Choosing variable-frequency drive systems for the mining process units
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2021-01-01 |
| Journal | E3S Web of Conferences |
| Authors | Наталья Николаевна Кугушева, А С Семенов, Ilya Yakushev, Svetlana Pavlova, Ayaal Egorov |
| Institutions | Nizhny Novgorod State Pedagogical University, Nizhny Novgorod State Technical University |
| Citations | 9 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Variable-Frequency Drives in Diamond Mining
Section titled “Technical Documentation & Analysis: Variable-Frequency Drives in Diamond Mining”Executive Summary
Section titled “Executive Summary”This analysis bridges the findings of the research on Variable-Frequency Drive (VFD) optimization in diamond mining with 6CCVD’s core expertise in advanced diamond materials for high-power electronics. The reliability and efficiency gains sought by the mining industry are fundamentally dependent on the thermal management of modern Frequency Converters (FCs).
- Application Focus: Optimization of VFD systems for energy-intensive diamond mining units (up to 5 MW capacity), targeting improved energy efficiency and reduced maintenance costs.
- Performance Requirement: Critical mechanisms (e.g., dredge hoists) require high-accuracy torque control (± 2% to ± 5%), necessitating advanced vector control FCs.
- Economic Finding: Low-Voltage FCs (LVFC) demonstrated a faster payback period (5 years) compared to High-Voltage FCs (HVFC) (6 years) for a 315 kW pumping unit, driven primarily by lower annual operating costs.
- Reliability Mandate: The paper stresses the need to select FCs based on failure criticality and reliability, justifying the use of high-cost, high-performance converters where necessary.
- 6CCVD Value Proposition: Modern FCs rely on high-power semiconductor devices (IGBTs, SiC, GaN). The reliability and power density required for these systems are directly enabled by CVD diamond heat spreaders, which offer the highest thermal conductivity available.
- Strategic Insight: As mining enterprises shift toward high-reliability, high-power density multilevel converters, 6CCVD provides the essential thermal management substrates (SCD and PCD) required to meet stringent operational demands.
Technical Specifications
Section titled “Technical Specifications”The following hard data points were extracted from the comparison of low-voltage frequency converters and the economic analysis of VFD implementation options.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Typical Unit Capacity | Up to 5 | MW | Single technological units in mining |
| Compared FC Power (LV) | 200 - 220 | kW | Low-voltage frequency converters (380 V) |
| Compared FC Voltage (LV) | 380 | V | Standard low-voltage system |
| Voltage Tolerance | + 10, -15 | % | Acceptable input voltage variation |
| Speed Maintaining Accuracy (Vector Control) | ± 0.1 - ± 0.2 | % | Required for high-precision control |
| Torque Maintaining Accuracy (Vector Control) | ± 2 - ± 5 | % | Critical for mechanisms like dredge hoists |
| 1 min Overload Margin | 120 - 160 | % | Rated output current |
| High-Voltage VFD Capacity (Example) | 315 | kW | Pumping unit modernization case study |
| LVFC Capital Investment (315 kW) | 6,247.5 | KRUB | Total capital cost (including installation) |
| HVFC Capital Investment (315 kW) | 5,705.5 | KRUB | Total capital cost (including installation) |
| LVFC Payback Period | 5 | Years | Based on Net Present Value (NPV) calculation |
| HVFC Payback Period | 6 | Years | Based on Net Present Value (NPV) calculation |
Key Methodologies
Section titled “Key Methodologies”The research focused on a structured technical and economic comparison of VFD systems for diamond mining applications.
- Operational Practice Analysis: Study of existing VFD implementation and operation practices across various diamond mining process units (e.g., main fans, slurry pumps, dredge hoists) to identify common problems and inefficiencies.
- Control Mode Evaluation: Technical comparison of low-voltage frequency converters (FCs) of similar power (200-220 kW) but utilizing different control methods (Scalar vs. Vector control) to determine suitability for high-torque, low-speed applications.
- Economic Indicator Calculation: Detailed calculation of Capital Investment (CI) and Operating Costs (OC) for two VFD implementation options (High-Voltage vs. Low-Voltage) for a 315 kW pumping unit.
- Financial Modeling (NPV): Application of the Net Present Value (NPV) technique over a 7-year planning horizon, considering a discount factor of 0.15 and an annual electricity cost increase of 10% max, to determine the projected profitability and payback period.
- Reliability Classification: Formulation of guidelines requiring the classification of diamond mining equipment based on process requirements and the criticality of equipment failures to justify the selection of reliable, high-cost converters.
6CCVD Solutions & Capabilities
Section titled “6CCVD Solutions & Capabilities”The paper highlights that modern FCs rely on advanced power circuitry (IGBTs, multilevel converters) to achieve high efficiency and precise control (vector control). The reliability and power density of these systems are critically limited by thermal dissipation. 6CCVD specializes in providing the MPCVD diamond materials necessary to manage the extreme heat loads generated by these high-performance semiconductors.
| Application Requirement | 6CCVD Material Solution | Customization & Capability |
|---|---|---|
| High Thermal Dissipation (For IGBTs/SiC modules in MW-class FCs) | Thermal Grade Single Crystal Diamond (SCD) | SCD plates up to 500µm thick, offering thermal conductivity >2000 W/mK, ensuring maximum heat extraction and extending semiconductor life. |
| Large Area Substrates (For high-power multilevel converters) | Polycrystalline Diamond (PCD) Wafers | Custom dimensions up to 125mm diameter (inch-size), providing robust, cost-effective thermal substrates for large-format power modules. |
| Interface Optimization (Minimizing thermal resistance) | Precision Polishing & Metalization | SCD polished to Ra < 1nm; PCD polished to Ra < 5nm. Internal metalization capabilities (Au, Pt, Ti, W, Cu) for direct bonding and integration into power electronic packaging. |
| High-Accuracy Control Systems (Vector Control) | Custom Diamond Heat Spreaders | We supply custom-cut and laser-machined diamond components tailored to the specific geometry of high-density power stacks, crucial for maintaining the precise operating temperatures required for accurate vector control. |
Engineering Support
Section titled “Engineering Support”The research emphasizes that the selection of FCs must be based on a detailed survey of the facility and process requirements. 6CCVD’s in-house PhD team provides expert consultation on thermal management design, assisting engineers in selecting the optimal diamond material (SCD vs. PCD) and configuration (thickness, metalization scheme) for similar high-power Variable-Frequency Drive (VFD) projects. We ensure that the thermal solution matches the reliability and performance demands of critical mining equipment.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
Mining enterprises are energy intensive facilities. The capacity of single technological units can reach 5 MW. Variable-frequency drive systems are often used to set them in motion. The paper analyzes the features of choosing and using variable-frequency drives under diamond mining conditions. The study objective is to formulate and formalize the problems of introducing and operating variable-frequency drives at diamond-mining enterprises to further develop and implement guidelines for improving the performance of this drive type. To achieve this objective, the use of variable frequency drives in various process units of diamond mining should be studied and analyzed. The units are considered, for which in recent years, electric drive systems have been groundlessly (according to the authors) chosen by the engineering staff of enterprises. A technical and economic comparison of low-voltage frequency converters with the same power but different control modes is performed. The economic indicators of introducing high-voltage and low-voltage frequency converters into an existing electric drive system are calculated and represented as a comparative table. Conclusions are made on the need to proceed with the research and develop guidelines for implementing frequency converters at diamond-mining enterprises.