The inductive power transfer (IPT) method is an emerging charging technology that has some advantages over traditional plug-in systems. For example, it is safer, more convenient, and efficient, leading to its widespread acceptance. To design an IPT charger capable of providing a load-independent output, this paper proposes a secondary side-controlled hybrid-compensated topology used in the IPT system to charge the battery with a constant current/voltage output. According to an analysis of the Π-type network, effectively using the existing configuration compensation parameters and adding two AC switches to perform hybrid-topology switching reduces the system’s passive components. Additionally, the proposed IPT charger can easily realize zero-voltage switching. The secondary side-based control omits wireless communication links. Moreover, the control strategy is relatively simple, enhancing the system’s reliability. We designed a 1.4 kW experimental prototype with a 15 cm air gap between the transmitter and receiver to verify the proposed hybrid-compensated IPT system’s feasibility.
This study proposes a novel wireless power transfer (WPT) resonance compensation design method based on the SS topology with a self-limitation function that achieves fault tolerance without additional components when the secondary circuit is in a short and open state. Conventionally, WPT compensation topologies have constant current (CC) or constant voltage (CV) output characteristics. The CC and CV characteristics can lead to overvoltage and overcurrent, respectively. Several control systems have been proposed to counter this issue; however, they tend to increase the cost and weight of the system. The proposed topology has a self-limitation function that limits the voltage–ampere output. Here, the wireless charging system was designed after the parameters were obtained using the proposed analysis. The performance of the proposed design was verified by configuring a 400 W experimental prototype and comparing it with the conventional series–series (SS) topology. Experimental results indicated that the system could effectively limit the output voltage and current resulting from open-or short-circuit states.
This study proposes a full integration method for the double capacitances and inductance–series (LCCL-S)-compensated inductive power transfer (IPT) of electric vehicles (EVs). The transmitter and receiver coils adopt the unipolar coil, and the compensation inductor is designed as an extended DD coil. Specifically, the use of an extended DD coil enhances the misalignment tolerance of the EVs. When the IPT system is in the misaligned state, a primary transfer path for magnetic flux is established between the transmitter and receiver coils, and a secondary transfer path is established between the extended DD coil and receiver coil. The distance between the two unipolar coils of the extended DD coil is optimized to maximize the magnetic flux on the secondary transfer path, thereby increasing the total power of the system misaligned state. Simultaneously, the most suitable turns and inner diameter of the extended DD coil are designed by using the finite element method (FEM) simulation tool. In order to verify the performance of the proposed integrated coil method, a 3.3 kW experimental prototype with a 100 mm air gap was constructed and compared with the conventional integration method under the same conditions. The experimental results show that the proposed magnetic coupling structure maintains at least a 63.6% well-aligned value at a door-to-door 150 mm misaligned state, and the output power of the system is 1.05 kW higher than that of the traditional integration method without extra control algorithms.
27 August 2025 in IEEE Transactions on Industry Applications
Bidirectional inductive power transfer (BIPT) systems provide efficient and contactless power transfer for electric vehicles and other applications. However, practical challenges such as parking misalignment, battery state of charge (SoC) variations, and constraints imposed by the SAE J2954 standard limit their reliability, especially during vehicle-to-grid operation. Existing methods focus mainly on unidirectional charging and often assume ideal alignment, overlooking their applicability to practical operation. This paper proposes a novel BIPT system combining switching-controlled capacitors (SCC) and dualphase-shift (DPS) control to address these challenges. SCC compensates for reactance variations via resonant parameter tuning, while DPS achieves wide input-output gain control to accommodate SoC variations. The integrated approach ensures output characteristics and reliable performance under varying clearance distances and load conditions. A 6.6-kW prototype system was developed and experimentally validated, demonstrating its feasibility and robustness for practical applications.
This paper proposes a medium voltage direct current (MVDC) sensor power supply method based on inductive power transfer (IPT). Given that MVDC distribution networks transmit power at high voltages (several tens of kV), control through sensors is necessary to prevent exacerbating MVDC distribution network accidents. Moreover, these high voltages in MVDC distribution networks mean that high voltage insulation is required between the sensor and the distribution line and for any power supply device electrically connected to the sensor. Therefore, this paper proposes a safe and reliable power supply method using the principle of IPT to maintain a suitable insulation distance between the distribution network and the current sensor supply line. After proposing and designing a transmitter/receiver pad and IPT system by considering the current sensor specifications, a 50-W experimental prototype is developed. The experiments demonstrated that the proposed IPT system can resolve concerns about the breakdown of insulation between distribution networks and power supply lines.
This paper presents an integrated coil design method for inductive power-transfer (IPT) systems. Because a medium-voltage direct current (MVDC) distribution network transmits power at relatively high voltages (typically in the tens of kV), accurate fault diagnosis using high-performance sensors is crucial to improve the safety of MVDC distribution networks. With the increasing power consumption of high-performance sensors, conventional power supplies using optical converters with 5 W-class output characteristics face limitations in achieving the rated output power. Therefore, this paper proposes a safe and reliable power supply method using the principle of IPT to securely maintain the insulation distance between the distribution network and the current sensor-supply line. A 100 W prototype IPT system is investigated, and its feasibility is validated by comparing its performance with conventional optical converters.