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Motor output torque:

The torque that makes a mechanical element rotate is called rotational torque, or torque for short. Mechanical components under the action of torque will produce a certain degree of torsional deformation, so the torque is sometimes also called torque.

Torque as a function of power and speed:

Torque (T) = 9550 * power (P) / speed (n)   

That is:T=9550P/n-formula [1

From this, it can be deduced that

Torque=9550*Power/RPM 

Power = rotational speed * torque / 9550, i.e:

P=Tn/9550 - formula [2

In the equation:

P-unit of power (kW);

n-unit of rotational speed (r/min);

T-unit of torque (N.m);

9550 is the calculation factor.

Power kw Rotational speed rpm Torque Nm

0.05 3000 0.16 

0.4 3000 1.27 

0.75 3000 2.39 

1 3000 3.18 

1.2 3000 3.82 

1.5 3000 4.78 

How is the motor torque calculation formula T=9550P/n calculated?

Analysis: Power = Force * Speed 

That is: P = F * V ------- formula [3

Torque (T) = torque (F) * radius of action (R)

Introduced: F = T / R ----- formula [4

Linear velocity (V) = 2πR * revolutions per second (rev/sec) = 2πR * revolutions per minute (n/min)/60 = (πRn/30)/min ----- formula [5]

Substituting equations [4] and [5] into equation [3] gives

P=F*V=(T/R)*(πRn/30)=Tπn/30 

P=Power unit W.     

T=Torque unit N.m.

n = revolutions per minute in revolutions per minute;

If the unit of P is replaced by KW.

then it is the following formula:

P*1000=Tπn/30;

P*1000*30/π=Tn;

(30,000/3.1415926)*P=T*n;

9549.297*P=T*n.

This is why there is a 9550 coefficient relationship between power and torque*speed.

The relationship between motor torque, speed, voltage and current:

Since the electric power P = voltage U * current I, that is, P = UI ---- formula [6

Since the unit of power P in formula [2] is kw, while the unit of voltage U is V, the unit of current I is A, and the unit of UI product is V.A, that is, w, so the formula [6] will be substituted into formula [2], UI needs to be divided by 1000 to unify the units.

Then:

P = Tn/9550 = UI/1000 ---- formula [7

== " Tn/9.55 = UI ---- formula [8

== " T=9.55UI/n---- formula [9]

== "U=Tn/9.55I---- formula [10]

== "I=9.55U/Tn---- equation [11

In equations [7], [8], [9], [10], [11]:

P-unit of power (kW);

n-unit of rotational speed (r/min);

T-unit of torque (N.m);

U-unit of voltage (V);

I-unit of current (A);

9.55 is the value after 9500 ÷ 1000.