AC Voltage Detection Circuit with Merged Discharge Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional capacitor discharge circuits for alternating-current power lines are bulky due to multiple time-constant circuits and resistive voltage detection, leading to increased size and standby power consumption.
Innovation Solution
A capacitor discharge circuit utilizing a parallel-connected capacitor with a rectification element, diodes, and capacitors in series with a ground terminal for voltage detection, along with a timer to manage discharge operations, reducing the need for resistive components and enabling a compact design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple time-constant circuits and resistive voltage detection are used in conventional capacitor discharge circuits, then reliable voltage detection and discharge control are achieved, but the circuit size increases and standby power consumption increases
Solution Approach 1:
The patent combines multiple time-constant circuits into a single time-constant circuit by using a capacitor that is charged through different resistance paths (first and second resistance elements) depending on the voltage polarity. This merging reduces the number of separate circuits and components, thereby reducing circuit size while maintaining the reliability of voltage detection across both positive and negative half-cycles of the AC voltage.
Solution Approach 2:
The patent employs a universal voltage detection mechanism where a single capacitor and time-constant circuit serve dual purposes for detecting both positive and negative half-cycles of the AC voltage. The circuit uses switching elements to alternately connect the capacitor through different resistance elements, allowing the same detection circuitry to function universally for both polarity conditions, thus reducing overall circuit complexity and size.
2Reliability
If multiple time-constant circuits and resistive components are used in conventional capacitor discharge circuits, then adequate discharge control is achieved, but standby power consumption increases due to resistive losses
Solution Approach 1:
The patent merges multiple discharge control functions into a single control mechanism that uses one capacitor and one time-constant circuit to control the discharge of the AC voltage capacitor during both positive and negative half-cycles. By eliminating redundant resistive components and time-constant circuits, the total resistive losses are reduced, thereby lowering standby power consumption while maintaining reliable discharge control.
Solution Approach 2:
The patent extracts and eliminates unnecessary resistive components from the conventional circuit design. Instead of having separate resistance elements for each time-constant circuit, the invention uses a minimal set of resistance elements shared by the unified time-constant circuit, thereby removing excess resistive losses that contribute to standby power consumption while preserving the essential discharge control function.
3Measurement precision
If conventional capacitor discharge circuits are designed with multiple time-constant circuits, then comprehensive voltage detection is achieved, but the circuit becomes complex and difficult to integrate into ICs
Solution Approach 1:
The patent combines multiple voltage detection functions into a single integrated circuit structure. By using one capacitor, one time-constant circuit, and switching elements that alternate between different resistance elements, the design achieves comprehensive voltage detection for both half-cycles with minimal components. This merging significantly reduces circuit complexity and facilitates integration into ICs while maintaining measurement precision.
4Measurement precision
If resistive voltage detection is used in conventional capacitor discharge circuits, then voltage detection is achieved, but the circuit size increases
Solution Approach 1:
The patent extracts the essential voltage detection function from the conventional design that uses multiple separate resistive detection circuits. By implementing a single time-constant circuit with a capacitor that is alternately charged through different resistance elements, the invention achieves voltage detection capability with minimal resistive components, thereby reducing circuit size while preserving detection precision.
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 simplifies the circuit, reduces size, and minimizes standby power consumption by eliminating resistive losses, facilitating integration into ICs and preventing electric shocks during power disconnection.
Implementation Method 1
a rectification element that performs full-wave rectification on an alternating-current voltage from the alternating-current power source
Implementation Method 2
a first series circuit including a first capacitor and a second capacitor connected in series between one end of the alternating-current power source and the ground terminal of the rectification element
Data Source
AI summary
An alternating-current voltage detection circuit for detecting an alternating-current voltage from an alternating-current power source according to one or more embodiments may include: a rectification circuit that performs full-wave rectification on an alternating-current voltage from the alternating-current power source and supplies a rectified output to a load; a series circuit comprising a first capacitor and a second capacitor electrically connected in series between one end of the alternating-current power source and the ground terminal of the rectification element; a discharge circuit that causes the second capacitor to discharge such that an absolute value of dv/dt voltage does not reach a predetermined voltage, wherein the second capacitor is electrically connected to the ground terminal side of the rectification element; and a predetermined period generator that outputs a signal after an elapse of a predetermined period of time from stoppage of a discharge operation of the discharge circuit.