| 摘要 |
The installation has gas boilers, and gas-fired co-generation units connected to a metering unit which measures the quantity of gas consumed, and based on this, a gas feed unit is controlled to regulate the combustion process.- DETAILED DESCRIPTION - A typical installation has heat requirements (4) met by several gas boilers (10,12,14), one of which (12) can also operate on fuel oil, supplemented by the thermal output of gas-fired cogeneration units (20,22) whose electrical output is sold to a public utility under high priority terms. All units are controlled by a central unit including a processor (50), tactile response screen (52), and a modem (54) giving remote control and alarm facilities over a telephone line (RTC). Gas consumption values, corrected (7) for pressure, temperature, etc., are input via a data link (8), with emergency back-up (9) from the impulsing meter (6). The processor must ensure that the gas consumption in any 24th period does not exceed a figure agreed with the supplying utility, as this entails substantial penalties. Instant values are checked against an appropriate consumption/time curve, and boiler outputs reduced if necessary. Opt., dual-fuel units are transferred to oil firing. Reduction in cogeneration is avoided. The controller also applies priority criteria in bringing units on- and off-stream. A portable terminal (60) allows local staff to check conditions |
