Power Supply Apparatus for Traveling-Wave Tube Helix Electrode Protection
Solution Overview
Problem
Existing power supply apparatuses for traveling-wave tubes face issues with high current flow through the helix electrode due to potential differences between the anode and cathode electrodes, leading to characteristic deterioration and increased power consumption, especially when using high-voltage transistors and expensive vacuum relays to control the anode voltage.
Innovation Solution
A power supply apparatus that includes Zener diodes and photocouplers to limit the potential difference between the helix and anode electrodes, using transistors and capacitors to control the circuit, allowing for reduced current flow through the helix electrode during voltage application and maintaining optimal anode voltage levels without the need for high-pressure vacuum relays.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high-voltage transistors and vacuum relays are used to control anode voltage, then the potential difference between anode and cathode can be controlled, but the device complexity and cost increase significantly
Solution Approach 1:
The patent introduces Zener diodes as intermediary components between the anode and helix electrodes to automatically limit the potential difference. These diodes act as voltage clamps that prevent excessive voltage differences without requiring complex active control circuits, thereby reducing device complexity while maintaining reliable voltage control.
Solution Approach 2:
The control circuit uses the existing helix voltage as a reference to automatically regulate the anode voltage through Zener diodes. The system self-regulates by comparing anode voltage against helix voltage and using the Zener breakdown characteristic to maintain appropriate potential difference, eliminating the need for external high-voltage transistors and vacuum relays.
2Reliability
If high-voltage transistors are used to control anode voltage, then potential difference can be limited, but power consumption increases
Solution Approach 1:
The Zener diodes provide passive voltage limiting that consumes minimal power compared to active high-voltage transistor control. The diodes automatically clamp the voltage when exceeded, requiring no external control signals or continuous power supply to the control elements, thereby significantly reducing power consumption while maintaining protection functionality.
3Reliability
If expensive vacuum relays are used to control anode voltage, then voltage application can be controlled, but the cost increases
Solution Approach 1:
The patent replaces expensive vacuum relays with inexpensive Zener diodes that provide equivalent voltage control functionality. The Zener diodes are solid-state components with long operational life and low cost, making the system economically viable while maintaining reliable control over voltage application to the anode electrode.
4Productivity
If potential difference between anode and cathode is not limited, then electrons can flow freely, but overcurrent flows through helix electrode causing damage
Solution Approach 1:
The patent converts the potentially harmful effect of uncontrolled electron flow into a beneficial protective mechanism. By using Zener diodes to establish a controlled potential difference, the system allows sufficient electron flow for normal operation while simultaneously preventing excessive current that would damage the helix electrode. The voltage limitation becomes a protective feature rather than a restriction.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively reduces current flow through the helix electrode during helix and collector voltage rises, preventing damage and maintaining maximum gain in normal operation while using low-cost general-purpose parts, thus reducing power consumption and eliminating the need for expensive relays.
Implementation Method 1
a Zener diode connected between the helix electrode and the anode electrode for limiting a potential difference applied to the helix electrode and the anode electrode to within a Zener voltage
Implementation Method 2
a photocoupler having a photodiode at an input end thereof and a phototransistor at an output end
Data Source
AI summary
The present invention includes a Zener diode connected between a helix electrode and an anode electrode, a transistor that closes or opens a circuit between a cathode and an anode of the Zener diode, a photocoupler for turning ON/OFF the transistor through a phototransistor, a first switch for supplying or cutting off a DC voltage for the photodiode of the photocoupler, a capacitor to which the DC voltage that is to be supplied to the photodiode is applied and a control unit that turns ON the first switch beforehand to apply a DC voltage to the photocoupler and the capacitor and that turns OFF the first switch simultaneously with an application of a helix voltage.