Advanced MD control algorithms
The advanced control algorithms of PantherQCS are a result of many years of paper machine control applications work by Panther. The knowledge base includes considerable observation of experienced machine tenders. The prediction algorithms match the mathematical material/energy balance to the machine, therefore, accurately representing actual running conditions.
The major multi-variable MD control packages include:
Virtual basis weight
This is a comprehensive material balance algorithm which continuously adjusts MD stock flow in response to detected trends in key input variables such as consistency, freeness, speed, paper width and total flow. The algorithm incorporates proprietary strategies for feed forward predictive weight, feed forward freeness, and scanner feedback. In formers/vats, stock ratio control is included. Operator set targets such as the basis weight and moisture are included.
Multi-variable moisture control
This algorithm sets optimal MD moisture using a combination of inputs including machine speed, steam and temperatures, along with cascade and feed back control schemes. Input variables include scanner moisture (min/max/avg), sheet temperature and machine speed. Targets include items such as moisture target, speed limits and ramp limits. Note: this algorithm interacts with Virtual Basis Weight to build a more comprehensive balance of the machine’s operation. The two algorithms are dependent on each other for ideal operation.
Automatic grade change & QuickChange
This algorithm moves the machine to the new operating conditions based on the next grade to be run. Inputs include the product/grade name and specifications, fiber stock ratios, stock flow, ramp time and limits, settle time and next grade quality targets/limits. The output is selectable between ramp with stock flow or ramp before stock flow. QuickChange is a subset operation that automatically accounts for a sheet break and recovery of on-spec products within one machine dead time period.
Advanced CD control algorithms
MD control strategy to provide a comprehensive interactive solution. The CD control package includes CD zone mapping, control algorithms, actuator decoupling, limit checks, manual or automatic actuator control, a full set of configuration parameters and event flags, and interactive simplified operator screens for the machine tender.
The CD control package can be applied to most actuated CD control systems, including slice lip, rewet showers, steam boxes and stock dilution.
Three variations of CD control are available depending upon machine requirements. These are:
Single profile: used to control a single actuator set for one profile quality variable (most common)
Ratio profile: used to split control between 2 actuator sets and 2 profile quality variables
Frequency split: used to split control between 2 actuators affecting one common profile variable
Panther CD control includes overlays whereby stored profiles can be overlaid on a current profile for easy CD troubleshooting purposes.
Complete actuator status and control is included for maximum operator usefulness of the CD control system.
PantherQCS operator station
The QCS Operator Station is a comprehensive software interface for paper machine control. The software includes dedicated screens for specific control such as MD weight targets, grade selection, and sensor calibration. It includes control loop interfaces, profile trending, process trending, graphical process views, alarm pages, scanner control, and dedicated reports. These dedicated screens are built by and for machine tenders as opposed to typical generic faceplate and graphics pages. They provide a direct and simplified view of machine controls and production as an experienced operator would prefer.
The QCS Operator runs on conventional PC hardware and operating systems over state-of-the-art Local Area Networks (LAN’s). All components are commercially available in the marketplace.
PantherQCS is comprised of a set of selected software and hardware modules as required by each individual machine and mill situation.
Panther integrates these modules into a complete system ready for installation and startup. Panther provides complete project services in support of these systems.
PantherQCS software includes:
- Base system
- Operator interfaces
- Control modules
- System reports
- Interface modules
PantherQCS hardware includes:
- Control I/O
- Sensor I/O
- Scanners and frames
Includes the core system database and the Product Target for grade setup. The base system is a required element which supports all the other selected modules.
OEM Bundle: A set of basic operating licenses required to run the software. This includes the Microsoft Operating System, Source Runtime, and SQL licenses.
Workstation modules are applications that interface the user to the paper machine to perform monitoring, control, adjustment, events and alarm response. Principle modules include:
Operator Station: Includes display, selection and manipulation for profiles, trends, process controls, alarms, sensor check, and scanner controls.
RemoteOperator: Same as Operator Station but no control outputs. Used by supervisors to monitor the machine.
Engineer: All functions of the Operator Station plus configuration and parameter setup.
Control modules perform automatic control of the paper machine based on application. The modules are assembled per control requirements. Both advanced and traditional control strategies are included. The control modules are assembled based on the type of machine, either Fourdrinier and vat former in both MD and CD categories.
Additional control applications address the stock approach area for the machine.
- Virtual basis weight
- Feed forward
- Multi-variable moisture
- Automatic grade change
- Quick change
- Headbox control
- Multi-former/vat ratio control
- Coater control
- CD basis weight slice and dilution
- CD moisture (steam box)
- CD moisture (rewet) (IR dryer)
- CD caliper
- Stock prep
- Coater kitchen
Report modules include fixed production reports of machine manufacturing activity.
- Shift/daily production
- Grade production
Interface modules are used to connect to existing equipment — like a PLC — that becomes part of the system. Other interfaces provide connections to external systems which store and process data.
The OPC Client is used to interface to PLC and DCS systems to collect and pass data as required for PantherQCS.
OSIsoft (PI) SDK Client
The OSI (PI) SDK Client is used to interface to the OSI PI system to send data and profile information when this is the preferred historian for archiving of profile and process data. This requires a copy of the OSIsoft PI DAP server or SDK interface for operation.
ProcessAnalyzer complements PantherQCS system. It allows the user to recall the QCS process and profile variables to evaluate (dry end) profile quality against wet-end process variables for cause-and-effect problems. For more effective coverage, a TestCentral lab system can add lab test data. All information is plotted on a single screen.
Panther furnished ProcessAnalyzer separately from Panther QCS measurement and control System as a project option.
Panther’s QCS Hardware
A set of five types of NEMA 12 environmentally hardened and office personal computers used by engineers, operators and PM supervisors. The quantity is project dependent. Project furnished workstation hardware is continuously upgraded with advances in technology, such as conversion from CRT to flat screen monitors. This assures the customer is receiving the latest technology for the job.
- Floor mount, environmental
- Small unit, environmental space limited
- Touch screen, environmental
- Touch screen, office
- Desktop, office
A set of 5 computer types are used for frame/sensor control, process control, database and applications, and remote service. Computers are selected based on the most recent modern technology and matched to the intended application. Typically, the database/application server is made redundant.
- Control computer
- Frame computer (one per frame)
- Database/application server
- Database/application backup server
- Remote access (diagnostic) computer
Panther provides standard, NEMA 12, and air conditioned cabinets as required to house system field electronics, such as process I/O, scanner controls, mill floor mounted workstations, and rack computers.
The newest ink jet and laser printers are furnished to produce desired hard copy reports and printouts.
Network switches are used to interconnect the system components and connect to the mill information network for external data access to the system.
The Control I/O is a compact PLC consisting of an assortment of plug-in modules, such as control modules, input modules, output modules and interface modules. The assembly is rack mounted in a control cabinet for machine floor installation, and comes in two sizes:
- Control I/O for 72 (bundled) points
- Control I/O for 144 (bundled) points
Sensor Hardware Package
The Sensor I/O is a compact PLC consisting of an assortment of plug-in modules which control the scanner frame, and interface the sensors to the system. The assembly is rack mounted in a control cabinet for machine floor installation.
Scanning sensors provide profile arrays on basic paper quality variables including basis weight, moisture and caliper. The sensors are incorporated into scanning frames and interfaced into the system via the sensor I/O packages. All versions are field-proven to provide accurate and repeatable quality measurement in harsh paper machine environments. Panther technical services select the correct sensor for the application.
Basis Weight Sensors
- Kr85 Krypton
- Sr90 Strontium
- Pm147 Promethium
- Infrared transmission
- Infrared reflection
- Microwave non-contacting DS-20
- Microwave non-contacting DS-115
- Stationary 5-pack
Panther’s QCS system includes a wide assortment of scanning frames. The correct version is selected by Panther technical services based on application requirements.
- Unibody O-Frame
- Unibody single-side
Legacy system upgrade packages are used to refurbish existing sensor and/or scanning systems. Frames in good working order receive new controllers, software, power supplies that extend the life of the frame. Upgrades may include retention or replacement of sensors depending on their health and ability to support Panther’s advance control. Commercially available parts are used to reduce long-term service costs and to help extend service.
- Scanner control upgrade
- Basis weight sensor control upgrade
- Moisture sensor upgrade
- Caliper sensor upgrade
- Frame upgrade
Panther’s QCS is supported by ProcessAnalyzer, TestCentral, and MillTools, a set of other production management programs to provide a complete integrated approach for paper mill production management.
Panther Systems supplies complete services from conception through startup to continuing long-term support for installed systems. Continuing services include Panther 24/7/365 HelpDesk management, system calibration, maintenance, radiological inspections, hardware architecture, software development, configuration, database administration and training.