Causes of broadcast storm:

Incorrect network design and plan
Network equipment damage
HUB is easily lead to broadcast storm as broadcast equipment
NIC or switching equipment damage
Network loop
Incorrect router configuration
Virus

How to detect Broadcast Storm:
step1. Set up broadcast packets filter
Open Filter –> Add –> From Filter Table, check "Broadcast":

step2. Detect relevant parameters of the broadcast storm

1. Statistical parameters

broadcast [...]