LLC Resonant Converter for HiFi use?

[dch53]

The LLC Resonant converters I bought are indeed just mains rectification and filtering followed by the LLC Resonant Converter. No PFC.

Something I will try over the next few days with one of these units is putting a high voltage linear regulator (https://neurochrome.com/products/21st-century-maida-regulator) between the mains rectification and filtering and the converter.

Thanks for tip about common mode noise and scope readings. I'll do some measurements with small spring tip instead of the long ground lead. I've seen 2.54 millimeter female breakaway headers soldered to PCBs for attaching these tips. My process for testing high voltage equipment is to put all metre and scope probes in place with the equipment off, turn on and stand back. Take readings and turn off.

I don't have an isolation transformer.

I'll put some requirements together for a new power supply and we can take it from there. The one I have has 5 DC output voltages 420V, 8V, 8V, 6.3V and -150V. That increases the complexity of the transformer. Only the 420V has a control loop. The 2 8V supplies and the 6.3V supplies have buck converters. The -150V supply is a simple single transistor regulator.

[jonpaul]

Hello again: you cannot work on mains powered SMPS/LLC/Res to design or debug withotu a 240/240V isolation transformer.

One can buoild it from 2 LV transformers bvaxk to back of similar VA rating


eg

240V>>>T1 24V =====24V>>T2 >>240V isolated

Jon

[dch53]

Thanks Jon.

[jonpaul]

DCH53 Addig PFC as Farrington suggest will add EMI but regulate the 360VDC bus into the LLC.

Suggest some background learning and reading (NOT you tube):

1/ Power Supply Mesurent app note/book from HP in 1980s

2/ Tektronix Circuits Concepts books:
Oscilloscope Probe Circuits
Oscilloscope Probe measurements.

PDF easily  to find.

j