HELP!!

Now. Now. Now. If they did that us old farts would be unemployed ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

hi i am new in this forum.. but this is the best place to write my question i guess.. the problem is with the simulation of the circuit.. its a simple bridge rectifier circuit a simple adopter circuit actually which is supplied with 220V AC , 50Hz and out put with 9V DC and 300 mA ... well when i wanted to simulate it.. it gives error such these things

• C:\Documents and Settings\reaven\Desktop\Pspice\Schematic2.sch Reading and checking circuit Node $N_0002 is floating Node $N_0003 is floating Voltage source and/or inductor loop involving V_V1 Circuit has errors ... run aborted See output file for details Simulation aborted

thnx for your helps! good luck Yavuz Istanbul Tech

What is connected to node 2?

What is connected to node 3?

If you leave one side of a capacitor unconnected, the program has no way of deciding the initial capacitor voltage, since any charge could be trapped in the capacitor.

If you have only one side of many other components connected to defined voltages, some simulators complain that having an unconnected end produces a useless component that can carry no current.

Perfect inductors can circulate infinite current when connected to perfect DC voltage sources. Before a time simulation runs, the initial condition must be calculated, where all currents and voltages are assumed to be the values reached by the time they settle to steady state. An inductor across a voltage source settles to infinite current. If your circuit has a DC voltage source connected across an inductor, it probably is not what you intend to simulate.

What is voltage source V1 connected to?

This sounds a look like "simulating" an AM receiver with a diode on paper... almost all the introductory material you see shows the diode clipping the negative half of some nicely modulated AM signal and feeding it into a capacitor/load resistor detector to smooth out the variations, thus making it "obvious" how AM diode detection works.

...if only you could buy one of those ideal diodes in the first place!

What are you trying to simulate specifically ?

My mind boggles that ppl do this. Why not 'simulate' using a piece of paper ?

Graham

My mind also boggles that anyone would actually *want* to write at such length on this topic !

In any event such matters as DC R, winding inductance and coupling are entirely under the control of the transformer vendor ( unless *you* know how to specify ) and no amount of simulating will change that.

I defy anyone to better the pragmatic ' suck it and see ' version of ensuring it performs as required after doing the initial sums the good old-fashioned way and typically revisiting the transfomer design after the first iteration !!!

Graham

I have a simulator which gives the same waveforms as spice, but with additional information and you can input the data in seconds. It handles transformer voltage drop under load for you. You have to measure transformer primary and secondary windings with an ohmmeter, then measure no-load secondary voltage. This tool predicts real world performance closely.

If you go to

and download "Electro Tools" you will find the simulator as one of the simulator "worksheets".

Roger Lascelles

besides, simulating a rectifier-capacitor supply using a bit of paper is a lot trickier than you might think. Barton wrote an entire (albeit tedious) book on the subject....and I recently saw a paper in IEEE trans. power electronics on the topic.

Cheers Terry

specs are just words. what really counts is how the actual devices operate. This, of course, is why Deming, Juran et al go (went) on at great length about building long-term relationships with capable, trustworthy vendors.

why would a transformer design need multiple iterations?

If you are building say a 2.5MW multipulse rectifier, it might not be advisable to "suck it and see", especially wrt harmonics.

Cheers Terry