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- Automotive Anti-Collision Alert System (ACS) by Distance Monitoring
- Advanced Process Controller (APC) {Steam Plants}
- Consortium 11 By Visvesvaraya National Institute of Technology (VNIT) 15-16 Jan 2011
- need help
- Google logo today
- Thin-walled pressure
- A great start!!!!
- Mobile OS and Plat form
- The "Next Generation tools" from Proceq have arrived in Asia
- wye delta combination of forwrad revers connection
- Pen stylus next chapter for table productivity?
- Final Year Project Ideas
- Aricent is hiring
| Automotive Anti-Collision Alert System (ACS) by Distance Monitoring Posted: 23 Dec 2010 11:07 AM PST this is my title for my project : Automotive Anti-Collision Alert System (ACS) by Distance Monitoring this project is about measuring the safe distance that will varied according to the speed of the car. If the rear car exceeds the safe distance between the two cars at a particular speed, the front car will trigger a warning system by flashing LEDs to the rear driver as well as produce a beeping sound to alert the front driver that a car is approaching his car at a close distance..do anybody has ideas how to develop this type of project?I really need help to start develop this project..many thanks. |
| Advanced Process Controller (APC) {Steam Plants} Posted: 23 Dec 2010 11:06 AM PST "Control of Steam Power Plant is very big job need Care to fulfill the appropriate degree of stability and dependability for such this big system " In many countries, plants have to fulfill specific requirements of the electrical grid (such as frequency control, dispatch control, automatic generation control (AGC), and so on) and are paid accordingly, based on their performance. Under these circumstances, it is extremely important for the plant to have the capability to precisely follow the provided load set point. Within the plant, proper coordination of the turbine and boiler operation is of extraordinary importance. This coordination is realized by the unit control, which generates set points for the boiler and turbine to keep the desired load set point while maintaining the desired operating pressures and temperatures. Control System Basics One of the most critical control circuits is the control of the main steam pressure. Steam pressure is controlled by adjusting the fuel flow to the boiler in the case of a power-controlled turbine. Therefore, controlling fuel flow originates from the non-self-stable control circuit (Figure 1).  Figure 1 Let’s assume that the load set point of the turbine PG,SP shown in Figure 1, as well as the fuel flow to the boiler, is constant and the boiler load is somewhat higher than the set point of the electrical load. In this case, the boiler will produce more steam than the turbine consumes. Therefore, the main steam pressure PMS will increase until the high-pressure (HP) bypass or the safety valves open. Under this operating scenario, this control circuit is not self-stable. The pressure will only be stable at one single point, namely, where the boiler load exactly matches the turbine load. But pressure starts to drift away from its set point with every minor system disturbance. Furthermore, there is a time delay of several minutes between the operation of the actuator (fuel flow) and the controlled variable (main steam pressure) response. A very responsive control system design is required to quickly sense and respond to accurately control steam pressure. Highly sophisticated control concepts are needed to achieve very good control performance in any steam plant. However, translating these control concepts into a functioning and reliable system usually requires very sophisticated and complex control loops that are extremely labor-intensive to commission and maintain. In many cases, model-based control logic is used in the plant controls, and during commissioning, actual unit performance tests are required in order to measure the static and dynamic response of the unit and determine the corresponding model parameters. These tests can be time-consuming and very expensive. Also, the more accurate the control performance targets, the more detailed the models used in the control structure must be. But as more detailed and accurate parameters are required, even more tests become necessary, and the overall commissioning process thus becomes more and more expensive. Compounding the testing dilemma, when coordinating tests with the load dispatcher, the unit must be operated at a specific load and might not be operated at the most beneficial load point required to tune the controls. There are situations under which a conventional control system design cannot respond to system changes. For example, if the dynamic response of the boiler changes over time, control performance will degrade. The simple proportional, integral, derivative (PID)-correction controller has to take corrective actions more and more frequently due to the model inaccuracies. These inaccuracies compound and will eventually produce a negative effect on the unit’s stability and flexibility. As a solution to these shortcomings, Siemens Energy has developed an advanced process controller (APC) for controlling the main steam pressure of a steam power plant by adjusting the fuel flow as an actuator. One major advantage of this controller is that it requires much less controls tuning and lower operating during commissioning. In fact, there are only two major parameters that need to be adjusted. When compared to a conventional controller, the commissioning time can be reduced by more than half. The remainder of this article describes actual test results taken from a steam plant start-up that validates our claims. The Conventional Steam Control Concept Figure 2 illustrates the typical way of controlling main steam pressure with a model-based feed-forward approach by adjusting the fuel mass flow. During load changes—load ramps as well as frequency disturbances—the required dynamic change in fuel flow, including necessary overtiring, is calculated by the incorporated models to achieve the desired dynamic unit response. The set point for pressure is dynamically adjusted in accordance with the calculated fuel demand so that the PID pressure controller will have no control deviation in the event of undisturbed unit operation. The pressure controller only intervenes in the event of disturbances.  Figure 2 Using a stabilization structure, the load set point of the turbine controller is adjusted as a function of the control pressure deviation from set point. For example, in the event of a main steam pressure that is too low, the turbine supports the pressure by throttling the HP valves. In this way, the boiler becomes an actuator for a self-stable control plant. However, every pressure control deviation that occurs will also result in a deviation of the electrical power from its set point. The dynamic response of the power plant that was achieved with the model-based feed-forward structure is illustrated in Figures 3 and 4. The rate of change for the load ramp illustrated in Figure 4 was approximately 4.5% per minute. Observe in these figures that the unit is stable and accurately follows its load set point with no major over- or undershoot. This demonstrates that very good control performance can be achieved with the model-based feed-forward structure. The power plant with the SPPA-P3000 control structure was truly a demanding benchmark for testing the APC-based unit control structure.  Figure 3 Steady state case  Figure 4 load ramp case. The performance that can be achieved with a conventional unit control can be accurate, stable, and reproducible as long as the calculated trends for the fuel mass flow and main steam pressure are close to the real dynamic response of the boiler. Therefore, it is important that this data is incorporated into the controls system during commissioning to ensure that the dynamic model parameters are accurately determined. Determination of the model parameters must be carried out separately for load ramps, frequency disturbances, pressure set point changes, and so on. A great deal of testing may be required during commissioning to determine these model parameters. With respect to the trends shown in Figure 4, we should note that German power plant units are typically operated with a natural S-curve for normal load ramps. This means that with an increasing load set point, the fuel flow is increased. The load set point of the turbine is increased once the additional fuel flow results in increased steam production. Therefore, there is no initial pressure drop, and the boiler can be operated smoothly. The APC-based unit control concept is applicable in the same way for unit operation with undelayed load ramps. Advantages of an Advanced Process Controller  Figure 5 The APC-based unit control concept for main steam pressure control Figure 5 can be differentiated from the conventional unit control approach in several important ways:
APC Control Delivers Tighter, Faster Performance In Figure 6, the control performance during steady state operation can be seen. Compare this level of performance with that shown in Figure 3 and it’s obvious that the main steam pressure is as stable as it was before, and the pressure control deviations are quite similar. However, with the APC there was no modification of the turbine set point as a function of the pressure control deviation, the electrical load followed its set point with a very high accuracy, and the corresponding control deviation was practically zero. From a load control standpoint, control performance was enhanced compared to the former control structure. Figure 7 shows the control deviation for a load increase at a rate of approx. 4.5% per minute. Again, there was virtually no control deviation for the electrical load. Control performance, which was already very good before Figure 4, was further improved. The APC not only stabilized the main steam pressure but also handled the pressure increase experienced because the unit was operated in sliding pressure mode, as the higher load set point requires a higher main steam pressure. Comparing the test data with that in Figure 4 shows that the pressure increase was performed slower than before. However, this was not a question of the different control concepts used but a question of how quickly the commissioning engineer wanted the pressure set point to increase. When the APC structure was commissioned, it was decided to perform pressure changes slowly to allow smooth boiler operation. Figure 8 illustrates how the unit responded when the load set point was increased and then reduced. The load change rate was approximately 5% per minute. The APC was able to quickly stabilize pressure, and the load followed its set point with a very high accuracy.  Figure 6  Figure 7  Figure 8 ------------------------------------------------------------------------------ BIG THANKS TO MR/ Dipl-Ing. Bernd Lamb is a project engineer in the Process Optimization group of Siemens Energy’s Fossil Power Generation Division |
| Consortium 11 By Visvesvaraya National Institute of Technology (VNIT) 15-16 Jan 2011 Posted: 23 Dec 2010 10:24 AM PST A great idea starts in a great mind. However the successful execution of this idea takes a lot of people – and managing so many people in turn takes just one person – a great ENTREPRENEUR. There is one within us too and here's a festival to let it emerge to the fore. Presenting a brand new CONSORTIUM '11. Visvesvaraya National Institiute of Technology, Nagpur has always been on the forefront of technological advancements in various fields of science and engineering, thus fulfilling its primary aim. But, being a dynamic unit of a changing era it has also kept pace with time. In its endeavor to excel to further heights, it has the country's only management and business festival – CONSORTIUM – in a technological institute. So get ready to immerse yourself into this ceaseless world of money and enjoy the pleasures of profits while sharing the satisfaction of a successful strategy. All this and so much more at CONSORTIUM'11 await you. Events at Consortium 2011 are: Corporate Corpwars HR Management MaxX-Pro Sosyal Manus Kaizen Radio FM Crowd Magnet Entrepreneur Advertising Carnama EPL Manager B-Strike 1.6 Informals Traditional 24-Crisis Management Sansad Bizmantra Online Events E-Summit B Plan Choti Si Asha For more information, visit : CONSORTIUM '11 |
| Posted: 23 Dec 2010 06:20 AM PST i had noted a problem in my friends laptop actually he called to me to check that problem is he is using os as xp professional sp3 he told that he installed that os in showroom they made 30gp for os disk and other disks has higher space anyway the problem is it is showing no space in local disk and is neither uninstalling any software installed in it now my question is is there any way to solve this problem with formatting???? |
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| Posted: 23 Dec 2010 04:39 AM PST Can somebody help me about this question? :)It's an assignment given to us this Christmas vacation. Here is the question: The tank is fabricated from 1/4 in. steel plate. Calculate the maximum circumferential stress caused by an internal pressure of 200psi. The tank has a shape of ellipse where a=5in. and b=3in. Please show your solution. |
| Posted: 23 Dec 2010 02:58 AM PST hello everyone!!!!I'm maraia flor ,a civil engineering student from Philippines. This is a really great site to all engineers!!!! I'm looking forward of broadening my knowledge by the help of this site and all of you guys out there... |
| Posted: 23 Dec 2010 02:31 AM PST What is the difference between mobile OS and PlatForm? Which is the plat form used by nokia N series phones? Please reply me. |
| The "Next Generation tools" from Proceq have arrived in Asia Posted: 23 Dec 2010 12:12 AM PST Proceq extends services to Asian market. What I personally like about these next generation tools is that they combine both electronic display and advanced mechanics Check them out < link removed. No advertisements please> do you guys consider their tools as "the next generation"? |
| wye delta combination of forwrad revers connection Posted: 22 Dec 2010 11:47 PM PST Hi, me i know the installation and schematic diagram of wye delta and forward revers connection. |
| Pen stylus next chapter for table productivity? Posted: 22 Dec 2010 08:42 PM PST You thought that with capacitive touchscreens, the world would be rid of pesky stylus pens for good, didn't you? Well N-trig, a company whose tech has been used on a number of Windows computing products, is eyeing the Android tablet platform as the next venue for pen input, which would include utilizing a stylus for inking, drawing, and digital note taking. N-trig is arguing that companies can differentiate itself from competitors with a stylus, extending tablet products beyond just content consumption devices will give companies an edge–a strategy that HP has used on its HP Slate 500 Windows tablet, which was released with an active digitizer pen and geared towards enterprise customers. N-trig is saying that adding a pen can cost the company around $50, but would offer improved accuracy and more versatility to the end user. Another company that's looking at this space is Adobe. Though the company is taking a wait and see approach as to what types of software that it may release, and when, the prospect is there for more a professional software suite or app–like a scaled down version of Photoshop–that would allow for better photo manipulation thanks to the accuracy of pen input. Adobe Vice President Michael Gough says, "Adobe will follow that, I think, just as much as they lead it. It all depends when the devices are in people's hands." A more productive tablet environment would offer the company more business as it could potentially port some of its best-selling titles from Creative Suite to consumer tablets. Consumer tablets, like the iPad, are more geared at content consumption, which doesn't offer Adobe much business with consumers.- Via UberGizmo  |
| Posted: 22 Dec 2010 05:46 PM PST Hi dear Engineers! I am currently looking for ideas for my Final Year Degree Project. I have ran out of ideas at the moment as most of my ideas are being rejected by the faculty. I need some innovative ideas in Mechanical engineering project. Please help me guys. Alternatively you all can email me at pejanth@hotmail.com if there is any ideas. Thank you. |
| Posted: 22 Dec 2010 09:51 AM PST hey guys aricent is hiring for 2009,10 ,11 so hurry :) Durgajobs.com (IT Jobs, Government Jobs, Bank Jobs) |
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