Gas ratio valve control circuit

Abstract

There is a sort of gas proportional valve control circuit, and it is characterized in that: It changes the PWM control signal to the voltage signal by the low band filter circuit. After it is magnified by the linear operational amplifier circuit, it processes the comparison and blowup by the comparison circuit and the voltage of the current reactive circuit of the proportional valve current, and it controls the conduction and the close of the regulation pipe by the regulation control circuit, so it controls the current output of the fly-wheel diode and the proportional valve coil loop. It resolves the lack of the existing proportional valve beginning regulation and the control precision, and it increases the control precision of the gas proportional valve, also it increases the currency and the adaptability of the circuit control plate and so on.

Description

Technical field: [0001] The invention relates to a control circuit of a proportional valve for a gas appliance. Background technique: [0002] At present, household constant temperature gas water heaters and gas wall-hung boilers usually use gas proportional valves for constant temperature control. There are many structural forms of gas proportional valves, which can basically be divided into movable iron core electronic proportional adjustment type and electronic proportional adjustment with pressure servo. Type; two kinds of proportional valves must be initially adjusted to determine the maximum output and minimum output load. The former usually adopts the method of sampling and memorizing the proportional valve current at the maximum and minimum output load respectively, so that when the control is adjusted, the proportional valve current is fed back and compared to limit the PWM adjustment range. This method will greatly reduce the proportional valve current. The contro...

AI Technical Summary

Problems solved by technology

The former usually adopts the method of sampling and memorizing the proportional valve current at the maximum and minimum output load respectively, so that when the control is adjusted, the proportional valve current is fed back and compared to limit the PWM adjustment range. This method will greatly reduce the proportional valve current. control accuracy; the latter method is to fix the output voltage and adjust it mechanically, but when changing the gas type, the fixed output voltage must be changed; using the above two methods, the circuit cannot be applied to each other

Therefore, it will cause defects such as circuit versatility and poor adaptability to gas types. In order to overcome these defects, the gas proportional valve control circuit has been developed.

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