer while preserving power stability through controlled rectification and filtering.
Solution Approach 2:
The common bus serves multiple functions: it provides power to both the welding-type output circuit and the auxiliary power circuit. This multi-functional approach eliminates the need for separate isolation transformers for auxiliary power, reducing system weight and complexity while maintaining universal input compatibility across single-phase and three-phase configurations.
2Device complexity
If a welding-type power supply is designed for single input voltage, then the power supply is simpler and more cost-effective, but it cannot provide consistent output across different input voltages and frequencies
Solution Approach 1:
The power supply incorporates a universal input circuit designed to accept both single-phase and three-phase inputs at various voltages (115V, 230V, 460V, 575V) and frequencies (50Hz, 60Hz). The circuit architecture uses a common bus that can be charged from different input configurations, allowing the same basic circuit to universally handle multiple input conditions without requiring separate dedicated circuits for each input type.
Solution Approach 2:
The control system dynamically adapts to different input conditions by detecting the input configuration (single-phase or three-phase, voltage level, frequency) and adjusting the operation of the welding-type output circuit and auxiliary power circuit accordingly. This dynamic adaptation allows the power supply to maintain consistent output performance across varying input conditions without requiring complex hard-wired switching between different circuit configurations.
3Use of energy by moving object
If a welding-type power supply uses traditional switching circuits, then the power conversion is efficient, but switching losses, line losses, heat damage, and electromagnetic interference increase
Solution Approach 1:
The power supply employs periodic pulse-width modulated (PWM) switching to control the welding-type output and auxiliary power extraction. By using high-frequency periodic switching with variable duty cycles, the system achieves efficient power conversion while the periodic nature of the switching allows for effective electromagnetic interference filtering and heat dissipation management through synchronized rectification and filtering circuits.
Solution Approach 2:
The patent introduces a common bus as an intermediary energy storage element between the input circuit and the output circuits. This common bus acts as a mediator that smooths out switching transients and electromagnetic disturbances, allowing efficient power conversion while reducing the propagation of electromagnetic interference to the output. The bus capacitance filters high-frequency switching noise while maintaining stable voltage for both welding and auxiliary power loads.
4Device complexity
If auxiliary power is derived from the same power supply as welding power, then the system is more compact and efficient, but the dynamic welding load affects the stability of auxiliary power output
Solution Approach 1:
The power supply is segmented into distinct functional modules: an input circuit that charges the common bus, a welding-type output circuit that draws power from the bus, and an auxiliary power circuit that also draws from the bus but with independent control. This segmentation allows each module to be optimized independently while sharing the common bus, providing both system integration and independent power regulation to maintain auxiliary power stability despite welding load variations.
Solution Approach 2:
The control system implements feedback regulation for both the welding-type output and auxiliary power output. The auxiliary power circuit monitors its own output voltage and current, and the controller adjusts the power extraction from the common bus to maintain stable auxiliary output despite variations in welding load. This feedback mechanism ensures that the auxiliary power remains stable and suitable for powering sensitive equipment even during dynamic welding operations.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system achieves universal input compatibility, efficient power management, and reduced weight and cost by providing stable welding-type and auxiliary power outputs across varying inputs without isolation transformers, effectively addressing the dynamic nature of welding processes and high-power requirements.
Implementation Method 1
dual boost preregulator
Implementation Method 2
pulse width modulated half-bridge inverters
Data Source
AI summary
A method and apparatus for providing welding-type power and auxiliary power includes an input circuit, a welding-type output power circuit, an auxiliary power circuit, and a controller. The input circuit receives input power and provides power to a common bus. The welding-type output power circuit receives power from the common bus and provides welding-type output power. The auxiliary power circuit receives power from the common bus and provides non-isolated auxiliary output power. The controller controls the auxiliary power circuit and the welding-type output power circuit.