Image forming apparatus and image forming method

An image forming apparatus that uses a switching element to switch current flowing to an excitation coil, so that the excitation coil generates magnetic flux that causes an electromagnetic induction heating layer in a fixing member to produce heat, the heat fixing an unfixed image formed on a transported sheet to the transported sheet, the image forming apparatus comprising:

• a detection unit configured to detect a temperature of the fixing member;
• a calculation unit configured to calculate a change in temperature of the switching element over time;
• a prediction unit configured to determine, at a first time point, a predicted temperature of the switching element at a second time point in accordance with the change in temperature of the switching element up until the first time point, the first time point being a predetermined time before the second time point, and the second time point being a time at which a tip of the sheet in a direction of transportation is scheduled to arrive at the fixing member;
• and
• a control unit configured to perform first control, from the first time point until the second time point, when the predicted temperature of the switching element is at least a predetermined value, the first control controlling power supplied to the excitation coil by restricting switching of the switching element and lifting the restriction, so that by the second time point the detected temperature of the fixing member reaches a temperature necessary for fixing.