Submerged Arc Furnace Electrode Length Measurement
Solution Overview
Problem
Existing methods for determining the length of electrodes in submerged arc furnaces do not account for the variability of arc burning parameters in reductive atmospheres and other electrode performance parameters, leading to unsatisfactory solutions.
Innovation Solution
A method that measures the voltage between the furnace hearth and the electrode casings, along with derivatives of current measured on the secondary side of the transformer, to determine the electrical parameters of the areas surrounding the electrodes, allowing for the calculation of electrode lengths.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If existing methods are used to determine electrode length, then the measurement can be performed, but the measurement precision is insufficient due to not accounting for arc burning parameter variability and electrode performance parameters
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting the measurement model to account for variability in arc burning parameters and electrode performance parameters. The system continuously monitors and adapts to changes in electrical characteristics, ensuring accurate electrode length measurement despite varying operating conditions such as temperature, current, and arc stability.
Solution Approach 2:
The patent implements feedback mechanisms by continuously monitoring electrical parameters (current, voltage, power factor) and using this information to update the electrode length calculation. The system compares measured values with expected values and adjusts the measurement model accordingly, providing real-time correction for measurement drift and improving overall precision.
2Measurement precision
If electrode length is determined by interrupting furnace operation for manual measurement, then measurement precision can be improved, but loss of time increases significantly
Solution Approach 1:
The patent enables continuous electrode length measurement during furnace operation by using electrical parameter monitoring that does not require interrupting the melting process. The system continuously captures electrical characteristics (current, voltage, power factor) and processes them to determine electrode length in real-time, eliminating downtime while maintaining measurement accuracy.
Solution Approach 2:
The patent replaces manual mechanical measurement methods with electrical parameter-based measurement. Instead of physically measuring electrodes during downtime, the system uses electrical characteristics (current, voltage, power factor) captured during normal operation to calculate electrode length, substituting mechanical measurement with electrical sensing and computation.
3Measurement precision
If complex measurement systems are implemented to account for all electrode parameters, then measurement precision improves, but device complexity increases
Solution Approach 1:
The patent achieves multi-functionality by using a unified measurement system that monitors multiple electrical parameters (current, voltage, power factor) simultaneously to determine electrode length. The same measurement infrastructure serves multiple purposes: tracking electrode position, monitoring arc stability, and detecting process anomalies, thereby reducing overall system complexity despite the comprehensive nature of the measurements.
Solution Approach 2:
The patent uses electrical parameter measurements as a copy or proxy for direct physical measurement of electrode length. Instead of directly measuring the electrode physically, the system measures electrical characteristics that correlate with electrode position and length, creating an indirect but accurate representation that simplifies the measurement approach while maintaining precision.
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
This method enables accurate determination of electrode lengths and their position relative to the furnace hearth without interrupting furnace operation, improving process control and reducing the need for downtime.
Implementation Method 1
determining the electrical parameters of the areas immediately surrounding the electrodes
Implementation Method 2
derivatives of the current measured on the secondary side of the transformer
Implementation Method 3
generate an arc in the working area
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A method for determining the length of the electrodes of a submerged arc furnace and the position of those electrodes relative to the furnace hearth, characterised in that the voltage of the electrodes is measured between the bottom of the furnace hearth and the moving terminals on the electrode casings in their upper position and the current derivatives measured on the secondary side of the transformer to determine the electrical parameters of the area immediately surrounding the electrodes, following which the length of the electrodes is calculated, with measurements being taken at the time iek(tk) at which both the electrode current iek(tk) and the desired voltage waveform on the equivalent resistance of the peri-electrode area uek(tk) take the value of zero. The invention also comprises a measuring system for determining the resistance of the electrodes (1, 2, 3) of a submerged arc furnace (4) supplied from a furnace transformer (5), characterised in that it comprises a Rogowski coil system (RC1, RC2, RC3) for measuring the current derivatives in the high-current line supplying the electrode array (1, 2, 3) and an array of voltmeters (7, 8, 9) for measuring the voltage between the counter-electrode and the predetermined moving terminal of the a given electrode (1, 2, 3) on the electrode casing the upper position of the electrodes.