Process Controller Essay Example | Topics and Well Written Essays - 250 words

Process Controller - Essay Example The most important of these requirements is safety. This is primary, in order to ensure the well being of the people in the plant and for its continued contribution to the economic development. The operating temperatures, pressures, concentrations, etc. should always be within allowable limits. Quality is also an important factor. A plant should be producing the desired amounts and quality of the final product. Moreover, the various types of equipments have constraints inherent to their operation. Such constraints should be satisfied throughout the operation of the plant. The plant must also conform to the market conditions that are the availability of raw materials and the demand of the final products. It should be as economical as possible in its utilisation of raw materials, energy, capital, and human labour, hence, operating at minimum cost and maximum profit, striking a right balance between both to give an optimal performance. Also, various federal and state laws may specify co nstraints on temperature, flow rates of effluents, etc. to be within certain limits, keeping environmental regulations in mind. (Stephanopoulos 3) All these requirements dictate the need for a good design, which is accomplished through proper selection of controllers, plant design parameters, etc. Different controllers have different effects on the response of the controlled process. The type of feedback controller to control the given process hence forms the first step of controller design. The second design question is â€Å"How do we select the best values for the adjustable parameters of the feedback controller chosen?† This is known as the Controller Tuning Problem. Various performance characteristics such as Overshoot, Rise time, Settling time, Decay ratio and frequency of oscillation of the transient could be used as the basic criteria, while designing. The designer must strike a subjective balance between the different