Static Control System

Static Control System

 

an automatic control system in which the error in the steady state is usually not equal to zero and depends on the load on the controlled system.

Figure 1. Block diagram of a single-loop static control system: (CS) controlled system, (CU) control unit, (MT) primary measuring transducer (sensor), (AC) static automatic controller, (CCG) control curve generator, (AM) actuating mechanism

Figure 1 shows a block diagram of a single-loop static control system consisting of a controlled system and a control unit. The latter consists of a measuring transducer, automatic controller, and actuating mechanism. The control action x2 (t) and external disturbances f(t) act on the controlled system. The controlled variable x(t) of the controlled system is converted by the measuring transducer into the signal x*(t); the signal is fed to the automatic controller, where it is compared with the given value of the control action g(t) to form the error signal μ(t) = g(t)−x*(t). Subsequently, the dependence of μ(t) on the control variable x1(t) of the automatic controller is obtained to form the control curve. For a proportional position action controller, x1 = kt, μ where kt is the coefficient of transmission (amplification) of the automatic controller.

Figure 2. A very simple static control system: (P,) inflow pipe, (G) gate valve, (L) lever system, (F) float, (V) vessel with liquid, (P,) outflow pipe

As a rule, static controllers are relatively simple and economical and have quick response times. These characteristics make them suitable for use in automatic control systems for industrial installations. Figure 2 shows a very simple static control system for regulating the level of a liquid in a vessel. If there is an increase in the loss of liquid, the liquid level in the vessel is reduced, the position of the float is altered, and the gate in the valve rises, increasing the inflow of liquid. The steady state is achieved when the loss of liquid is equal to the inflow, which corresponds to some level different from the original level.

REFERENCES

See references under AUTOMATIC CONTROL.

A. V. KOCHEROV

References in periodicals archive ?
Not only does the new 977CM Pulsed DC controller provide the first true closed loop static control system, but its design also incorporates a range of features that make it easier for the user to sustain optimum performance and extend the cleaning interval.
We'll soon introduce wireless communication capability, allowing our static control system status data to be viewed by enabled devices such as remote PCs or smart phones.
This intelligent static control system increases productivity and prevents material contamination, while providing a safer work environment.
The first quarter of the financial year saw Meech's facilities in Oxfordshire go through significant restructuring to accommodate separate build areas for its AC and DC static control systems, with the aim to increase production capability, as well as improve process flow and productivity.
Meech International has launched a new distance sensor and feedback system, the latest additions to the company's Hyperion range of static control systems.
Meech has announced the latest addition to its Hyperion range of static control systems, the 959IPS ionizing air curtain.
The whole system was powered by a standard 5kV power supply used in many static control systems.
Fortunately, there are new static control systems that allow for adjustability and feedback controls.
Exair, Cincinnati, OH, USA, offers multiple static control systems for the narrow web market.
Converting customers now can tap the worlds broadest line of technically advanced static control systems with just one call.
Likewise, static control systems that easily integrate into process PCs or PLCs provide greater control over production quality.