System and method for charging a capacitor using a constant frequency current waveform
US6417649B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 20, 2000 |
| Grant date | Jul 9, 2002 |
| Priority date | — |
| Expiry date | Sep 25, 2020 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/3904
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A system and method for charging a high-voltage capacitor through the application of current having magnitude that has a fixed frequency waveform. During a charging sequence in which the current is applied to the capacitor, the duty cycle of the fixed frequency current waveform is dynamically controlled based on the voltage state of the capacitor to modify the energy transfer according to the efficiency with which energy can be delivered to the capacitor. This optimizes the capacitor charging sequence, increasing the speed with which the high voltage capacitor is charged. Generally, energy is transferred from a power source to the capacitor via a magnetic element such as a fly-back transformer. A pulsed voltage supply provides voltage pulses having a constant frequency and an adjustable duty cycle to a primary winding of the transformer. Initially, there is no energy stored in the transformer core. As a result, the duty cycle of the initial voltage pulse is of sufficient duration to accumulate stored energy in the transformer core. Once a predetermined quantity of energy is stored in the transformer, the transformer is controlled to generate a current to charge the capacitor. The m…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.