scope:

Scope and Field of Application

The package of Guidelines VDI/VDE 3501 to 3506 contains instructions on the proper design of control circuits for steam generators in conventional power stations. Each of them are independent Guidelines, the Contents of which are nonetheless largely coordinated. A description of the control system is followed by the formulation of the control task; this is followed by a section containing descriptions of suitable configurations for the control circuits, with a further section devoted to an examination of the measuring equipment and actuators necessary for realisation of the control unit.

The adjacent Guidelines VDI/VDE 3500, 3507, and 3508 refer to the complete power Station. Although the findings and experiences contained in the Guidelines are widely known and recognised, they have not previously been assembled in this fashion.

The terms and notations used correspond to the definitions and symbols of Standards DIN 19227 "Symbols and distinguishing signs for process Instrumentation and control", DIN 2481 "Thermal power plants" and ISO 3511/3 "Process measurement control functions and instrumentation - Symbolic representation". The scope of application of this Guideline is restricted to temperature control systems in power stations in which superheated steam is controlled at a desired tar¬ get temperature using steam-side control interventions, such as, for example, spray coolers or heat exchangers, or flue gas-side control interventions such as flue gas reflux. Steam-to-steam heat exchanger Units are not dealt with in this Guideline.