H bridge circuit simulation in LTSpice

[electronicsLearner77]

I am referring to the video SVPWM and at 6.06


I tried to simulate the same circuit in LTspice, two issues i am facing
a. I am not able to create a neutral point by connecting two DC power supplies, is neutral here same as ground?
b. The voltage across AB is not VDC or 15V which is expected.
Please help what mistake i am doing.

 

[Alec_t]

Please post you .asc file.

 

[electronicsLearner77]

Please find the asc file.

 

[Alec_t]

a. I am not able to create a neutral point by connecting two DC power supplies, is neutral here same as ground?

LTspice doesn't know what 'neutral' means. With the two DC supplies in series, the node where they connect can be used as circuit ground if you wish. In that case connect the ground symbol there.

b. The voltage across AB is not VDC or 15V which is expected.

The high-side FET (M1 or M4) needs its gate voltage at least 4V higher than its source voltage to turn on sufficiently (as per the datasheet). High-side FETs are often driven using a capacitor 'bootstrap' circuit, which boosts the gate voltage above the drain voltage.

 

[crutschow]

is neutral here same as ground

The word "neutral" is normally only used to designate the non-hot terminal in electrical wiring.
LTspice requires at least one ground connection, which can be any arbitrary point in the circuit, to which all voltages are referenced.