Solenoid valves are the "switching muscles" of automated fluid control, widely used in large quantities. However, the focus of industry competition is shifting: low power consumption addresses "where does the electricity come from", intelligence addresses "state awareness", and corrosion resistance addresses "living longer". This article breaks down three major directions: "driving force → technical route → selection impact".

Example: A valve body controller electromagnet lacks a positioner function.
The valve body relies on the coil being energized to attract the armature, which in turn pushes the valve core away from its initial position and into its working position. When the coil is de-energized, the valve core returns to its initial position due to the action of the return spring. To maintain the valve core in its working position, the coil must be continuously energized. Therefore, conventional electromagnets have high energy consumption.

The working principle of an electromagnet can be summarized as a chain: current passing through a coil generates a magnetic field (current magnetic effect) → the coil concentrates the magnetic field into a tubular shape → the soft iron core is magnetized, amplifying the magnetic field hundreds or thousands of times → the magnetic circuit and air gap determine the actual output suction force. After power is cut off, the magnetic domains of the iron core return to disorder, and the magnetism disappears - this is the physical essence of the "controllability" of an electromagnet.