Inductive Charging Inverter Pulse Pattern Modulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inductive charging systems for electric vehicles face inefficiencies due to increasing losses at partial load operations, primarily due to line losses in coils and inverters, which are exacerbated by the need for additional DC/DC converters on the secondary side to manage voltage, leading to weight, space, and efficiency issues.
Innovation Solution
The system employs a switching strategy in the inverter and rectifier devices using pulse pattern modulation, allowing for zero voltage or zero current switching modes without additional impedance converters, thereby optimizing power transmission across all operating points and reducing hardware requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If additional DC/DC converters are installed on the secondary side to manage voltage, then voltage control capability is improved, but device complexity, weight, and installation space increase
Solution Approach 1:
The patent removes the secondary-side DC/DC converter from the system by extracting this component entirely. Instead, voltage control is achieved through primary-side control methods including pulse width modulation (PWM) of the inverter and impedance matching networks, eliminating the need for additional power conversion hardware on the vehicle side.
Solution Approach 2:
The primary-side control system is enhanced to perform multiple functions: it simultaneously manages power inversion, voltage regulation, and impedance matching. The inverter circuit on the primary side is designed to handle both power conversion and voltage control tasks that would traditionally require separate DC/DC converters on the secondary side.
2Adaptability or versatility
If additional DC/DC converters are installed on the secondary side to manage voltage, then voltage control capability is improved, but weight increases
Solution Approach 1:
The patent removes the secondary-side DC/DC converter from the system by extracting this component entirely. Instead, voltage control is achieved through primary-side control methods including pulse width modulation (PWM) of the inverter and impedance matching networks, eliminating the need for additional power conversion hardware on the vehicle side.
3Adaptability or versatility
If additional DC/DC converters are installed on the secondary side to manage voltage, then voltage control capability is improved, but installation space increases
Solution Approach 1:
The patent removes the secondary-side DC/DC converter from the system by extracting this component entirely. Instead, voltage control is achieved through primary-side control methods including pulse width modulation (PWM) of the inverter and impedance matching networks, eliminating the need for additional power conversion hardware on the vehicle side.
4Loss of energy
If line losses in coils and inverters are reduced by optimizing transmission, then efficiency at partial load is improved, but device complexity increases
Solution Approach 1:
The patent implements dynamic impedance matching networks that automatically adjust their characteristics based on the operating conditions (load level, coupling factor). This dynamic adaptation allows the system to optimize power transfer and minimize losses across different operating points without requiring manual intervention or complex additional control systems.
Solution Approach 2:
The system optimizes transmission efficiency by dynamically changing electrical parameters including impedance values, switching frequencies, and pulse widths. These parameter adjustments are made through control circuits that monitor system conditions and modify operating parameters to minimize losses in coils and inverters across various load conditions.
5Power
If switching frequency is increased to improve power transmission, then power transmission capability is improved, but losses and magnetic field emissions increase
Solution Approach 1:
The patent utilizes resonant periodic oscillations in the primary and secondary coils to enable efficient energy transfer. By operating at the resonant frequency of the coupled coils, the system achieves effective power transmission without requiring excessively high switching frequencies, thereby minimizing losses and magnetic field emissions while maintaining good coupling conditions.
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 approach enhances efficiency and reduces losses by minimizing voltage applied to the transmission device, maintaining high efficiency at both full and partial load operations, and allows for operation at higher frequencies with minimal hardware, eliminating the need for additional passive and active components.
Implementation Method 1
the primary coil generates a high-frequency alternating magnetic field that penetrates the secondary coil and induces a corresponding current there
Implementation Method 2
The current flow typically results from the excitation of the oscillating circuit formed by the primary coil and a corresponding compensation capacitance
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
The invention relates to a transmission system for transmitting energy to a load without contact, comprising a transmission device for transmitting electrical energy without contact, an inverter device, which is arranged between an energy source that provides supply power and the transmission device and which is designed to transmit electrical energy from the energy source to the transmission device, a rectifier device, which is arranged between the transmission device and the load and which is designed to transmit the electrical energy from the transmission device to the load, wherein the inverter device is designed to set the amount of the transmitted electrical power by means of pulse pattern modulation of the energy source and/or the rectifier device is designed to set the amount of the transmitted electrical power by means of pulse pattern modulation of power provided by the transmission device. The invention further relates to a method and to a vehicle assembly.