Abstract: A high-frequency power supply system includes an anomaly detector 3 which detects an anomaly occurring in a circuit on the side of a load L as from an outputting end A of a high-frequency power source 1. The anomaly detector 3 includes a first detector 21 which detects a voltage value Vf of a high-frequency forward wave, a second detector 22 which detects a voltage value Vr of a high-frequency reflected wave, a reflection coefficient calculator 23 and a differentiator 24 which calculate a reflection coefficient differential value d?/dt from the forward wave voltage value Vf and the reflected wave voltage value Vr, and an anomaly determiner 25 which determines of an occurrence of an anomaly based on the reflection coefficient differential value d?/dt. When the anomaly detector 3 outputs an anomaly detection signal to the high-frequency power source 1, high-frequency power source 1 stops its power output operation.

Abstract: A high-frequency power supply system includes an anomaly detector 3 which detects an anomaly occurring in a circuit on the side of a load L as from an outputting end A of a high-frequency power source 1. The anomaly detector 3 includes a first detector 21 which detects a voltage value Vf of a high-frequency forward wave, a second detector 22 which detects a voltage value Vr of a high-frequency reflected wave, a reflection coefficient calculator 23 and a differentiator 24 which calculate a reflection coefficient differential value d?/dt from the forward wave voltage value Vf and the reflected wave voltage value Vr, and an anomaly determiner 25 which determines of an occurrence of an anomaly based on the reflection coefficient differential value d?/dt. When the anomaly detector 3 outputs an anomaly detection signal to the high-frequency power source 1, high-frequency power source 1 stops its power output operation.

Abstract: A high-frequency power supply system includes an anomaly detector 3 which detects an anomaly occurring in a circuit on the side of a load L as from an outputting end A of a high-frequency power source 1. The anomaly detector 3 includes a first detector 21 which detects a voltage value Vf of a high-frequency forward wave, a second detector 22 which detects a voltage value Vr of a high-frequency reflected wave, a reflection coefficient calculator 23 and a differentiator 24 which calculate a reflection coefficient differential value d?/dt from the forward wave voltage value Vf and the reflected wave voltage value Vr, and an anomaly determiner 25 which determines of an occurrence of an anomaly based on the reflection coefficient differential value d?/dt. When the anomaly detector 3 outputs an anomaly detection signal to the high-frequency power source 1, high-frequency power source 1 stops its power output operation.

Abstract: A high-frequency power supply system includes an anomaly detector 3 which detects an anomaly occurring in a circuit on the side of a load L as from an outputting end A of a high-frequency power source 1. The anomaly detector 3 includes a first detector 21 which detects a voltage value Vf of a high-frequency forward wave, a second detector 22 which detects a voltage value Vr of a high-frequency reflected wave, a reflection coefficient calculator 23 and a differentiator 24 which calculate a reflection coefficient differential value d?/dt from the forward wave voltage value Vf and the reflected wave voltage value Vr, and an anomaly determiner 25 which determines of an occurrence of an anomaly based on the reflection coefficient differential value d?/dt. When the anomaly detector 3 outputs an anomaly detection signal to the high-frequency power source 1, high-frequency power source 1 stops its power output operation.

Abstract: The microwave generator with use of a magnetron comprises a microwave detector for detecting microwave output from the magnetron and a filament life diagnostic circuit for judging the life of filament of the magnetron by decreasing an input power to a filament of the magnetron from a normal state of the magnetron while monitoring the microwave output from the magnetron by the microwave detector, comparing the input power in the normal state of the magnetron with that just before the magnetron becomes unstable and judging the filament life based on the difference between the input power of the normal state and that just before the unstable state.

Abstract: In a microwave generator apparatus including a magnetron having a filament and an anode and generating a microwave, a filament power source supplies a filament power to the filament of the magnetron, and an anode power source applies an anode voltage between the filament and the anode of the magnetron. Then a parasitic oscillation detecting circuit detects a parasitic oscillation voltage superimposed on the microwave generated by the magnetron, and a filament power controller, in response to the parasitic oscillation voltage detected by the parasitic oscillation detecting circuit, controls the filament power source to control the filament power so that the parasitic oscillation voltage is made smaller.