In thermal power plant desulfurization systems, conventional blowers inherently present challenges such as high energy consumption and risk of lubricant contamination. The Greatall High-Voltage Magnetic Levitation Blower utilizes an Active Magnetic Bearing (AMB) system to achieve oil-free, non-contact, and frictionless rotor operation. Consequently, the operation and maintenance (O&M) paradigm shifts fundamentally from traditional schedule-based mechanical overhauls to digital condition monitoring and predictive maintenance.
1. Restructuring of O&M Logic
| O&M Dimension | Conventional Blower | Greatall High-Voltage Magnetic Levitation Blower |
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Maintenance Strategy | Periodic mechanical maintenance (scheduled oil/bearing replacement) | Condition monitoring and precise, demand-driven maintenance |
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Vibration Characteristics | Severe mechanical vibration | AMB-supported rotor with zero rigid mechanical contact, effectively suppressing operational vibration |
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Fault Manifestation | Abnormal noise, lubricant leakage, abrupt bearing temperature spikes | Rotor displacement peak-to-peak values exceeding protection thresholds |
2. Key Elements of Daily Inspection
To ensure long-term unit operation within the high-efficiency zone, field inspections must focus on the following core physical variables and control parameters:
● Filter Differential Pressure Control: The differential pressure across the primary and precision filters must be monitored closely. Filters must be replaced immediately upon exceeding the configured thresholds to prevent increased airflow resistance, which may induce blower surge.
● Interlocking Process Parameter Analysis: Real-time interlocking analysis covering outlet flow, discharge pressure, and desulfurization slurry pH must be conducted to strictly ensure the operational duty point does not deviate from the high-efficiency zone.
● Verification of Bearing Levitation Status: Rotor displacement offset, unbalance, magnetic bearing coil currents, and loads must be monitored in real time via the Human-Machine Interface (HMI). Abnormal fluctuations in magnetic bearing loads typically serve as early warning signs of unstable operating conditions or initial entry into the surge zone.
● Aerodynamic Piping Tightness: Blower outlet piping, blow-off valves, and flange connections must be inspected regularly to eliminate active power losses resulting from gas leakage.
3. Standardized Maintenance Schedule
In accordance with the stringent conditions of power plants characterized by high dust concentration and continuous operation, Greatall recommends compliance with the following maintenance schedule:
● Monthly (Primary Filter): Inspect the dust accumulation on the primary filter cotton and compare the differential pressure data. Under standard operating conditions, the replacement interval is once per month ; this frequency must be increased if ambient dust concentration is high.
● Semi-Annually (Precision Filters & Electrical Systems): Replace precision filters (once every 6 months) ; verify the sealing integrity of blow-off valves and check valves ; perform tightening torque verifications on main circuit and power electrical bolts inside the control cabinet ; clean the cooling fins of the variable frequency drive (VFD) and control systems.
● Annually (Comprehensive Overhaul): Inspect the VFD excitation modules and cooling fans thoroughly ; measure the motor insulation impedance of the stator windings using a megohmmeter ; calibrate displacement and pressure sensors ; inspect power and control cable entry interfaces to confirm dustproof sealing ; execute Uninterruptible Power Supply (UPS) energy storage system charging and discharging tests to guarantee sufficient autonomy for safe rotor levitation landing in the event of a plant power interruption.
4. Common Fault Diagnosis and Emergency Response
The Greatall magnetic levitation blower integrates a comprehensive self-diagnostic system. When a protective lockout is triggered, rapid troubleshooting can be performed by referencing the following table:
| Fault Description | Root Cause Assessment | Recommended Response Strategy |
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Not Floated | Displacement offset exceeded limits or the levitation command was not activated | Verify that no critical faults exist, then press the "FLOAT" button on the MBC controller, or hold the hardware reset button for over 5 seconds to activate the levitation command. |
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Abnormal Inlet Differential Pressure | Severe clogging of the inlet filter or drift of the differential pressure transmitter | Evaluate the actual contamination level of the filter; if the differential pressure is normal, calibrate or replace the inlet differential pressure sensor. |
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Abnormal Discharge Pressure | Flow restriction in the downstream process piping network or incomplete opening of the outlet valve | Check the opening status of the outlet isolation valve and confirm that no abnormal backpressure exists in the discharge piping. |
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Abnormal Discharge Temperature | Prolonged operation outside the high-efficiency zone, system surge, or severe filter clogging | Inspect flow passage tightness, clean primary and precision filters, and adjust the process load matching. |
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Maintenance Interval Alarm | Cumulative running time has reached the preconfigured maintenance threshold | Schedule the corresponding level of physical maintenance according to the "Standardized Maintenance Schedule" and reset the operational timer in the control system. |
5. O&M Red Lines
● ⚠️ Red Line 1: Opening cabinet doors to clean filter cotton during operation is strictly prohibited.
○ Potential Risk: Opening doors during operation causes unfiltered, high-concentration external dust to be directly drawn into the high-speed rotor flow passages by negative pressure, compromising blade dynamic balance ; concurrently, high-voltage hazards exist inside the control cabinet.
● ⚠️ Red Line 2: Unauthorized modification of MBC (Magnetic Bearing Controller) parameters is strictly prohibited.
○ Potential Risk: The stiffness and damping coefficients of the active magnetic bearings are based on precise dynamic calculations. Unauthorized modifications can easily induce rotor dynamic instability, leading to catastrophic mechanical collisions between the rotor and backup bearings. Such operations must be authorized exclusively by Greatall OEM engineers.
● ⚠️ Red Line 3: Forcible startup of the drive motor while the rotor is not fully levitated is strictly prohibited.
○ Potential Risk: If the rotor is not securely positioned within the electromagnetic levitation centerline, forcing the startup of the high-frequency permanent magnet synchronous motor will cause abnormal engagement of the backup bearings, leading to a sharp decline in lifespan or severe damage to the backup bearings.
Conclusion
The core philosophy governing the O&M of Greatall high-voltage magnetic levitation blowers can be defined as "minimal manual intervention, profound data insight". Power plant O&M teams can achieve highly efficient, low-consumption equipment operation across the entire lifecycle by strictly adhering to standardized filter maintenance and closely monitoring key electromagnetic and aerodynamic indicators.
