Internal combustion engine controller

An internal combustion engine controller, comprising:

• a voltage boost circuit for supplying a switching current from a battery power supply voltage to a voltage boost coil and storing, into a voltage boost capacitor through a charging diode, a high voltage generated in the boost coil when a level of the switching current is reduced;
• a regenerating circuit for controlling an injector current using the high voltage stored within the boost capacitor and regenerating electrical energy of an injector to said voltage boost circuit when a level of the injector current is reduced;
• and
• a discharge switching element for being provided in parallel to the charging diode;
• wherein:
• if the high voltage stored within the boost circuit exceeds a required overboost compensation starting voltage,
• when the voltage boost switching operation is in progress, said regenerating circuit controls that electrical energizing of said discharge switching element is suppressed, and
• after the voltage boost switching operation, prior to electrical energizing of said discharge switching element, a dead time that allows for a delay time required for said boost switching element to cut off a current is provided and said regenerating circuit controls that said discharge switching element is energized to discharge the current from the boost capacitor to the battery power supply, and
• if the high voltage stored within said voltage boost circuit decreases below a required boost starting voltage,
• after the electrical energizing of said discharge switching element, prior to a shift to boost operation by electrical energizing of said boost switching element, a dead time that allows for a delay time required for said discharge switching element to cut off a current is provided and said regenerating circuit controls that said boost switching element is energized.

An internal combustion engine controller, comprising:

• a voltage boost circuit for supplying a switching current from a battery power supply voltage to a voltage boost coil and storing, into a voltage boost capacitor through a charging diode, a high voltage generated in the boost coil when a level of the switching current is reduced;
• a regenerating circuit for controlling an injector current using the high voltage stored within the boost capacitor and regenerating electrical energy of an injector to said voltage boost circuit when a level of the injector current is reduced;
• and
• a discharge switching element for being provided in parallel to the charging diode;
• wherein, if the high voltage stored within said voltage boost circuit exceeds a required overboost compensation starting voltage, said regenerating circuit controls that said discharge switching element is electrically energized to discharge the high voltage into the battery power supply through the boost coil.