A permanent magnet direct current machine is used as a generator, driven by a mechanical assembly...

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A permanent magnet direct current machine is used as a generator, driven by a mechanical assembly at the speed NOTnot--3000 rpm. The rated voltage of the generator is Unot--220 V, rated power Phot--20 kW and nominal efficiency:- 0.8 1) Represent an equivalent diagram of the generator and its load (use an appropriate convention). 2) Calculate the nominal current value of the generator. 3) Deduce the value of the armature resistance if the mechanical losses of the machine are neglected. 4) Then calculate the value of the no-load voltage and the half-load voltage, i.e. for a power supplied P-not- P 2 5) Calculate the efficiency of the machine at half load. A permanent magnet direct current machine is used as a generator, driven by a mechanical assembly at the speed NOTnot--3000 rpm. The rated voltage of the generator is Unot--220 V, rated power Phot--20 kW and nominal efficiency:- 0.8 1) Represent an equivalent diagram of the generator and its load (use an appropriate convention). 2) Calculate the nominal current value of the generator. 3) Deduce the value of the armature resistance if the mechanical losses of the machine are neglected. 4) Then calculate the value of the no-load voltage and the half-load voltage, i.e. for a power supplied P-not- P 2 5) Calculate the efficiency of the machine at half load.