Phase-Phase Compensation

I made compensators for two phase welding machines sucesfully. Only need one capacitor connected between phases. Capacitor must be calculated using phase angle of non compensated machine and later corrected in fuction of on time - off time. Power bills reduces dramatically. If you need more details don't forget to email me at eduardoreimundo@arnet.com.ar

Thank for your answer on CR4 webpage. Our problem is different here. In Turkey electrical counters work totaly different. Let me try to explain Lets say that in the sum of three phase we have 300KVAr inductive and 200KVAr capasitive. usually the resultant vectorial sum is 100KVAr inductive. but in turkey it is different. The calculations are made for each phase separately. so you have to think of each phase alone. so we can not think of it like system usually but like phase phase. and we pay also for capasitif as well as inductive. for example R is 200KVAr Inductive, S is 100KVAr capacitive and T is 100KVAr Capasitive in all the worl the total is 0 in turkey it is 200KVAr Capasitive and 200KVAr Inductive!!! for this reason we need trigger circuit to take the Capacitor when the device is on and takes is out when the device is off. in such case thyristor are the best option with microcontroller. I have some sample circuits but I still need more details Please inform me if you know any detail about this issue.

I am not an engineer, but I am a welder. have you tried Miller Electric? (Millerwelds.com) they have welders that have "autolink" and they hook up to any power supply and automatically adjust to that power source. even if they don't have it , you could tell them your story and they might try to fix it! maybe as a story in their newsletter.(they solve weling needs in it)

What is your power factor

go to www.elspec-ltd.com they have manufactured the exact equipment that you are trying to design, the secret is to be able to achieve full compensation in 20milliseconds or less, for welding applications the var compensation cannot be stepped in over long periods of time. We have supplied over 5mvar of "unbalanced" real-time reactive compensation to a local vehicle manufacturer for the welding lines. The unbalanced approach means that the system is made up of individual phase to phase steps which independantly apply correction across the 3 legs of the delta. the control algorithm is extremely complex as to enable the system to work effectively the capacitors need to be available for switching at all times and cannot wait for a discharge time before reconnecting to the network. Please contact me should you require further info.