coal conveying system ಗೆ ಉಪಯೋಗಿಸುವ VCF (Vacuum Contactor-Fuse) ಅನ್ವಯದ ಮಧ್ಯ-ವೋಲ್ಟೇಜ್ ಮೋಟರ್ ನಿಯಂತ್ರಣ ಮತ್ತು ಪ್ರತಿರಕ್ಷಣೆ ಪರಿಹಾರ

1. ಪ್ರಾಜೆಕ್ಟ್ ಪರಿಸರ

ಒಂದು ಕಾಲೀನ ನಿಯೋಜಿತ ವ್ಯವಸ್ಥೆ 15 ಬೆಲ್ಟ್ ನಿಯೋಜಿತಗಳನ್ನು ಹೊಂದಿದ್ದು, ಇವು ಮಧ್ಯ-ವೋಲ್ಟೇಜ್ ಮೋಟಾರ್‌ಗಳಿಂದ ಚಾಲಿತವಾಗಿರುತ್ತದೆ. ಈ ವ್ಯವಸ್ಥೆಯು ಸಂಕೀರ್ಣ ಸಂದರ್ಭಗಳಲ್ಲಿ ಪ್ರಚಲಿತವಾಗಿದೆ, ಮೋಟಾರ್‌ಗಳು ಅನೇಕ ಟನ್ನು ಮತ್ತು ಸಾಮಾನ್ಯ ಆರಂಭಗಳನ್ನು ಗುಂಪು ಮಾಡುತ್ತದೆ. ಈ ಸಮಸ್ಯೆಗಳನ್ನು ದೂರ ಮಾಡಿ ಮೋಟಾರ್ ಆರಂಭದಲ್ಲಿ ಕಾರ್ಯಕಾರಿ ನಿಯಂತ್ರಣ ಮತ್ತು ವಿಶ್ವಸನೀಯ ಸುರಕ್ಷಿತತೆ ನೀಡುವ ಮೂಲಕ, ಪ್ರಾಜೆಕ್ಟ್ ಸಂಪೂರ್ಣವಾಗಿ ವ್ಯಾಕ್ಯುಮ್ ಕಂಟೈಕ್ಟರ್-ಫ್ಯೂಸ್ (VCF) ಸಂಯೋಜನ ಉಪಕರಣಗಳನ್ನು 6kV ಮಧ್ಯ-ವೋಲ್ಟೇಜ್ ಮೋಟಾರ್ ಶಕ್ತಿ ವಿತರಣೆಗೆ ಅನುಸರಿಸುತ್ತದೆ. ಈ ಪರಿಹಾರವು VCF ಯ ತಂತ್ರಜ್ಞಾನ ಲಕ್ಷಣಗಳನ್ನು, ಪ್ರಮುಖ ಸುಧಾರಣೆಗಳನ್ನು ಮತ್ತು ಅನ್ವಯವನ್ನು ವಿವರಿಸುತ್ತದೆ, ಸಮಾನ ಕಾರ್ಯ ಸಂದರ್ಭಗಳಿಗೆ ವಿಶ್ವಸನೀಯ ಸಂ chiếu ನೀಡುತ್ತದೆ.

2. VCF ಯ ಪ್ರಮುಖ ಸುಧಾರಣೆಗಳು ಮತ್ತು ತಂತ್ರಜ್ಞಾನ ಲಕ್ಷಣಗಳು

2.1 ಅಧಿಕ ಉಪಕರಣ ರಚನೆ ಮತ್ತು ಆಳಿತಿ ತಂತ್ರಜ್ಞಾನ

• ​उपकरण प्रकार: यह समाधान आसान इन्स्टॉलेशन, मेंटेनेंस और रिप्लेसमेंट के लिए ड्रॉ-आउट VCF संरचना का उपयोग करता है।
• ​Core Technology: Epoxy resin composite insulation and Automatic Pressure Gelation (APG) technology are utilized, with the vacuum interrupter directly encapsulated in epoxy resin, significantly enhancing insulation performance, mechanical strength, and environmental stability.
• ​Operating Mechanism: The operating mechanism is designed with precision and features low power consumption.

2.2 ಸಂಪೂರ್ಣ ರಚನೆ ಮತ್ತು ವ್ಯಾಪಕ ಅನ್ವಯ

• ​Equipment Composition: The VCF consists of an optimized combination of high-voltage current-limiting fuses (capable of interrupting a wide range of short-circuit currents) and frequently operable VCX vacuum contactors, forming a classic F-C circuit solution.
• ​Core Advantages: It offers long operational life, stable performance, and low noise.
• ​Application Scope: Widely used in high-voltage auxiliary power systems in thermal power plants, as well as in metallurgical, petrochemical, and mining industries. It is suitable for controlling and protecting loads such as high-voltage motors, transformers, and induction furnaces.

2.3 ಉತ್ತಮ ಅನುಕೂಲನ ಮತ್ತು ಸುರಕ್ಷಿತ ಲಕ್ಷಣಗಳು

• ​Cabinet Compatibility: The VCF withdrawable unit matches the dimensions and five-prevention interlocking positions of circuit breaker withdrawable units in 800mm-width middle-mounted switchgear, enabling seamless replacement without any modifications to existing switchgear.
• ​Maintenance Convenience: The withdrawable design allows safe and convenient replacement of high-voltage fuses outside the cabinet.
• ​Holding Method: The vacuum contactor can be configured for electrical or mechanical holding based on customer requirements.
• ​Phase-Loss Protection: Equipped with comprehensive phase-loss protection. In the event of a phase loss, the fuse operates and mechanically interlocks to ensure the VCF disconnects the motor circuit, effectively preventing motor damage due to single-phasing.

3. ಪ್ರಮುಖ ತಂತ್ರಜ್ಞಾನ ಪಾರಾಮೆಟರ್‌ಗಳು (7.2kV ರೇಟಿಂಗ್)

4. ಪ್ರತಿರೋಧ ನಿಯಂತ್ರಣ ಸಿದ್ಧಾಂತ

VCF ಪ್ರತಿರೋಧ ಪ್ರವಾಹದ ಮಾದರಿಯ ಮೇಲೆ ವಿಂಗಡಿಸಲಾಗಿದೆ:

• ​Low Current Range (< 4kA)​: Handled by the vacuum contactor for normal breaking and overload protection.
• ​High Current Range (> 4kA)​: Rapidly interrupted by the high-voltage fuse to address short-circuit faults.
• ​Curve Coordination: The contactor’s protection curve is set below the circuit breaker’s curve to ensure the contactor acts first during overloads. Simultaneously, a properly matched fuse with protection settings lower than the upstream circuit breaker is selected to completely avoid unintended tripping.

5. VCF ವಿರುದ್ಧ ವ್ಯಾಕ್ಯುಮ್ ಸರ್ಕಿಟ್ ಬ್ರೇಕರ್ ಗಳ ಪ್ರಮುಖ ಸುಧಾರಣೆಗಳು

For frequently started and stopped motor loads, VCF offers significant advantages over vacuum circuit breakers:

6. VCF ಆಯ್ಕೆಯ ಮೂಲ: ಫ್ಯೂಸ್ ಆಯ್ಕೆ ಗೈಡ್

The performance of VCF hinges on correct fuse selection, considering the following factors:
Working voltage, working current, motor starting time, starts per hour, motor full-load current, and short-circuit current at the installation point.

6.1 ಆಯ್ಕೆ ನಿಯಮಗಳು ಮತ್ತು ಹಂತಗಳು

1. ​Rated Voltage: The fuse’s rated voltage must not be lower than the system working voltage (7.2kV in this case).
2. ​Rated Current Calculation:
• Use the formula: Iy=N×In×δI_y = N \times I_n \times \deltaIy​=N×In​×δ
• IyI_yIy​: Equivalent current during starting (A)
• NNN: Starting current to full-load current ratio (typically 6)
• InI_nIn​: Motor rated full-load current (A)
• δ\deltaδ: Comprehensive coefficient (based on starts per hour, n, from the table below)

1. ​Curve Matching: Plot the calculated IyI_yIy​ value and the motor’s starting time on the fuse manufacturer’s time-current characteristic curve. Select the fuse rated current corresponding to the curve immediately to the right of this point.
2. ​Additional Check: The selected fuse’s rated current must be ​**> 1.7 times the motor’s full-load current**.

6.2 ಆಯ್ಕೆ ಉದಾಹರಣೆ

For a 7.2kV system with a directly started 250kW high-voltage motor:
In=30AI_n = 30AIn​=30A, 16 starts per hour, starting time of 6s.

• Calculation: Iy=6×30A×2.1=378AI_y = 6 \times 30A \times 2.1 = 378AIy​=6×30A×2.1=378A
• Selection: On the fuse time-current curve, locate the curve to the right of the point (378A, 6s), corresponding to a fuse rated current of 100A.
• Verification: 100A > 1.7 × 30A (51A), meeting the requirement. Thus, a 100A or higher-rated high-voltage motor protection fuse can be selected.

7. ಮುಕ್ತಿ

From a comprehensive cost-performance analysis:

• While vacuum circuit breakers have lower procurement costs, their shorter operational life makes them unsuitable for frequent starts/stops, leading to higher long-term maintenance costs and failure risks.
• The VCF solution combines the advantages of vacuum contactors (long life, low overvoltage, suitability for frequent operation) and fuses (ultra-fast interruption of short-circuit currents), all at an economical overall cost.
• For the coal conveying system and other applications with frequent operation and heavy-load starting characteristics, VCF is an ideal solution offering high performance, reliability, and cost-effectiveness.