Acoustic Monitoring Firmware

The acoustic monitoring firmware supports 18 input channels. The main features are:

• RMS Broadband Calculation - Calculates the broadband root-mean-square (RMS) energy of the time-domain sampled data in the frequency range of 0 to 5000 Hz. The output is the input of the RMS Scan Average.


• RMS Scan Average - Average multiple scans of broadband RMS values. A scan is defined by the amount of time-domain sampled combustion data to calculate a windowed FFT of some defined length. The output is the system input, SIGx (where x is the channel number), passed to the controller.


• Windowed FFT - Calculates the frequency domain peak-to-peak magnitude and bin frequency, based on time-domain sampled combustion input data. The configuration defines the type of FFT window function used, the FFT length (amount of input data collected for the calculation), and the sample frequency. The output feeds the Peak-to-Peak Scan Average.


• Peak-to-Peak Scan Average - Provides a frequency domain peak-to-peak magnitude average per frequency bin, over multiple scans. The configuration defines the number of scans used in the rolling average calculation. The output is the input for the Six-Band Sort function.


• Six-Band Sort - Average frequency domain peak-to-peak data is sorted into six separate frequency bands, as displayed in the following table.

The maximum of the average peak-to-peak magnitudes from each frequency band and its corresponding frequency bin are selected and output as system inputs for the controller.

• Band n Average - Calculates the average peak-to-peak magnitude over all enabled healthy input channels, based on the output of the Six-Band Sort.


• Band n Maximum - Calculates the maximum peak-to-peak magnitude over all input channels enabled, based on the Six-Band Sort data. The six frequency band maximums are output for use by the controller.


• Band n Limit Check- A frequency band limit check based on the Band n Maximum output data.


•  

A/D Compensation

The A/D compensation function eliminates any gain or offset error due to initial component inconsistency. An auto-calibration function runs each time the module is reset. The auto-calibration function compares each of the 18 analog channels against a standard A/D channel. This A/D channel is calibrated using a standard high-precision voltage reference and the A/D common.

Input Units to Engineering Value Conversion

The Acoustic Monitoring System converts the hardware input units to the engineering units (EU) needed for the system calculation. For the conversion of mV to psi, the range is 20 to 600 mV per psi. Four configuration parameters are provided per channel to define the equation for the transfer function.

Value (EU in counts) = GUnitConversion * Input (millivolts in counts) + Offset where

GUnitConversion = (High_Value - Low_Value) / (High_Input - Low_Input)

Offset = High_Value - GUnitConversion * High_Input

where

High_Value, Low_Value, High_Input + Low Input are the configuration parameters.

RMS Broadband Calc

RMS Scan Avg

where ch x = 1 – 18

where band n = 1 – 6 & ch x = 1 – 18

where band n = 1 – 6

Ch –

where x = 1 - 18

Pk-Pk Scan Avg

6-Band Sort

Select a maximum pk-pk amplitude for each of the 6 configurable frequency bands

Band n Avg.

Average channels 1 thru x in Freq. Band n

Band n Max

Sel max. Mag. From the x ch(s) for Freq. Band n

Band n Limit Check

Check Band n Max. out against Limit

SIGNAL SPACE INPUTS

Windowed FFT

Acoustic Monitoring Block Diagram

A/D Gain Adjust

The configuration parameter, Gain, controls the channel gain in the hardware. This parameter is defined for each channel. This allows low-level signals to be amplified to provide better resolution in the A/D conversion hardware. The gain options are 1x, 2x, 4x, and 8x. The channel control writes the gain setup to the FPGA input amplifier 4x and 2x gain control registers. The signal level calculated by PAMB firmware will not change with the Gain parameter because the signal is divided by the gain factor in the firmware, resulting in a net gain of 1 for the signal regardless of the gain factor used. The maximum expected signal level should not exceed 10 V (saturation) after the gain is applied as indicated in the following table.

RMS Calculation and Rolling Average

The RMS calculation function performs an RMS calculation on the ac acoustic information sampled for a given scan. The RMS is defined as follows:

rms_Chx = SQRT ( (AC_Input(0)**2 + AC_Input(1)**2 + ... + AC_Input(Buffer_Length)**2) / Buffer_Length)

Where x is the channel number.

The rolling average function provides a smoothing function to reduce the vibration in the signal.

Capture Lists

Two capture lists are available, as follows:

•      Trip Capture Lists - This function provides circular buffers that input internally calculated data, which is selected based on a configuration parameter. The circular buffers can capture up to 32 scans of information for each of 18 channels. The following internal data can be captured:

-         Time-domain sampled input data (in volts)

-         Frequency-domain FFT peak-to-peak magnitude (in volts)

-         FFT output data with transducer compensation (in volts)

-         FFT output data with transducer compensation (in EU)

-         Scan-averaged FFT output data with transducer compensation (in EU)

Trip Capture Lists are pre-triggered, meaning for a 32 scan FFT average, data is scanned 32 times before the triggered event and none after the event. The triggered event is activated by the signal space input, TripCapReq. Running on the HMI or OSM computer, AM Gateway software uploads the captured lists and transfers the data to the Atlanta Remote DLN Tuning Center for analysis.

•      User Capture Lists - This function provides circular buffers that are only one scan in length (compared to the Trip Capture, with 32 scan buffers). The User Capture buffers can input the same internal data as the Trip Capture buffers. The AM Gateway software can upload these lists. User capture lists are activated through the AM Gateway or other compatible applications.

PAMB Acoustic Monitoring Diagnostic Support

Ch x AC sampled Data (volts)

Ch x Windowed FFT data (volts)

Ch x FFT w Transducer Compensation (volts)

Ch x FFT w Transducer Compensation (EU)

Ch x FFT w Trans Comp & Scan Avged (EU)

Select

Capture selected data for each channel. Numbers of data samples determined by the FFT length and number of Scans averaged

Start Capturing data

Ch – Capture List

Trip Capture Lists

A User Capture List is also Provided but is only 1 Scan deep

Channel Health Status

Specifications

Diagnostics

The I/O module performs the following self-diagnostic tests:

• A power-up self test that includes checks of RAM, flash memory, Ethernet ports, and most of the processor board hardware


• Continuous monitoring of the internal power supplies for correct operation
  
  
  
  • A check of the electronic ID information from the terminal board, acquisition board, and processor board ID to confirm that the hardware set matches, followed by a check that the application code loaded from flash memory is correct for the hardware set.
  
  
  • Each input has sensor limit checking, open circuit detection, dc bias autonulling, and excessive dc bias detection. Alarms are generated for these diagnostics.
  
  
  
  

Details of the individual diagnostics are available in the ToolboxST^* application. The diagnostic signals can be individually reset with RESET DIA if they go healthy.

UCCA LEDs

STAT LED (Reserved)

IONet-- ETHERNET –

ON LED

Green = Controller online and running application code

IONet Ethernet LEDs

Green = 100 base TX and full duplex

Blinking = Activity

OT LED (Reserved)

Diag LED

Solid Red = Diagnostic available

DC LED

Green = Designated Controller

UDH Ethernet Status LEDs

Active (Blinking = Active)

Speed (Yellow = 10 BaseT)

(Green = 100 BaseTX)

UDH ETHERNET (UDH)

Primary Ethernet port for Unit Data

Highway communication (ToolboxST)

COM1  RS232 C Port for Initial Controller Setup

COM 2 RS-232 C Port Reserved

Status LEDs

System: When off, CPU is ready

IDE: Flash disk Activity

Power: Lights when power is applied

Reset: Lights during reset condition

MEZZANINE CARD

COM

Configuration

Note  The following information is extracted from the ToolboxST application and represents a sample of the configuration information for this board. Refer to the actual configuration file within the ToolboxST application for specific information.

Caution

If the CCSA In JB1000 is used, set InputUse and the terminal board jumpers to CCSA regardless of the transducer manufacturer. Damage to the CCSA may occur if the PCB jumper setting is used on the terminal board.

PAMB Board Points

SAMB Acoustic Monitoring Terminal Board

Refer to the chapter, PAMC Acoustic Monitoring Input Module, the section, SAMB Acoustic Monitoring Terminal Board.

PAMC Acoustic Monitoring Input Module

Acoustic Monitoring Input (PAMC)

Functional Description

The Acoustic Monitoring Input (PAMC) module supports combustion dynamics for heavy-duty gas turbines. The PAMC module includes the IS210BAPAH1A Analog Processor (BAPA) and the Acoustic Monitoring (SAMB) terminal board grouped together as an application subassembly, and the IS220UCSAH1A standalone processor module.

The UCSA mounts as a standalone LAN module and serves as the PAMC processing engine. The UCSA was selected for acoustic monitoring because it provides the additional processing capacity required for the fast Fourier transform (FFT) analysis, sorting function, sensor diagnostics, and so forth. The UCSA accepts dynamic pressure data from the SAMB. The analog signal is conditioned to remove dc bias and amplify ac content (to maximize resolution) before it is digitized by an analog-to-digital (A/D) converter. A field programmable gate array (FPGA) sequences, digitizes, and filters the dynamic pressure signals and controls the high-speed serial link (HSSL) protocol for the Ethernet link between the BAPA and the UCSA.

Two versions of the Acoustic Monitoring system are offered, as follows:

Duplex Acoustic Monitoring System (323A4747WCP4) - The SAMB fans all 18 inputs to each BAPA. The BAPA 1 (left) communicates with the UCSA connected to IONet R. The BAPA 2 (right) communicates with the UCSA connected to IONet S. The controller's application code votes which PAMC data to use, based on the signal health.

Low-Noise Cable

Pressure Sensor

Turbine Combustor (max. of 18)

CDIS Constant Current Charge Amps(s)

Cable Twisted & Shield

Acoustic Monitoring

PWR

ATTN

LINK

FLASH

DIAG

BOOT

USB

COM

To Controller

PAMC connects to either a PCB-based CDIS CCCA or Encore-based CCSA

Mark VIe Duplex PAMC (323A4747WCP4)

Simplex Acoustic Monitoring System          (323A4747WCP3) - Controller application code is not required to vote signals from the PAMC. The PAMC connects to either a PCB-based CDIS CCCA or Encore-based CCSA.

Installation

The installation procedures in this document only cover the addition of the PAMC I/O module into a Mark* VIe control system without using the PAMC signal space inputs. A qualified GE technician must install the PAMC signal space inputs.

Attention

If the configuration being downloaded contains I/O packs with different module IDs than the configuration currently running, the download may install incorrect firmware to some I/O packs. If this occurs, make sure the controller is running the new configuration, restart the entire system, and then start the ToolboxST* Download Wizard again.

Low-Noise Cable

Pressure Sensor

Turbine Combustor (max. of 18)

Charge Converter Signal Amplifier (CCSA)

Cable Twister & Shield

(open)

Acoustic Monitoring

PWR

ATTN

LINK

POWER

BOOT

ONLINE

FLASH

DIAG

IONet to the Controller

Mark VIe Simplex PAMC (323A4747WCP3)

Adding a PAMC Module

• To add a PAMC

1. From the Mark VIe Component Editor,click the Hardware tab.
   
   
   1. From the Tree View, right-click the Distributed I/O item and select Add Module. The Add Module Wizard displays.
   
   

Select Simplex

Select PAMC as module type.

Click Next.

Click the Release Notes button to view additional information about the currently selected module version.

To ensure that hardware failures are identified and corrected prior to controller system operation, it is highly recommended that the Module Required check box be selected. If it is, the module must be present and functioning for the controller to go online.

Adding a SAMB Terminal Board

• To add a SAMB

1.          From the Component Editor, click the Hardware tab.

From the Tree View, right-click the Port_S1 item, then select Attach and SAMB.

2.            The Configure Sub-Assembly SAMB dialog box displays.

After sending Build and Download commands to the controller, click this button to retrieve the Bar Code.

Note          Additional attachments cannot be added to other ports.

3.      Enter the TB Connector that the BAPA is plugged into and the Bar Code of the SAMB. The bar code is located underneath the cover plate over the JB4 connector if no BAPA is plugged into this connector. If a BAPA is plugged into JB4, remove this BAPA to view the bar code or use the bar code retrieval method from step two.

IONet Setup

• To configure the PAMC for IONet Communication

The PAMC's UCSA must be configured with a TCP/IP address prior to connecting to the IONet Ethernet.

1.    Install and configure a serial connection to the COM port on the UCSA. A RJ-45 to DB9 adapter is required along with an Ethernet cable for the serial connection. The adapter part number is 342A4944P1. The following figure displays the pin definition of the UCSx RJ-45 to the COM port adapter.

GND--

White/Orange

Orange

White/Green

Blue

White Blue

Green

White/Brown

Brown

Converter

Grey

Red

Brown

Black

Yellow

Orange

Female

GND

2.            Use the ToolboxST application to configure the PAMC.

From the Hardware tab Tree View, right-click the PAMC module and select Setup

Click Next to continue.

Click Next to continue.

Click Next to continue.

The next wizard screen displays the progress of the connection. When it is complete click Finish.

Operation

The PAMC includes the following features.

•              Signal conditioning for up to 18 combustion dynamic pressure inputs:

-         GE Energy Charge-Converter Signal Amplifier (CCSA) or PCB Piezotronics^® Charge Amplifier for heavy-duty turbines are supported

-         Differential inputs and adjustable gains

-         Fast synchronous-sampled A/D with 16x over-sampling

-         FPGA pre-processor with finite impulse response (FIR) filters

-         Open wire detection

•              Analysis capability per channel:

-         Windowed FFT analysis

-         Rolling average per bin

-         50/60 Hz rejection filters

-         Sort function providing peak pressure amplitude for six different frequency bands

-         Maximum peak detect for each frequency band

-         Average channel peak-to-peak amplitudes per frequency band

-         Alarm detection if peak-to-peak amplitude exceeds configurable level for each frequency band

-         List capture for all 18 channels if alarm is detected or user requests capture

-          

UCSA Processor

The IS200UCSAH1A processor has the following features:

• High-speed processor with random access memory (RAM) and flash memory
  
  
  
  • Two fully-independent 10/100 Ethernet ports with connectors Enet1 and Enet2 for connecting to the main controllers' IONet ports.
  
  
  • Three fully-independent high-speed serial link ports with connectors R/SL1, S/SL2, T/SL3. Only R/SL1 is used in the PAMC for connecting to a IS210BAPAH1A analog processor board.
  
  
  • One universal asynchronous receiver-transmitter (UART) type serial port with RJ-45 connector
  
  
  • Hardware watchdog timer and reset circuit
  
  
  • Status-indication LEDs
  
  
  • Electronic ID
  
  
  • CompactFlash^® support
  
  
  
  

The UCSA connects to the BAPA through the R/SL1 high speed serial link (HSSL) interface. The PAMC is designed so that the UCSA and the BAPA can be located in different locations (up to 100 meters of high speed serial link cable length). Each module can be powered independently. At power up, the BAPA waits for the UCSA to initiate communications. After communication is established, the application FPGA is programmed.

The processor application code contains the logic to allow a UCSA to operate on one or two IONet inputs. When using two IONet inputs, both network paths are active at all times. A failure of either network does not disturb I/O pack operation and is indicated through the working network connection. This arrangement is more tolerant of faults than a classic hot-backup system in which the second port is only used after a primary port failure is detected. The Ethernet ports on the UCSA auto-negotiate between 10 and 100 mbps speed, and between half-duplex and full-duplex operation.

BAPA Analog Processor

The analog processor includes the following features:

•      Eighteen analog signal-conditioning channels

-         Differential inputs

-         Adjustable gains of 1x, 2x, 4x, and 8x

-         Dc bias nulling

-         Multiplexer to bypass signal input and apply test signal

-         Anti-alias filters to support 5 kHz bandwidth

•      Twenty-four A/D input channels

-         Six channels per converter

-         16-bit converter

•      Application FPGA

-         A/D converter control

-         D/A converter control

-         Eighteen channels of FIR filtering

-         Configuration registers

-         HSSL control

•      Boots FPGA with programmable read-only memory (PROM)

-         Bootstrap function

-         TX / RX mrm-MACs

-         PHY sync

•      PHY0 and PHY1 physical Ethernet layers

•      Power supplies

-         P28 input

-         P15andN15outputs

-         P5 output

-         3.3 V, 2.5 V, and 1.2 V outputs