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glene77is:
Yes. One transformer secondary is in series with one motor coil. Or if you want the motor coil is in parallel with the secondary. In this case it will be a function of what you want to study and the accuracy of the result.
Consider a simple case: A battery, switch, resistor, and a capacitor all in a series connection. Sometimes this battery will be assumed ideal, usually the case for circuit analysis. Idea means constant voltage independent of load current, and zero internal impedance.
The resistor and capacitor are assumed idea. The resistor is only a resistor and the capacitor is only a capacitor. In real life this is not the case, but may be very close for some components at some frequencies.
Now, let's suppose that all the resistance is the internal resistance inside the battery, and there is no switch. Connect the capacitor to the battery. Relative to the battery terminals we can describe this as a parallel circuit. Seems reasonable.
However, if I want to determine the voltage on the capacitor as a function of time following the connection of the capacitor to the battery, then I would analyze the circuit as a series RC circuit being driven by a voltage source. The analysis will consist of writing an equation like Vbat - iR - q/C = 0. This is the sum of the series voltage drops. This also can be written as R*dq/dt + q/C - Vbat = 0 . For a solution see some books on differential equations. However, by inspection, you can see that the initial current at the time of switch closure with 0 charge on the capacitor is Iinitial = Vbat/R . If the initial charge on the capacitor was such that the capacitor voltage was Vbat/4, then the initial current would be Iinitial = (Vbat - Vbat/4) / R .
Basically you draw an equivalent circuit for what you want to analyze. This is a model of the real world circuit where you include the important components and exclude those you consider unimportant. Then you analyze the equivalent circuit.
For example: A 1000 ft length of coaxial cable may have a capacitance of 50,000 pfd as measured at a low frequency. This capacitance is not concentrated at one small point. Rather it is uniformly distributed evenly over the entire length. At 60 Hz I might assume this is one small capacitor 1" long for my equivalent circuit. However, at 144 mHz I can not do that because the wavelength of this frequency is 2 meters. Now I need to treat this device (coax cable) as a transmission line. If I apply a DC voltage to one end of this cable and a light bulb as a load at the other end, then for steady state purposes I do not care about the capacitance, or transmission line characteristics, but only the total loop resistance.
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