KONCAR - Machine Condition Monitoring System (MCM)

Its state-of-the-art tools allow monitoring of all key elements and report crucial information to key stakeholders that can react promptly and protect their equipment. Together with our team the customers can define their own scope of monitoring and decide which features to integrate in order to focus on areas that bring the most significant process improvements. 

The system has been successfully installed on more than 2 GVA across the world and is helping customers to make better decisions when operating large energy systems. For more information on installation possibilities visit the solution configurator part or case studies and references to see some of the projects we participated in over the last couple of years.

MCM system measures the values according to the customers’ requirements and with the sampling frequency 10 to 30 kHz. Below is the list of the selected critical values that the system measures.

Vibration monitoring and balancing system unit

The unit measures:

• Relative shaft vibrations (relative to the bearing housing) – relative vibrations measurement is performed by two relative displacement. Sensors are installed in the same plane perpendicularly to each other so it is possible to measure the maximum relative displacement vector and orbit
• Rotating speed measurement – measurement of one pulse per machine revolution

Client software supports the following user screens (HMI):

• Calculation of Smax
• Orbit calculation
• Orbit filtration
• Orbit 3D (orbits on several planes)
• Position of shaft center (on-line)
• Position of shaft center in dependency of rotating speed
• Balancing of a generating unit
• Trends (with restrictive class grouping)
• Alarm/emergency stop

Generator Air Gap Monitoring System
Air gap monitoring is of key importance because the shape and location of the rotor and stator on a large hydro generator are affected by several factors like: centrifugal force, thermal and magnetic forces, mechanical expansion with load due to temperature increase, concrete growth, etc.

Understanding the rotor and stator shapes, positions and minimum air gap dimensions provides the operator with the information needed to remove a machine from service before serious damage from magnetically induced overheating or rotor-to-stator rub occurs.

Client software supports following calculations:

• distribution of air gap for each pole
• rotor and stator roundness
• concentricity
• run out
• deformation of the stator
• magnetic unbalance
• rotor-stator contact

Process values measurement
Process values are imported to monitoring system via standard communication protocols such as MODBUS, IEC104 and others. Most common values to import are active and reactive power, generator currents and voltages, temperatures and others.

Partial Discharge Monitoring System
Partial discharge system consists of 3 couplers per generator installed on generator end winding and processing unit that analyses data collected from couplers installed outside the generator enclosure. Analyzed data is sent to other systems via standard communication protocol as well as through analog outputs (4-20mA).

The system performs standard calculations for signal processing. These calculations are then used as a basis for diagnostic functions that report to users information on machine status. Some of the standard calculations include:

• Mean values calculations (RMS)
• Events calculation
• Alarm calculation (alarm and warning for each measured/processed value)
• Calculation of Smax
• Orbit calculation
• Signal filtering
• Spectral analysis
• Rotating speed calculation

The signal calculations are afterwards presented in the following charts and graphs:

• Bar display (bar)
• Transients display
• Timeline (multi-plot)
• Event (trend) representations (multi-plot)
• Spectral display (2D and 3D)
• Orbit representation (2D and 3D)
• Polar and linear representation for sensors of air gap (minimum, maximum, average, rotor shape)
• Display of the system alarms (active, inactive, confirmed, unconfirmed ...)

To determine machine condition, process data from power plant control (measurement points or calculated values) can be integrated in the system through standard communication.