Inverter:- classification of inverter and Auxiliary commutation inverter ( The MC murray inverter) with mode of operation

 INTRODUCTION OF INVERTER:- 

Inverter is an electronic device by this device we can change DC current to AC current means they can change Direct current into Alternating current at a desire output frequency and voltage with the help of Inverter.

DC current means the current of battery and AC current means the current which comes from transformer. 

Classification of inverter :-
Classification according to wave shapes of output :-

Square wave inverter :- 

A square wave inverter produces a square wave AC voltage at constant voltage of this type of inverter can be controlled by the DC input voltage.

This type of inverter give me a square wave AC voltage.

Pulse width modulation:- 

It uses as a switching scheme inverter to modify the shape of the input waveform to give a desired output waveform.

Classification of inverter according to commutation :-

Line Commutation inverter :- line committee Sun inverter based on the natural commutation.

forced commutation inverter :- forced commutation inverter are based on the principle of forced commutation inverter process.

Classification of inverter according to connection :-

Series inverter
Parallel inverter
Bridge inverter

Types of forced commutation inverter:-

• Auxiliary commutation inverter ( The MC murray inverter)
• Complementary commutated inverter (Mc Murray bed ford half bridge inverter)

Auxiliary commutation inverter ( The MC murray inverter)

Introduction of Auxiliary commutation inverter

The Mc murrays inverter is a impulse commutative inverter which is basedon LC circuit and auxiliary thyristor for commutation in load circuit.

Circuit diagram of mc murray inverter 

This impulse is derived from the regulating LC circuit which is applied to turn OFF a thyristor which carrying a load current.
This circuit consist of main thyristor T1 ,T2 , T3 & T4 ,and Diode D1, D2,D3 & D4 and Auxiliary thyristor TA1, TA2, TA3 & TA4 and L & C component.
When theThyristor pair T1 and T2 conducts load is connected to DC current source causing a positive voltage across the Load .
When thyristor pair T3 and T4 conducts a negative voltage is produces across the load.

The mode of operation of this inverter is divided into various operating mode which is given below :- 

MODE 1 :- In this mode the thyristor pair T1 and T2 is triggered Then thyristor T1 and T2 becomes turn on the supply current which flow through the path. 

Edc (+)→T1 → EL( Load , ZL ) →T2→ Edc (-) 

hence +ve load voltage EL is obtained.

Mode 2 :- By this mode when thyristor TA 1 and TA2 are trigger to turn OFF the main thyristor T1/ T2 which are conducting when thyristor TA1/TA2 have been turned ON capacitor C1 and C2 start discharging by path
Capacitor C2 discharging path
C1 (+) →T1 →TA1 → L → C1(-)
Capacitor C1 dischargeing path
C2(+) →L →TA1 → T2 → C2(-)

Mode 3 :- when resonanting excessive current IL ,the excessive current Ic - IL = ID1 or ID2 calculated through feedback diode D1 or D2. The path for D1 is

 C1(+) →D1→TA1→L→C1(-) 

and path for D2 is

 C2(+)→ L→ TA2→ D2 →C2(-)

Mode 4:- This mode start working when diode D1 and D2 stop conducting and the capacitor recharge the load at the constant current lL.

Mode5:- This mode start working when the capacitor voltage tends to the greater than Edc and diode D3 and diode D4 becomes in forward biased. The energy stored in the inductor L is transferred to the capacitor, causing it to be overcharged with respect to supply voltage Edc.