Hello
I want to make a bldc esc using ir2101.

In the picture below, the Vgs of the high side mosfet exceeds 20V, and I wonder how to solve this.

 

According to your schematic VGS can be up to 20V. If you are only making a few of these, don't worry. If you are going to manufacture these for sale, put a suitable zener diode such as a 1N5246B from the gate to source to clip the VGS to about 16 volts. Check to assure that R_gate's power dissipation does not exceed more than about 70% of
R_gate's rated power

 

The reason the voltage rises so high is because the motor acts like a transformer. So consider changing the common connection of the controller ICs. OR, connect the common in the motor to the common in the control circuits.

 

In the picture below, the Vgs of the high side mosfet exceeds 20V, and I wonder how to solve this.

Fix this in three places.