Working principle of electro-hydraulic directional valve
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2018-12-20
The current displacement conversion department of CSV9 and CSV9H electro-hydraulic converters is a dynamic coil force motor composed of permanent magnets, magnetic covers, inner and outer magnetic plates, dynamic coils, and springs. The hydraulic servo amplification department is a three channel slide valve control differential cylinder with direct position feedback, composed of a control valve core and a follow-up piston (see Figure 1 for details). The installation pattern is plate adjacent
3、 The shape and installation dimensions of CSV9 and CSV9H electro-hydraulic converters are shown in Figure 2 When reverse current is input to the moving coil, the moving coil and the control valve core move upwards, the lower throttle port is closed, and the upper throttle port is opened larger. The pressure oil returns through the T port, reducing the oil pressure in the upper chamber of the follow-up piston. The piston then moves upwards until it reaches a new equilibrium position. As the throttle port between the control valve core and the follow-up piston is accurately aligned, the zero loss flow rate and pressure drift of the CSV9 electro-hydraulic converter are very small, The load stiffness is high, and because it is a differential cylinder layout, the CSV9 electro-hydraulic converter also has hydraulic emergency function. In emergency situations, as long as the distance passes through the two position four way directional valve to reverse the P and T ports, or when pressure oil is simultaneously introduced at the P and T ports, the servo piston will immediately push down to low
Very specific, thank you for learning a lot of tools. I feel that I still need to be strengthened, and I appreciate that I still need to be strengthened for further education
When the pressure oil enters the electro-hydraulic converter from the P port and passes through the upper and lower adjustable throttling ports between the control valve core and the follow-up piston, and then returns through the T port, the oil pressure directly acts on the lower chamber of the follow-up piston, causing it to generate a constantly upward thrust. The control oil pressure between the upper and lower throttling ports acts on the upper chamber of the follow-up piston, causing it to generate a downward thrust. At this time, if there is no controlled current flowing through the dynamic ring, The control valve core is stationary because the flow area of the upper and lower throttling ports is preset to be equal, so the control oil pressure in the upper chamber is exactly half of the oil pressure in the lower chamber. Additionally, because the area of the upper chamber of the follow-up piston is preset to be twice the area of the lower chamber, the hydraulic thrust acting on both ends of the follow-up piston is equal, So the servo piston is stable in this balanced position without human labor. Please ask the skilled hands of the thermoelectric alliance to guide the layout and working principle of the SV9 electro-hydraulic converter. Thank you, I also want to understand the operation principle of the SV9 electro-hydraulic converter. It is simple and easy to understand. Who has the drawings? I am also looking for an electro-hydraulic converter. The working principle is that after computer calculation and processing, the electrical signal to open or close the steam valve is amplified by the servo amplifier, In the electro-hydraulic converter servo valve, the electrical signal is converted into a hydraulic signal, causing the main valve of the servo valve to move, and the hydraulic signal is amplified to control the passage of high-pressure oil. This allows the high-pressure oil to enter the lower chamber of the oil pump piston, move the oil pump piston upward, and use a lever to mobilize the steam valve to start working, or to release the pressure oil from the lower chamber of the piston, and use spring force to move the piston downward to close the steam valve. When the oil pump piston moves, At the same time, two linear displacement sensors (LVDT) are mobilized to convert the mechanical displacement of the oil pump piston into an electrical signal, which is used as a negative feedback signal and added to the signal sent by the front computer processing. Because the polarity of the two is opposite, in reality, they are subtracted. Only after the original input signal and feedback signal are added, and the signal input to the servo amplifier is zero, can the main valve of the servo valve return to the middle position, There will no longer be high-pressure oil flowing into the lower chamber of the oil pump or causing pressure oil to leak out from the lower chamber of the oil pump. At this time, the steam valve will stop moving and be connected to a new working position CSV9, CSV9H electro-hydraulic converter
The CSV9 electro-hydraulic converter consists of a dynamic coil force motor and a spool valve hydraulic servo driver, with its servo piston and control valve
The cores accept direct position feedback, thus being able to convert weaker electrical signal paths into displacement outputs with considerable thrust after being amplified by the process electro-hydraulic servo. The CSV9 electro-hydraulic conversion tool has advantages such as compact layout, sensitive response, high reliability, good dynamic characteristics, low requirements for oil cleanliness, and easy maintenance. Therefore, it is widely used in the electro-hydraulic governors of hydroelectric generator sets
Figure 2: I like the operation of steam turbines: Thank you for helping other members solve the questions they need to answer! Data flow+399KB Endless learning, come back and say thank you! Although the post has been around for some time and the questions that need to be answered have already been resolved, thank you to the forum's enthusiastic friends as usual! Reply 5 # rdxx
Stronger pollution capacity ≤ 1% plus CSV9H converter, except for electrical parameters that are different from CSV9, its adjacent size is completely the same as CSV9 converter, so it can
When the regulating current flows through the moving coil winding located in a fixed magnetic field with a magnetic gap, electromagnetic force occurs. This electromagnetic force overcomes the force of the spring and pushes the moving coil and the regulating valve core to produce a displacement proportional to the regulating current
