In many diesel engines, a temperature-controlled glow plug is used. This kind of glow plug is equipped with a heating coil, which actually consists of three coils, a retardation coil, an equalizing coil and a sudden heating coil, and the three coils are connected in series.
When the current passes through the glow plug, the temperature of the surge coil at the tip of the glow plug rises first, making the glow plug glow hot. Since the resistance of the equalizing coil and the retarding coil increases sharply with the temperature of the sudden heating coil, the current passing through the sudden heating coil decreases. The glow plug controls its own temperature in this way. Some glow plugs are not equipped with equalizing coils due to their temperature rise characteristics. The temperature-controlled glow plug used in the new super glow plug does not require a current sensor, which makes the preheating system more simplified.
