Magnetron with microprocessor power control

A microwave energy generating system comprising:

• a magnetron operable to generate microwave energy for cooking;
• a power transformer having a primary and a magnetron powering secondary;
• an inverter connected to supply power to said primary by selectively switching controlled switches;
• and
• a control circuit for controlling the operation of said inverter, said control circuit having an oscillator and operable to generate gating pulses to switch said controlled switches;
• and
• a microprocessor having a first output port operable to supply a power control signal of variable duty cycle to control circuit;
• and
• wherein the duty cycle of said power control signal controls the power of said magnetron, and wherein said control circuit includes a logic circuit connecting said oscillator to have controlled switches, said first output port being connected to supply the power control signal as a logic signal to said logic circuit, said logic circuit selectively providing said gating signals to said controlled switches as a function of the state of said power control signal.

A microwave energy generating system comprising:

• a magnetron operable to generate microwave energy for cooking;
• a power transformer having a primary and a magnetron powering secondary;
• an inverter connected to supply power to said primary by selectively switching controlled switches;
• and
• a control circuit for controlling the operation of said inverter, said control circuit having an oscillator and operable to generate gating pulses to switch said controlled switches;
• and
• a filament sensor for sensing a condition of a filament of said magnetron;
• and
• a microprocessor connected to receive a signal from said filament sensor and operable to monitor said condition of said filament, and wherein said power transformer further includes a filament powering secondary, and wherein said microprocessor causes said system to operate in a filament standby mode upon start up with the magnetron being off and said inverter operating to supply warm up power to said filament by way of said filament powering secondary.

A microwave energy generating system comprising:

• a magnetron operable to generate microwave energy for cooking;
• a power transformer having a primary and a magnetron powering secondary;
• an inverter connected to supply power to said primary by selectively switching controlled switches;
• a control circuit for controlling the operation of said inverter, said circuit having an oscillator and operable to generate gating pulses to switch said controlled switches;
• a magnetron sensor for generating a signal depending on the magnetron power;
• and
• a microprocessor connected to receive the signal from said magnetron sensor and operable to adjust the operation of the inverter for changing the magnetron power until the signal from said magnetron sensor is brought to a set point corresponding to a desired magnetron power, wherein said microprocessor is operable to change the magnetron power by changing the frequency of said inverter.

The microwave energy generating system comprising:

• a magnetron operable to generate microwave energy for cooking;
• a power transformer having a primary and a magnetron powering secondary;
• an inverter connected to supply power to said primary by selectively switching controlled switches;
• a control circuit for controlling the operation of said inverter, said control circuit having an oscillator and operable to generate gating pulses to switch said controlled switches;
• a magnetron sensor for generating a signal depending on the magnetron power;
• and
• a microprocessor connected to receive the signal from said magnetron sensor and capable to adjust the operation of the inverter for changing the magnetron power until the signal from said magnetron sensor is brought to a set point corresponding to a desired magnetron power, and wherein the microprocessor is operable to adjust the operation of the inverter for changing the magnetron power without changing the duty cycle of the gating pulses.