Unless the mains cable colours are completely different from what is used in the UK, the capacitor isn't connected to ground. If the capacitor did connect to ground, the fan would trip an earth leakage circuit breaker.
Green/yellow is normally ground. Green/yellow in the mains supply cable connects to green/yellow in the motor cable, which probably earths the motor case. It doesn't carry any current in normal use.
Brown is normally live. That connects to the black wire on the motor and to one side of the capacitor, a white wire. The other side of the capacitor, also a white wire connects to the brown wire on the motor. The blue wire, which is normally neutral connects to the motor.
Anyhow, that is how I understand your photo. The motor is a capacitor run induction motor.