Operation of esp. control valve with soft seal and continuous drive

摘要

The valve (8) is operated by the effective value (yeff) of the output from a controller (9) whose input parameters are a cycle duration (ZL), a pulse base (IB) and peak (IS), a limit of seal closure (DS), and gradients (GS,GF) of leading and trailing edges. At low throughput values for which the soft seal is not opened, the effective control signal has a duration within which the cross-section is opened and, averaged over time, is approximately linear w.r.t. the flow or deg. of opening.