An Intelligent Proportional Valve with Health Status Indication

Abstract

An intelligent proportional valve with health status indication, including proportional valve body, control signal input channel, spool position feedback channel, acquisition unit, calculation unit, output unit, setting unit, alarm indicator light and buzzer, health status LED group. It is suitable for control systems that use proportional valves as electro-hydraulic conversion units to replace conventional proportional valves. During the operation of the system, it monitors its own proportional valve electrical control signals and feedback signals in real time, and uses the proportional valve health status calculation method , taking the cycle of the proportional valve oscillating current as the cycle, calculate the proportional valve health sign signal and its change rate in real time, complete the real-time diagnosis of its own health status, and indicate its own health status in real time. When there is a trend, it will alarm in time to remind the operation and maintenance personnel to replace and maintain, so as to avoid adverse effects on the system operation and ensure the safe and stable operation of the system.

Description

technical field [0001] The invention relates to the technical field of proportional valves, in particular to an intelligent proportional valve with health status indication. Background technique [0002] Proportional valves are widely used in industrial automation control, and are often a crucial key link in the control system. The health status of the proportional valve determines whether the system can operate safely and stably, so it should be paid attention to. At present, there is no mature intelligent proportional valve with a proportional valve health status indicator, and only an instrumented proportional valve controller product with a fault alarm function is disclosed. The Chinese patent "An Instrument Type Proportional Valve Controller with Fault Alarm Function" (ZL: 201821194040.4) describes an instrument type proportional valve controller with fault alarm function, which has the following disadvantages: [0003] ①. It adopts a simple proportional valve fault s...

AI Technical Summary

Problems solved by technology

[0003] ①. It adopts a simple proportional valve fault state diagnosis method, which simply compares the deviation between the theoretical amplified value of the current input by the proportional valve and the amplified actual current value, and performs fault analysis and judgment according to the set deviation rate. It can diagnose the failure of the proportional valve, but cannot intelligently diagnose the performance degradation of the proportional valve or the precursor or trend of failure, and cannot help the operation and maintenance personnel to realize the preventive maintenance and repair of the proportional valve

[0004] ②, its fault diagnosis algorithm is too simple, only collecting the theoretical amplification value of the current input by the proportional valve and the actual current value after amplification for deviation comparison

However, there is a physical hysteresis effect between the amplified actual current value and the current input by the proportional valve through an amplifier, and the difference between the two must exist, especially when the current input by the proportional valve has a step change. The hysteresis effect of the final actual current value is more prominent, and the difference between the two is bound to be larger. This kind of working condition will inevitably affect and interfere with the difference between the current theoretical amplification value input by the proportional valve and the enlarged actual current value. method for fault diagnosis accuracy

Considering the influence of this working condition, the deviation rate of the manual setting criterion is often set relatively large. If the deviation rate is set too high, the criterion will be too harsh and fail, the accuracy of fault diagnosis will decrease, and faults will be easily missed.

If the deviation rate is reduced, the false alarm rate will increase

It can be seen that this simple criterion has a low correlation rate with faults, fault feature identification is not accurate, and fault diagnosis cannot be made accurately.

[0005] ③. It only has the function of alarm indicator light, and the indicator light is not enough to attract the attention of operation and maintenance personnel

[0006] ④. It can only qualitatively alarm, but cannot quantitatively indicate the health status level of the proportional valve

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