Safety level of high voltage power source.
Well, let's take a closer look at the issue of safety
On picture is an internationally recognized graph of current danger through the human body
Zone AC-1 nad AC-2 (all under green line) is is a safe area without painful physiological effects
Zone AC-3 is safe areea with with unpleasant, but non-health-enhancing effects, you may get convulsions, but it will not kill you
Zone AC-4 (all over red curve c1 ) a dangerous current which can cause the fibroilation of the heart and the victim to kill
In other words
Current 30mA is in all time under red cuve.
Current 100mA is safe in time shorter than 500ms
Current 500mA is safe in time shorter than 10ms
Current 200mA is safe in time 100ms with reserve.
OK if have power supply with max output power 10W
everything fails, yet we are sure that max output current 200mA is possible max on voltage 50V, becouse P=U*I
50V is safe DC and AC voltage in all time and all environment (becouse human body have any resistence)!
I suspect that a 10W voltage source can not kill humans, under no circumstances, it prevents the resistance of the human body.
Let's take a look at real HW implementation of power supply.
For example when use as control IC MCU STM32F303.
Timer in MCU as PWM control MOSFET on primar 24V side timing for example 60% charging flyback transformem 20% dischrge and 20% as dead time.
Timer in MCU can be stoped by using internal hw comparators, this works on hardware level. If on internal comparator bring the voltage from the current measurement over the mosfet.
We have, in my view, a functional limitation of maximum power relized on hardware level.
Information about output voltage level is on MCU avalible over opticaly isolated amplifer. STM32F303 have two watchdog Windows and independen, I thing WWDG is good choice, becouse use same clocs as PWM times. If we set this timer on example 10ms we have hardware sure, MCU and PWM will be stoped when every 10ms, not refresh WWDG , ADC not measure output voltage and output voltage in time 10ms after start PWN not over 500V.
If all work we will measure every 10ms output voltage and if not over 500V (any error or big load on output make savety STOP. If sw not works make safety stop WWDG.
10W power supply on 500V can delivery max 20mA and 20mA is safety current level on every time and every voltage level.
In other safety level is possible relize anu over current protection on charging capacitor in primari side.
What do you think about it?