Performance characteristic (Figure 9)
n=f(T2) relationship between speed & torque.
I=f(T2) relationship between current & output power
η=f(T2) relationship between efficiency & torque 
P2=f(T2) relationship between output power & torque
(1)  I=f(T2)
I=TE/KT*Φ=(T0+T2)/KT*Φ=T0/KT*Φ+T2/KT*Φ=I0+[1/KT*Φ]*T2 (liner equation)
I0: no load current Φ: constant
At stall, n=0, E=0, according to Figure 6, current Ist=(U-2△U)/r
(2)  n=f(T2)
E=V-2△U-I*r=KEΦ*n
n=(V-2△U-I*r)/KE*Φ={U-2△U-[(I0+T2)/KT*Φ]*r}/KE*Φ
 =(U-2△U-I0*r)/KE*Φ-r/KE*KT*Φ2*T2
 = n0-[r/KE*KT*Φ2]*T2（equation of lines）
(3)  P2=f(T2)
P2=T2*n/9.55=[n0-(V/KE*KT*Φ2)*T2]/9.55=[n0*T2-(r/KE*KT*Φ2)*(T2)2]/9.55
P2 is a second-degree parabola (Figure 10)

(4)  η=f(T2)=P2/P1  η is a curve(Figure 11) 
(Equation iscomplicated thus is omitted here.)