powerelec
Junior Member level 2
Hi, I have a couple of questions about flyback converters. Your help in answering these is much appreciated!
1) I have read some papers in which isolated flyback operating from the AC mains, sometimes use constant on time DCM control to get high power factor. I understand why this is so. But if the output load is constant then we end up needing a very high value output capacitor and a very slow feedback loop to filter out the 60 Hz ripple. Is there any technique to keep power factor high and also deliver constant power to the load?
2) I have a problem understanding the electricity-to-magnetism-to-electicity conversion when there are two windings on the secondary side of the flyback. When the switch is off, both the windings on the secondary side have a voltage of V. So why the primary side MOSFET drain does not go to VIN+V+V. Instead it goes to VIN+V. Could you please explain this.
Thanks!
1) I have read some papers in which isolated flyback operating from the AC mains, sometimes use constant on time DCM control to get high power factor. I understand why this is so. But if the output load is constant then we end up needing a very high value output capacitor and a very slow feedback loop to filter out the 60 Hz ripple. Is there any technique to keep power factor high and also deliver constant power to the load?
2) I have a problem understanding the electricity-to-magnetism-to-electicity conversion when there are two windings on the secondary side of the flyback. When the switch is off, both the windings on the secondary side have a voltage of V. So why the primary side MOSFET drain does not go to VIN+V+V. Instead it goes to VIN+V. Could you please explain this.
Thanks!