It could be a problem with the piezo ignition system - the bit that generates a spark for ignition. On our Cannon cooker you have to push a button to ignite the hob but the oven is automatic; when you turn it on it automatically generates a spark until the gas lights. I guess that if the gas doesn't light within a short time the gas to the oven is automatically turned off. If your ignition system has failed, which could be the reason for the electricity tripping out, the oven won't work.
You could always try lighting the oven with a flame as an emergency measure; it may or may not work.