please tell me in the following link (https://www.onsemi.com/pub/Collateral/ESD9101-D.PDF), the ESD diode with zener configuration is equivalent to a circuit containing diode, transistor and zener diode, so how this could be equivalent and how this equivalent circuit works
The data sheet front page tells that it uses "SCR technology" and that is what the equivalent circuit on the front page shows you: -
To understand how the circuit works you need to study how an SCR works and, once you have done that, it should become fairly clear: -
Initially, when an over-voltage occurs, the zener diode (on the right in the equivalent circuit) causes the PNP transistor to conduct and when enough current is flowing through the resistor, the NPN turns on and that action, in turn causes the PNP to turn on even more hence, you get a clamp that becomes a latch.
It is neither equivalent to a power zener diode nor equivalent to a standard TVS diode because of that SCR action.