High frequency cathode heater supply for a microwave source
US8976542B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 11, 2010 |
| Grant date | Mar 10, 2015 |
| Priority date | — |
| Expiry date | May 17, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J25/587
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A high frequency cathode heater supply for a microwave source includes a SMPS inverter and an isolation transformer having a primary winding arranged to be powered by the SMPS inverter, a monitor winding passing through primary core assemblies of the primary winding and a secondary winding arranged for connection to the cathode heater. A current monitor is arranged to monitor a current in the primary windings. Signal processing modules are arranged to receive a first input signal from the monitor winding indicative of a voltage across the cathode heater and a second input signal from the current monitor indicative of a current through the cathode heater. The signal processing modules are arranged to output a control signal to the SMPS inverter to control power supplied to the cathode heater dependent on a monitored resistance of, or monitored power supplied to, the cathode heater as determined from the first input signal and the second input signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.