Fast flow control valve group and control method based on pwm and pcm technology

Abstract

The invention relates to a fast flow control valve group based on PWM and PCM technology. A plurality of parallel throttling pipelines are arranged in the main pipeline, and a proportional switching valve connected with a programmable logic controller is arranged on each throttling pipeline. The control method includes the following steps: setting the opening area of ​​the proportional switching valve of each throttling pipeline to double clockwise in sequence; the programmable logic controller converts the throttling set value of the main pipeline into binary code, After optimizing the order of the throttling pipelines, the binary coded digits are converted into pulse signals to control the on-off of the cut-off valves set in each throttling pipeline. The parallel throttling pipelines of the present invention are arranged circularly with the axis of the main pipe as the center, instead of being arranged in parallel on the same plane, eliminating the difference in pipe resistance between the inlets of each throttling pipeline; and combining the PWM valve proportional control technology with the traditional The combination of PCM gas force control technology realizes the fast and accurate flow adjustment of large flow gas.

Description

technical field [0001] The invention relates to a fast flow control valve group and its control method, in particular to a fast flow control valve group and its control method based on PWM and PCM technology. Background technique [0002] The commonly used gas flow regulating device in the pipeline is a pressure stabilizing valve or a regulating valve. The former integrates a self-control mechanism, changes the valve outlet diameter according to the set threshold, and has a fast response speed, but the diameter is small, and is only suitable for small flow gas control; the latter realizes the valve opening change through the action of an external electrical signal, and the range of diameters can be selected. It is suitable for large-flow gas control, but the valve response speed is slow, there is serious dead zone and hysteresis nonlinearity, and it is not suitable for fast control. It can be seen that when a single valve is used for gas flow control, there is mutual restri...

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Problems solved by technology

However, there are still some deficiencies in PCM flow control technology: (1) The calibers of the throttle pipes are usually different, resulting in differences in the pipe resistance loss generated by the airflow in each pipe, so that the equivalent throttle area is not 2 times proportional; (2) ) In the throttling pipeline, there are essentially two throttling devices, the throttling plate hole and the switch valve, which makes it difficult to form a 2-fold equivalence relationship in the actual throttling pipeline area distribution; (3) the throttling plate hole area is fixed, The maximum throttling area of ​​the entire gas pipeline is also fixed, the entire device is only suitable for one working condition, and the reusability is poor

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