A control apparatus for an internal combustion engine can control an
actual operating characteristic with high precision by shortening a
response time thereof. The control apparatus capable of changing an
actual phase angle of a camshaft by an OCV includes a crank angle sensor
for detecting a crank angle of a crankshaft and generating a crank angle
signal, an actual phase angle detection section for detecting the actual
phase angle of the camshaft, an air flow sensor and a throttle position
sensor for detecting an operating state of the engine, a target phase
angle calculation section for calculating a target phase angle based on
the operating state, and a phase angle feedback control section for
calculating an operation amount to the OCV so as to make the actual phase
angle coincide with the target phase angle. The phase angle feedback
control section calculates the operation amount in synchronization with
the crank angle signal.