Inverter Resonance Circuit Control for Light-Load Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inverter circuits experience decreased efficiency when operating at light loads due to excess energy consumption in the resonance circuit, counteracting the reduction in switching loss achieved through partial resonance.
Innovation Solution
An inverter device with a detection unit to monitor load conditions, stopping the resonance circuit when the load falls below a predetermined threshold, and increasing the carrier frequency to enhance efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the resonance circuit operates to decrease switching loss in the inverter circuit, then switching loss decreases, but overall efficiency decreases when load is light because consumption energy in the resonance circuit exceeds consumption energy in the inverter circuit
Solution Approach 1:
The patent applies dynamics by making the resonance circuit operation status changeable based on load conditions. The control unit dynamically switches the resonance circuit between operating and non-operating states according to the detected load magnitude, allowing the system to adapt to varying operational requirements and optimize performance across different load scenarios
Solution Approach 2:
The patent changes the operational parameter of the resonance circuit from a fixed state to a variable state controlled by load conditions. By adjusting the operation status parameter of the resonance circuit based on detected load values, the system optimizes the balance between switching loss reduction and overall energy efficiency across different operating conditions
2Loss of energy
If the resonance circuit operates continuously to maintain low switching loss, then switching loss remains low, but energy consumption increases under light load conditions
Solution Approach 1:
The system dynamically adjusts the resonance circuit operation based on real-time load detection. The control unit changes the operational state of the resonance circuit from continuous operation to conditional operation, making the energy consumption variable rather than fixed, thereby reducing waste during light load periods
Solution Approach 2:
The system uses its own detection capability to monitor load conditions and automatically control the resonance circuit operation. The inverter device self-regulates by having the control unit detect load magnitude and independently decide whether to operate the resonance circuit, eliminating the need for external control and enabling automatic optimization
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
Improves overall efficiency by optimizing energy consumption and reducing switching losses in inverter circuits, especially at light loads, using wide band gap semiconductors and adjusting the resonance circuit operation.
Implementation Method 1
PTL 1 (Japanese Unexamined Patent Application Publication No. H8-149854) teaches zero current switching or zero voltage switching using partial resonance
Implementation Method 2
the switching element in the inverter circuit is a wide band gap device including a wide band gap semiconductor of silicon carbide (SiC) or gallium nitride (GaN)
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An issue to be solved in the present disclosure is to improve efficiency of an inverter including a resonance circuit and an inverter circuit under a light load. Although a switching loss in an inverter circuit (26) decreases as a resonance circuit (25) operates, efficiency decreases conversely since, when a load applied to the inverter circuit (26) becomes equal to or lower than a predetermined value, consumption energy in the resonance circuit exceeds consumption energy in the inverter circuit (26). Therefore, in this inverter device (100), operation of the resonance circuit (25) is stopped when a load is equal to or lower than the predetermined value to improve the efficiency of the inverter device (100) as a whole.