Solenoid controled by Arduino and Ramps 1.4

Hi,
i am using Arduino MEGA and RAMPS 1.4 to control device like 3D printer (deposition of metal powder).
I need to control solenoid (12V 20N JF-0826B ). Solenoid open and close nozzle. But nozzle stays open for like 5 min, so solenoid is overheating. I need high power when solenoid opens or closes nozzle but then i need only half or less of that power.
I also need easy contolling (like setPinState). I tried to use MOSFET IRF520, and PWM to Voltage Converter Module. With some PWM pin i control PWM to V conventer and with voltage from that conventer i control MOSFET. But when i set for example V 2.25 to gate of MOSFET output voltage and current of MOSFET slowly rises. So solenoid is overheating and in reality i dont control it.
Can someone advce me how to control solenoid to have 3 states (full power, half power(or something like that), OFF)?

... there is something like "chopper-driving", where you have a capacitor as "power-bank" for the switching current, which is loaded with a small current, which won't overheat the driver, if switched.

So while OFF, the capacitor is loaded to full capacity, which gives enough current to activate the solenoid when the driver is switched ON ... then only the limited current is drawn, which is strong enough to "hold" the solenoid, but not enough to overheat ...

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Viktor
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thanks, that help