Capacitive coupling through a hydrodynamic journal bearing to power rotating electrical loads without contact

Hagen, Skyler; Knippel, Ryan; Dai, Jufeng; Ludois, Daniel C.

doi:10.1109/wpt.2015.7140181

Cited by 16 publications

(9 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Consequently, power can be transferred to the load without direct electrical contact while allowing some freedom of movement between the primary and secondary plates. The capacitive coupling structure can be of various configurations according to different applications; it may be rectangular, cylinder, disk [15], matrix [16], conformal surface [17], and hydrodynamic capacitive coupling [18], [19]. The receiver unit regulates the captured power and drives the load according to demand.…”

Section: Capacitive Power Transfer Conceptmentioning

confidence: 99%

“…When the system is functioning properly, the loop adjusts the control voltage v c , which drives the phase deviation to zero. Theoretically, the optimum phase ( ref ) for the Class-E resonant inverter is −32.48 [19]. The resonant frequency tracking unit must be able to track the phase difference of the current i l and voltage v d and maintain the phase at −32.48 to yield ZVS operation.…”

Section: Capacitive Power Transfer System With Frequency Tracking mentioning

confidence: 99%

“…For its future development, this system will be applied in rotary applications, such as fluid bearing capacitors and rotating capacitors. Hydrodynamic capacitive coupling is also attractive for such applications [19], as they can provide high coupling capacitance for high power rotary applications, such as slip ring replacement. However, they may have speed-dependent coupling capacitance, and the circuit must be auto-tuned.…”

Section: Capacitive Power Transfer System With Frequency Tracking mentioning

confidence: 99%

See 2 more Smart Citations

Design of Capacitive Power Transfer Using a Class-E Resonant Inverter

Yusop¹,

Saat²,

Nguang³

et al. 2016

Journal of Power Electronics

View full text Add to dashboard Cite

This paper presents a capacitive power transfer (CPT) system using a Class-E resonant inverter. A Class-E resonant inverter is chosen because of its ability to perform DC-to-AC inversion efficiently while significantly reducing switching losses. The proposed CPT system consists of an efficient Class-E resonant inverter and capacitive coupling formed by two flat rectangular transmitter and receiver plates. To understand CPT behavior, we study the effects of various coupling distances on output power performance. The proposed design is verified through lab experiments with a nominal operating frequency of 1 MHz and 0.25 mm coupling gap. An efficiency of 96.3% is achieved. A simple frequency tracking unit is also proposed to tune the operating frequency in response to changes in the coupling gap. With this resonant frequency tracking unit, the efficiency of the proposed CPT system can be maintained within 96.3%-91% for the coupling gap range of 0.25-2 mm.

show abstract

Section: Capacitive Power Transfer Conceptmentioning

confidence: 99%

Section: Capacitive Power Transfer System With Frequency Tracking mentioning

confidence: 99%

Section: Capacitive Power Transfer System With Frequency Tracking mentioning

confidence: 99%

See 1 more Smart Citation

Design of Capacitive Power Transfer Using a Class-E Resonant Inverter

Yusop¹,

Saat²,

Nguang³

et al. 2016

Journal of Power Electronics

View full text Add to dashboard Cite

show abstract

“…Specially, CPT system with row array capacitive coupler has been used in many rotary applications. In [19]- [21], two types of coupling structures, disk and cylinder, for a rotary CPT system application have been proposed. A new CPT technique has been proposed as an alternative to slip rings or rotary transformers in [22].…”

Section: Introductionmentioning

confidence: 99%

A Sleeve-Type Capacitive Power Transfer System With Different Coupling Arrangements for Rotary Application

et al. 2020

IEEE Access

View full text Add to dashboard Cite

This paper presents a sleeve-type capacitive power transfer (CPT) system for contactless rotary applications. Sleeve-type capacitive couplers with different coupling arrangements between primary and secondary metal sleeves are proposed in this research, which lead to different coupling characteristics with positive, zero, and negative coupling coefficients. The effect of coupling coefficient variations caused by both the power transfer distance and the ratio between the overlapping length and the height of outer sleeves is analyzed. Combining the sleeve-type coupler, the CPT system is developed with a double-sided LCcompensated network and half-bridge inverter. For the CPT systems with positive and negative coupling coefficients, parameter design methods are presented to determine system parameters to achieve zero phase angle (ZPA) condition under the same output power. Then overall system performances of the CPT systems with local maximum positive and local minimum negative coupling coefficients are analyzed and compared by simulation in MATLAB/Simulink and Maxwell. Finally, an experimental prototype is constructed, which has demonstrated a power efficiency of 85.3% at 100.8 W. Simulation and experimental results show that the CPT system with local minimum negative coupling coefficient has clear advantages in increasing transfer distance, reducing voltage on sleeves, suppressing fringing electric field, and improving power density.INDEX TERMS Wireless power transfer, capacitive power transfer, sleeve-type capacitive coupler, negative coupling coefficients.

show abstract

“…According to the transmission medium, the WPT system is mainly categorized into four types: electromagnetic induction [17][18][19], magnetic resonance coupling [20,21], electric field coupling [22,23], and electromagnetic wave [24][25][26]. Besides, ultrasonic [27] and lasers [28] are also used.…”

Section: Introductionmentioning

confidence: 99%

A Method of Estimating Mutual Inductance and Load Resistance Using Harmonic Components in Wireless Power Transfer System

et al. 2019

View full text Add to dashboard Cite

In general, for the WPT (Wireless Power Transfer) system, as the mutual inductance and load resistance are calculated according to the measured data of both the transmitter and receiver, the wireless communication modules are needed to share data. A method for estimating mutual inductance and load resistance without wireless communication is proposed, based on the fundamental and third harmonic components. The circuit is decomposed with respect to the frequencies, by which the mathematic model is established. The fundamental and harmonic components of the output voltage and current of a high-frequency inverter are found by FFT (Fast Fourier Transform). The experimental WPT system with a SiC power MOSFET is designed, and the effectiveness of the proposed method is verified by the simulation and experiment results. Additional hardware and frequency scanning operation are not needed because of the use of the harmonic components.Generally, the Magnetic Resonance Coupling Wireless Power Transfer (MRC-WPT) system consists of three parts, namely a high-frequency power supply, a coil set (transmitting and receiving coil; some systems may have more than one intermediate coil in the coil set), and a receiver circuit. The coupling coefficient (or mutual inductance) between the coils and the load resistance are directly related to the performance of the system (for example, efficiency, transfer power, etc.) [29][30][31].The measured data of the load voltage and/or current of the receiver are transferred to the transmitter through wireless communication, and these data take part in realizing the constant current, constant voltage, or constant power of the load.In [32,33], the methods for keeping the constant voltage of the load were represented using the communication module. In [34], the method for maintaining the constant voltage and the current of the load was realized using the communication module. It was implied that the relative position between the transmitter and the receiver moved infrequently, and the internal resistance of the battery was very slowly changed when charging the battery of an electric vehicle, then the concept of the weak communication was defined. In spite of the communication environment being unstable, the load resistance and mutual inductance could be derived, but the communication function was not completely removed from the system. Due to the use of the wireless communication module, the power consumption may be increased, and the normal communication function cannot be performed in some severe situations. It is more unacceptable that if only one of the communication modules among the transmitter and the receiver is damaged, the whole WPT system cannot be operated. In [35], a method in which power and data were transferred at the same time through only one coil was proposed.If the load voltage and/or current can be estimated without any measured data of the receiver, the difficulties mentioned above do not need to be considered; while, if the inductance and capacitance of the receiver (L 2 , C ...

show abstract

Capacitive coupling through a hydrodynamic journal bearing to power rotating electrical loads without contact

Cited by 16 publications

References 6 publications

Design of Capacitive Power Transfer Using a Class-E Resonant Inverter

Design of Capacitive Power Transfer Using a Class-E Resonant Inverter

A Sleeve-Type Capacitive Power Transfer System With Different Coupling Arrangements for Rotary Application

A Method of Estimating Mutual Inductance and Load Resistance Using Harmonic Components in Wireless Power Transfer System

Contact Info

Product

Resources

About