Pump Controller
Design Report
Team Number
May06-12
Client
Viking Pump
Advisors
Nicola Elia
Team Members
Dan Paulsen - Team Leader
John Taylor - Communications Coordinator
Dwayne Stammer
Francois Munyakazi
Clifford Pinsent Jr.
Report Disclaimer Notice
DISCLAIMER: This document was developed as part of the requirements of an electrical and computer engineering course at IowaStateUniversity, Ames, Iowa. This document does not constitute a professional engineering. Although the information is intended design or to be accurate, the associated students, faculty and Iowa State University make no claims, promises, or guarantees about the accuracy, completeness, quality or adequacy of the information. The user of this document shall ensure that any such use does not violate any laws with regard to professional licensing and certification requirements. This use includes any work resulting from this student-prepared document that is required to be under the responsible charge of a licensed engineer. This document is copyrighted by the students who produced this document and the associated faculty advisors. No part may be reproduced without the written permission of the senior design course coordinator.
Date Submitted
12/14/2005
1
Table of Contents
List of Figures
List of Tables
List of Definitions
Introduction
Executive Summary
Executive Summary
Acknowledgement
Acknowledgement
Problem Statement
Problem Statement
Operating Environment
Operating Environment
Intended Users
Intended Users
Intended Uses
Assumptions
Limitations
Expected End Product and Other Deliverables
Approach and Design Considerations
Design Objectives
Functional Requirements
Design Constraints
Technical approach Considerations
Testing Requirements Considerations
Detailed Design
Pre Existing Modules
Software Design
Hardware design
Estimated Resources and Schedules
Schedule
Closure Material
Client Information
Faculty Advisor Information
Student Team Information
Closing Summary
References
Closing Summary
List of Figures
Figure 1 – Whole Project Schematic
Figure 2 – Software Design Overview
Figure 3 – Data Hub to/from Pump Interface
Figure 4 – Data Hub to/from PC Communication Interface
Figure 5 – PC Communication to/from PC Interface
Figure 6 – Data Hub to/from Touch Screen GUI Interface
Figure 7 – Data Hub to/from Control Algorithm Interface
Figure 8 – Data Hub to/from Pulse Counter Interface
Figure 9 – Implemented Hardware Schematic
Figure 10 – Current to voltage conversion
Figure 11 – Voltage to current conversion
Figure 12 – Original Gantt Chart
Figure 13 – Revised Gantt Chart
Figure 14 – Deliverable Schedule
List of Tables
Table 1 – Required Parts List
Table 2 – Expected Personal Effort Requirements
Table 3 – Revised Personal Effort Requirements
Table 4 – Original Other Required Resource Requirements
Table 5 – Revised Other Required Resource Requirements
Table 6 – Original Expected Financial Requirements
Table 7 – Revised Expected Financial Requirements
List of Definitions
Flow meter: An instrument used to measure pressure, flow rate, and discharge rate of a liquid, vapor, or gas flowing in a pipe.
GUI: An abbreviation for graphical user interface.
I/O: An abbreviation for input/output.
Positive-displacement pump: A pump in which a measured quantity of liquid is entrapped in a space, its pressure rose, and then is delivered; for example, a reciprocating piston-cylinder or rotary-vane, gear, or lock mechanism.
Pressure transmitter: A device used by the pump to measure the inlet and outlet pressures.
RPM: an abbreviation for revolutions per minute. It is a measure of speed for spinning objects.
RTD: Resistance temperature detector; a metallic probe that measures temperature based upon its coefficient of resistivity.
Set point: the speed that a pump has to rotate in order to achieve a given flow or output pressure.
Specific gravity: the specific gravity of a substance is a comparison of its density to that of water.
Variable speed pump: A pump which allows the output velocity to be varied continuously.
Visco-elasticity: Property of a material which is viscous but which also exhibits certain elastic properties such as the ability to store energy of deformation, and in which the application of a stress gives rise to a strain that approaches its equilibrium value slowly.
Viscous: Having a relatively high resistance to flow
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Introduction
This document is intended to become define the basis design for senior design group May06-12. The group’s current problem, design, and development process will be defined in this document. Also this document will include the expected cost and schedule of the project.
Executive Summary
The goal of this project is to implement a control algorithm which will control the flow rate of a highly viscous material to within 0.25% of the desired flow rate. The algorithm will do so without measuring the actual flow rate by mechanical measurements. Also, a prototype controller will be constructed to control a pumping system using the control algorithm previously mentioned. Finally, a model of the pumping system will be created and delivered to the client.
A major goal of the project is to make the user interface efficient and friendly. The user interface will support security of the pump control from unqualified individual trying change the pump’s settings using the user interface. The ability to change such settings will require access to a key or password which will allow these changes. Moreover, the user interface will display the current configuration of the device, and the current status of the device. This will be done via a touch screen and onscreen keypad for easy entry of data and a user friendly understanding of the pump settings and configuration.
The flow manager will support all currently supported features as well as have support for add on features at a later time. A short list of new features such as remote configuration and control via a new pc based application which will communicate with the flow manager using a common 9-pin communications port. From this new application qualified users will be able to configure the flow manager, create and store profiles with will hold saved setting for a particular application.
Future features for the flow manager may include logging of the flow manager’s status history for viewing by the qualified personal.
The group will use unit testing to test for each part of the project before it is combined with the rest to ensure bug free software and circuitry.
Final testing of the product will ensure bug free software and hardware for the product before delivery to the client in May, 2006.
Acknowledgement
Viking Pump will provide a pumping test bed along with a set of flow equations on which to base the control algorithm. They have also granted permission to use their patented algorithm. Viking Pump will also provide a DC drive to supply power to a pump, and a box which to hold the flow manager components.
Problem Statement
One of Viking Pumps flagship products has been their flow manager which has led the market for pump controllers for many years. However the product was designed and built over twenty years ago and its design is behind the curve of modern technology and user ability. The flow manageris difficult to use and lacks the user friendliness that is common on today’s modern consumer environment. It has also become apparent to Viking that the parts which were used to implement the older pump control are no longer available. The client wants to implement the functionality of the original flow managerto a new and modern interface with the ability to expand functionality of the flow manager in the future. The old flow managersupports the regulation of volume of highly viscous fluids without using a mechanical means of measuring the flow. The control instead draws inputs from the liquid pressure on both sides of the pump along with the temperature of the liquid. Using these inputs along with the known parameters of the liquid a algorithm, which is supplied by Viking Pump, is used to calculate the how fast the pump must run to obtain the specified volume. The current flow managersetup can maintain a flow within .25% of a specified set point. The current flow manageralso supports other functionality including batch flow (Pumping a specified amount of volume) and the ability to adjust the flow in real-time to a voltage input with would specify the volume needed. The current flow manager also supports a PC connection via a common nine pin communication port. This port is used to read and write values to the flow manager that can not be changed using the current user interface.
The proposed solution to this problem is to exchange the current flow manager display with a new touch-screen display which will be code named flow manager2 (FM2) during development. The flow manager2 will support more methods of user input than the button press and eight segment display that the flow managercurrently has. The flow manager2 will include analog-to-digital (A/D) capability to read the inputs from the pump setup. Fflow manager2 will also have a digital-to-analog (D/A) capability to write outputs to the pump setup. These inputs and output will be unchanged from the current flow managersetup to make the new controller totally interchangeable with the all old setups. The FM2 will also support the communication port interface with will allow different types of user security and also different types of users to change the variables of the flow manager2. This will make the new PC interface more advanced than the old interface. The FM2 will support a profile saving system with will allow the user to select different setups without having the reprogram the FM2 for different types of liquid. Future abilities for the FM2 may include logging of the setup and the variables within the FM2 for viewing by users.
Operating Environment
The expected operating conditions for a final product will be in a factory, 40 – 120 degrees Fahrenheit. It will have to be durable enough to sustain normal factory conditions for the duration of its life. The controller will be stationary once installed and not subject to moving hazards. Also, since it will be designed to be used in a factory, it will not be subject to the changing weather conditions, except that of temperature.
Intended Users
The intended users for this product are people working in a factory environment. These users need to be able very accurately control the flow of a highly viscous fluid flowing through the pump with the FM2 is controlling. The intended user of the FM2 has a good working knowledge of the pump and the fluid which to be pumped. It is expected that the users will be able to read the operating manual for the FM2 and provide the necessary inputs to properly manage the system. A person with the proper training and technical knowledge of the variable speed pump and the sensors used will be required to properly install and setup the FM2.
Intended Uses
The intended use for the FM2 is to control the volume displaced by a positive displacement pump that is pumping a highly viscous fluid by varying the speed (RPM) of the pump. This will provide a constant output from the pump which is being controlled. It is expected that the pump will be used in a controlled environment where it may be exposed to extended periods of operation. The end product is not intended to be used on any type of pump that is not supported.
Assumptions
In order to complete the project some assumptions concerning the design and materials available have been made. These assumptions are:
Viking Pump will provide the information and support necessary to model the pump system and will provide a suitable pumping test bed.
The controller will receive measurements of inlet and outlet pressures, fluid temperature, and pump speed which are correct and in real time.
The controller will be configured by a user with knowledge of the parameters of the fluid being pumped.
The flow being controlled will not be a turbulent flow.
Viking Pump will provide funding for all necessary hardware which will be returned to Viking Pump at the end of the project.
The min/max pumping rates and min/max pressure values will not be a constant value, but, however, will be dependent on the application.
The device setup will have an abundant 120 volt power supply from which to use to power the FM2 itself and the pump it controls.
Limitations
There are some limitations to the design that must be met and cannot be changed. They are requirements put in place by the client, Viking Pump, and are as follows.
The FM2 must be able to operate in a real time environment which will provide the best quality control of the flow through the pump.
The algorithm implementation must be portable.
The controller solution must be economical.
The controller must be able to control instantaneously the actual flow within 0.25% of a specified point chosen by the user.
Expected End Product and Other Deliverables
A prototype FM2 for the pump system will be delivered to the client, Viking Pump. The FM2 will successfully control a variable-speed positive-displacement pump and provide accurate flow of highly viscous fluids. The FM2 will take use no more room than the current flow manager and will interface with the pump which it controls in exactly the same fashion as the current flow manager. The fully function FM2 will support a user interface using a new touch-screen which is built into the FM2 itself or using a new PC interface which can control the FM2 remotely using a standard nine-pin communication port. The prototype FM2 will be accompanied by the source code of the software, documentation of the design, project plan, and test results explaining both the design and use of the FM2.
Approach and Design Considerations
This section of the document will explain the approach used in the design of this FM2 and the considerations taken when developing a design for the FM2. This section of the design document will also explain the detailed design which came from this approach and considerations.
Design Objectives
The following is a list of objectives which the played a roll in the design of the FM2. These objectives were used to help improve the design of the FM2 and a design with meets there objectives will be picked as the primary design of the FM2.
- Future functionality -The design must incorporate the ability for the FM2 to expand in the future to such functionality as logging of the FM2’s status to a file to be read by the user for troubleshooting or reporting purposes.
- Simple design -The design must be intuitive to the project goals. This will require the design properly match and be configured to the project rather than a design which is geared for another purpose.
- Operating environment conditions - The design must take into account that the device is to be used in a factor setting where electromagnetic fields may be large and disrupt discrete voltage inputs and outputs.
- Interchangeable with previous setup - The design must use the existing inputs and outputs to control the current pump setup. A foreign setup will not be interchangeable with the current flow manager setups which Viking Pump already has in place and supports.
- Same size, similar weight -The design of the FM2 must fit in the box supplied by the client. A design which is larger will not meet the requirement of being interchangeable with the current system.
Functional Requirements
The following requirements where placed on the project by the client Viking Pump:
Accurate flow control – The end-product shall be able to control the flow of a given fluid under user-defined conditions of the application such as viscosity of the liquid or flow rate. Users shall be able to configure the system to maintain a set pressure or flow rate by varying pump speed.
Fast-processing – The end-product should be capable of processing information quickly enough to make the necessary changes in real time.
Able to interface with the required sensors – The controller needs to be able to receive and interpret inputs from the provided sensors (inlet and outlet pressure, temperature of fluid, and pump speed) and provide the necessary outputs to control the system and inform the users of the current state.
Store and interpret provided inputs – The prototype needs to be able to take user inputs such as the amount of liquid that should be pumped, the flow rate, and information about the viscosity of the liquid along with any other required information.
Provide a friendly user interface – The controller must provide an easy to use interface for configuration and status monitoring. The user should be able to easily set the pump’s operation data, such as fluid viscosity, as well as set the desired flow rate. The flow rate and other data should be readily accessible to the user.