Solar-powered, wireless vehicle charging system with automatic alignment

Abstract

A wireless vehicle charging system consisting of a solar-powered, tracking photovoltaic unit with an irradiance sensor and a motorized actuator, a power conditioning stage and an energy storage unit, a ground unit with a resonant transmitting coil, a vehicle unit with a receiving coil and a control unit configured to coordinate presence detection, orientation check, safety interlocks and wireless power transfer for charging a vehicle battery.

Description

AREA OF INVENTION

[0001] The invention relates to charging systems for electric vehicles, in particular devices that combine solar tracking, energy storage, vehicle presence detection, standardized alignment of wireless energy transmission and resonant inductive charging for private and commercial use. BACKGROUND OF THE INVENTION

[0002] Wireless charging promises a seamless user experience for electric vehicles, eliminating the need for plugging in. However, practical application requires efficient coupling despite misalignment, robust safety and foreign object detection, and interoperability according to recognized standards to ensure reliable operation under varying conditions. Until now, alignment has been a significant hurdle. The SAE J2954 framework now defines a common methodology, the Differential Inductive Positioning System (DIPS), to guide vehicles into optimal coupling zones and verify alignment before power transfer. This accelerates commercialization and interoperability between different providers. Integrating on-site renewable energy sources further enhances sustainability.Solar tracking increases energy yield compared to fixed solar installations through simple light sensors and motorized actuators that follow intensity peaks. Local storage acts as a buffer for intermittent power generation during charging. A combined architecture that integrates solar tracking, energy storage, presence and orientation detection, and resonant inductive power transfer enables efficient and user-friendly charging with reduced grid dependency and is compatible with evolving standards for wireless charging of light electric vehicles. SUMMARY OF THE INVENTION

[0003] The invention relates to a wireless vehicle charger comprising a solar-powered, tracking photovoltaic system with an irradiance sensor and a motorized actuator, a power conditioning and energy storage module, a wireless ground charger with a resonant transmitting coil, a vehicle with a receiving coil, proximity detection via ultrasonic or equivalent sensors, and a controller. This controller coordinates the orientation according to standardized procedures, safety interlocks, and energy management for the solar system, storage, and consumers. During operation, the irradiance sensor aligns the actuator so that the solar panel receives maximum sunlight and a battery buffer is charged. As soon as a vehicle is detected and the orientation confirmed, the controller activates the transmitting coil and regulates the power flow based on coupling parameters, coil temperatures, and the state of charge of the vehicle battery.The status is transmitted to a user interface or a mobile application. DETAILED DESCRIPTION

[0004] The device comprises a housing containing a photovoltaic module, a motor-driven, single- or dual-axis tracking mechanism, and an irradiance sensor (e.g., an LDR) to determine solar radiation. A control loop positions the module for optimal energy yield and activates wind-saving driving modes in unfavorable conditions. The PV module's current is fed via a DC / DC converter into a battery storage system designed to handle expected peak loads and daily fluctuations. The energy storage system reduces short-term grid draw and stabilizes the charging station's output under partial shading. A vehicle detection system uses an ultrasonic sensor to detect arrival within a defined area. This triggers pre-charge checks and initiates alignment assistance, positioning the vehicle within a coupling zone compatible with the wireless charging station.The ground unit consists of a resonant transmitting coil driven by a high-frequency inverter and matching network, as well as foreign object detection and temperature measurement. The vehicle unit includes a receiving coil, matching components, and a rectifier circuit to supply power to the interface with the electric vehicle battery. The controller operates according to the alignment procedures specified in SAE J2954, including DIPS signaling. Weak magnetic fields from the ground unit are evaluated by the vehicle system for precise positioning before power transfer is activated. This ensures cross-manufacturer compatibility and operation in all weather conditions. Safety interlocks require successful alignment confirmation, the absence of metallic foreign objects, permissible coil temperatures, and vehicle release before the loading platform is activated.Continuous monitoring adjusts inverter output to maintain resonance and efficiency within tolerances for misalignment. Energy management prioritizes available solar power, utilizes battery storage to cover peak loads or during periods without sunlight, and can optionally coordinate with the grid using time-of-use tariffs to reduce costs while maintaining charging pad performance. A communication interface connects the controller to a mobile application or local display, showing real-time charging status, energy mix (solar vs. storage), estimated charging time, and historical energy data. Firmware updates are supported to accommodate changes in wireless charging standards and alignment protocols.The mechanical design allows for outdoor installation with environmental protection, maintenance access for power electronics and coils, and mounting fixtures for precise positioning of the charging pads in relation to the parking geometry. Markings facilitate manual alignment when no standardized specifications are available. The architecture supports scalability through the addition of PV capacity, storage modules, and multiple charging pad outputs, and is compatible with future standard extensions for dynamic or wireless high-power transmission. This enables future upgrades without fundamental redesign. The system thus integrates solar tracking and storage with standardized wireless power transmission and automatic vehicle recognition. The result is a robust and efficient charging experience with minimal user intervention and improved use of renewable energy.

Claims

[1] A wireless vehicle charging system comprising a solar-powered, tracking photovoltaic unit with an irradiance sensor and a motorized actuator, a power conditioning stage and an energy storage unit, a ground unit with a resonant transmitting coil, a vehicle unit with a receiving coil and a control unit configured to coordinate presence detection, orientation checking, safety interlocks and wireless power transfer for charging a vehicle battery. [2] System according to claim 1, wherein the controller implements an alignment methodology that is consistent with the SAE J2954 framework and uses the signaling of the Differential Inductive Positioning System to control vehicle positioning and enable energy transfer after alignment has been achieved. [3] System according to claim 1, wherein the irradiance sensor comprises a light-dependent resistor and the actuator enables single- or dual-axis tracking to maximize solar energy uptake and charges the energy storage unit for buffered wireless charging. [4] System according to claim 1, wherein the safety functions include foreign object detection, coil temperature monitoring and power reduction in case of misalignment, and the communication interface provides real-time status and firmware updates for compatibility with evolving wireless charging standards.