Can one connect a car alternator and a switched mode power supply in parallel on a network and run them at the same time without damage to either component?
My understanding given their implementation is as follows:
- car alternator is a 3-phase stator rectified by diode. Excitation voltage controlled by a voltage regulator circuit which stops excitation if voltage on the alternator output is higher than a threshold.
- looking into an SMPS, there are the smoothing transistors preceded by the rectifier diodes which rectify the transformer voltage. Voltage is controlled by PWM with the help of voltage sensing at output.
In consequence:
- It should be ok to connect both in parallel as both have internal diodes which avoid short circuits.
- If one sets the SMPS at a higher target voltage than the alternator one has a "priority" configuration in which the SMPS supplies (virtually all) the power to the network when it is switched on.
- When it is switched off, the alternator takes over power supply seamlessly.
- The smoothing capacitors in the SMPS will help to smooth the voltage in the network produced by the alternator (3-phase ripple) even if the SMPS is off.
Can anybody confirm this reasoning before I go and produce a cloud of smoke?