| 摘要 |
In order to operate a low voltage source from a mains voltage power supply, such as an electricity meter, the alternating current (AC) mains voltage must first be converted to direct current (DC). It is common practice in low cost power supplies to make use of a very simple arrangement of components to reduce the high ac voltage to a lower useable dc voltage, such systems operating in a half wave rectification mode to reduce the circuit component numbers. This makes for inefficient DC voltage supplies. The present invention seeks to address a need to increase an amount of available electrical energy to operate the low voltage circuit requirements of an electricity meter without increasing the energy taken from the mains voltage. The present invention provides a power supply of which both cycles of an input alternating current are employed through the use of an inductor based circuit. During the negative half-cycle, current from Diode D32 flows through inductor L31 which stores the energy, which is released by diode D33 during the positive half-cycle. A switch (Q1, see figure 4) may be used to pulse or chop the current so that a smaller, less costly inductor L31 may be used. |
