Theory of Operation
High Frequency Power Converter
The Truecharge 10 uses modern high frequency switching power circuits to convert the alternating current from the utility line to the low voltage direct current required to charge the battery. The circuits are similar to those used in power supplies for computers and other modern electronic equipment.
The alternating current from the utility line is first rectified by diodes to produce a high voltage direct current.
This direct current is switched at a very high frequency (approximately 75 kHz) to produce pulses of current which are stepped down to a lower voltage by a small high frequency transformer. The low voltage pulses of current from the secondary side of the transformer are rectified and smoothed to create a continuous direct current which is sent to the battery.
The power switching is performed by power MOSFET transistors. These transistors also control the charging current and voltage through a process called pulse width modulation (PWM). The average value of the voltage or current is controlled by varying the lengths of the pulses of current. Shorter duration pulses result in lower voltage and current while longer duration pulses result in higher voltage or current.
The advanced power conversion technology in the Truecharge 10 gives you several benefits:
•A charger that is smaller and lighter than most other chargers with similar capabilities. The Truecharge 10 is easy to carry with you and can be stored or installed in small compartments.
•A totally silent charger. There is none of the “hum” or “buzz” commonly associated with chargers based on older technology.
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