Active Damping Circuit for Electric Chopper Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Chopper circuits with existing snubber circuits suffer from poor efficiency due to energy losses during switching, particularly when chopper transistors transition from conductive to non-conductive states, leading to inefficiencies and stress on components.
Innovation Solution
Incorporating an inductive element into the snubber circuit to re-inject energy stored in a capacitive element back into the power supply line, along with a driver transistor to control energy restoration and a protection transistor to prevent power flow anomalies, enhancing energy recovery and reducing switching losses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a traditional snubber circuit with a resistor is used to recover energy during switching, then switching losses are reduced, but the overall circuit efficiency deteriorates due to energy dissipation in the resistor
Solution Approach 1:
The patent recovers energy that would otherwise be dissipated in the resistor by capturing it in a capacitive element during the switching transition, then re-injects it back into the power supply line through an inductive element, thereby recovering rather than discarding the energy
Solution Approach 2:
The patent converts the harmful energy dissipation in the resistor into a beneficial energy recovery mechanism by using the capacitive and inductive elements to capture and return the energy to the power supply, transforming a loss into a recovery opportunity
2Productivity
If the chopping frequency is increased to improve productivity, then output power increases, but switching losses and thermal stress on components increase
Solution Approach 1:
The patent maintains continuous energy recovery and re-injection operation that works effectively across different chopping frequencies, allowing the circuit to benefit from higher frequencies without proportionally increasing switching losses, as the energy recovery mechanism operates continuously alongside the switching cycles
3Use of energy by moving object
If energy is fully recovered and re-injected into the power supply line, then efficiency improves, but current spikes may damage components
Solution Approach 1:
The patent uses the inductive element to cushion and limit the current during energy re-injection into the power supply line, preventing dangerous current spikes while still allowing efficient energy recovery, as the inductor naturally limits di/dt during the energy transfer process
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
This configuration reduces energy losses during switching, allows for increased chopping frequency, and limits current through the inductive element, thereby improving the overall efficiency of the chopper circuit.
Implementation Method 1
an inductive element having a first end connected to a connection point situated between the charging diode and the capacitive element, and a second end connected to one of the lines
Implementation Method 2
a capacitive element and a charging diode for charging the capacitive element
Data Source
AI summary
A snubber circuit for a chopper circuit has at least one chopper transistor with terminals connected to a first line and to a second line, the first line being at a power supply potential and the second line being at ground potential. The snubber circuit has a capacitive element and a charging diode for charging the capacitive element. The charging diode and the capacitive element are connected in series to each other and together they are connected in parallel with the chopper transistor. The snubber circuit has an inductive element having a first end connected to a connection point situated between the charging diode and the capacitive element, and a second end connected to one of the lines.