公开(公告)号：US20250004441A1

公开(公告)日：2025-01-02

申请号：US18754498

申请日：2024-06-26

Applicant: SAMSON AKTIENGESELLSCHAFT

Inventor： Christian Fiebiger ,  Andreas Fiebiger

IPC: G05B19/406

Abstract: A method is proposed for identifying the cause of oscillations in a cascaded control loop of a control valve in a controlled process plant, including the following steps: Setpoint value and actual value of the control valve are determined over time. The setpoint value and actual value are checked to see whether they exhibit a continuous oscillation. If an oscillation is detected, the amplitude and period duration are determined. If only the actual value or only the setpoint value oscillates, the period duration is compared with a characteristic period duration of the control valve. If the actual value and setpoint value oscillate, the amplitudes are compared with each other and/or the period duration is compared with a characteristic period duration of the control valve. The cause of the oscillations is identified from the comparisons. With this method, the cause of oscillations in a control loop of a control valve can be narrowed down so that the effort required for troubleshooting in the plant is reduced. Production downtimes can be minimized and costs avoided.

公开(公告)号：US20230400120A1

公开(公告)日：2023-12-14

申请号：US18207929

申请日：2023-06-09

Applicant: SAMSON AKTIENGESELLSCHAFT

Inventor： Andreas Fiebiger ,  Fausto Crespo Vidal

IPC: F16K37/00 ,  F16K31/12

CPC classification number: F16K37/0041 ,  F16K31/12

Abstract: A method for preventing control-induced oscillations in a valve with a pneumatic actuator and position control with an integrating component, including the following steps: Checking whether oscillations of the valve member occur by counting the zero crossings or extreme values of the control difference. If oscillations were detected, it is checked whether they result from oscillations of the set point. If not, the dead zone is increased and/or the gain parameter is decreased. If no oscillations were detected, it is checked whether wear in the drive has exceeded a predetermined measure. If so, the dead zone is decreased and/or the gain parameter is increased. In this way, oscillations caused by the I-component of the control can be detected and stopped. Further changes to the parameters are only made when friction is expected to have decreased due to wear.

公开(公告)号：US12241565B2

公开(公告)日：2025-03-04

申请号：US18207929

申请日：2023-06-09

Applicant: SAMSON AKTIENGESELLSCHAFT

Inventor： Andreas Fiebiger ,  Fausto Crespo Vidal

IPC: F16K37/00 ,  F15B5/00 ,  F15B9/03 ,  F15B19/00 ,  F15B21/08 ,  F16K31/12 ,  G05B11/42

Abstract: A method for preventing control-induced oscillations in a valve with a pneumatic actuator and position control with an integrating component, including the following steps: Checking whether oscillations of the valve member occur by counting the zero crossings or extreme values of the control difference. If oscillations were detected, it is checked whether they result from oscillations of the set point. If not, the dead zone is increased and/or the gain parameter is decreased. If no oscillations were detected, it is checked whether wear in the drive has exceeded a predetermined measure. If so, the dead zone is decreased and/or the gain parameter is increased. In this way, oscillations caused by the I-component of the control can be detected and stopped. Further changes to the parameters are only made when friction is expected to have decreased due to wear.

公开(公告)号：US20240255937A1

公开(公告)日：2024-08-01

申请号：US18566167

申请日：2022-05-16

Applicant: Samson Aktiengesellschaft

Inventor： Andreas Fiebiger ,  Christian Fiebiger ,  Tobias Boll

IPC: G05B23/02

CPC classification number: G05B23/0275 ,  G05B23/0224

Abstract: A method for diagnosing a control/regulating system of a process facility having an actuator for setting a process fluid, may include: providing a diagnostic database with assignment of multiple state causes to a respective set of specified system reference properties, where each system reference property is assigned a necessary condition; providing a test database with an assignment of different diagnostic tests for a specified system reference property; detecting an actual system property of the system; determining a first system reference property, the condition of which is satisfied by the actual system property; for at least one state cause with a set of specified system reference properties, for a second system reference property of the set, detecting whether the condition assigned to the second system reference is certain; and ascertaining a diagnostic test the second system reference property.