Proposed high-voltage power supply (EBP) is used to generate the high voltage supply elektroefflyuvialnaya chandelier (Chizhevsky) - generator of negative ions.
For household chandeliers recommended voltage is 30...35 kV. The proposed EBP fully meets the high requirements of operational safety.
EBP consists of a mains voltage rectifier diode bridge VD1, filter capacitor C1 and the high-voltage half-bridge oscillator on the chip DA1 (KGS). DA1 chip converts the rectified mains voltage in high frequency (30...50 kHz). Transformer T1 serves to provide the necessary voltage on the control windings L1, L3 and for galvanic isolation of the high voltage winding from the mains.
(click to enlarge)
EBP works as follows. The rectified mains voltage is supplied to the IC DA1, starting a chain R2-C2 starts the oscillator IC. Chain R3-C3 and R4-C4, set the frequency of the oscillator. When R3 and R4 stabilize the length of the respective half-cycles of the frequency of the generated impulses.
The output voltage is increased hundreds of times in the output winding L4 of the transformer and is fed to a rectifier of the circuit of the voltage multiplier for high voltage capacitors C7...C12 and diodes VD2...VD7. Rectified voltage of negative polarity is supplied to the chandelier through a current limiting resistor R5.
Details and design
Capacitor filter network C1 must be rated for a working voltage of 450 V (for example K50-29), C2 may be of any type, for a voltage of 30 V. the Capacitors C5, C6 chosen in the range of 0.022 to...to 0.22 UF operating voltage not less than 250 V, for example type K71-7, K73-17. Capacitors C7 multiplier...C12 - type SWИ-3 at a voltage of 10 kV. Can be replaced by any of a number K15-4, K73-4, CEM and others at a working voltage of at least 10 kV.
High voltage diodes VD2...VD7 - type CCG (possible replacement for CCD). A current limiting resistor R5 - type KEV-1. You can replace the three resistors MLT-2 to 10 MW each. As a transformer, you can use any flyback transformer from black and white TV. High-voltage winding is left, the rest are removed, and in their place put new windings.
The windings L1, L3 contain 7 turns of wire PEL 0 to 0.2 mm. and a coil L2 - 90 turns of the same wire.
Special attention should be paid to the installation of capacitors and diodes of the multiplier. The connecting wires between them should be as short and brazing conclusions - even and smooth. High-voltage wire must be passed through the insulating rubber grommet in the housing EBP.
As a high-voltage wire connecting the EBP with the chandelier, you can use a TV antenna cable brand RK with a diameter of 8 mm, after removing the outer insulation and shielding braid.
Establishing
On control windings L1 and L3 must be voltage 4...5 V. If there is no output voltage, it is necessary to swap the conclusions of the windings L1 and L3. Next you need to ensure the absence of corona, for which EBP is included in the dark. If the power pins appear purple lights - a sign of corona. Usually, the effect of corona is accompanied by the smell of ozone. Off out areas of corona varnish UR-231 or pour melted paraffin.
Author: V. Shinkarenko, Fryazino, Moscow region; Publication: N. Bolshakov, rf.atnn.ru