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The resonance circuit's design has a major influence on the inductive electric vehicle (EV) charging system's performance and the distance between the primary and secondary inductive coils. If resonance circuitry is not included in an inductive power transfer (IPT) system, its performance suffers dramatically and its power transfer efficiency suffers significantly. Furthermore, the design of the resonance circuit has a major impact on the rating as well as the voltage and current strains on the semiconductor switches. The sequence, amplitude, and shape of the waveform are determined by the configuration of the energy storage components. The arrangement of these components is critical in defining how the inductive power transfer system behaves and operates. A few popular architectures play an important role in shaping how the system works. In this paper, the significance and effect of resonance circuits on the inductive charging of electric vehicles have been reviewed and discussed comprehensively. Furthermore, a detailed discussion was presented for the second-order resonance circuit, the higher-order resonance circuit, and the hybrid resonance circuit. Additionally, H-bridge resonant inverter topology was discussed and three main resonant architectures for the H-bridge inverter were studied inclusively. They include the inductor-capacitor-inductor (LCL) resonance architecture, switched inductor-capacitor (SLC) resonance architecture, and High-gain resonance architecture. Also, a comparison of these architectures was done and represented in tabular form. Lastly, an analysis of the effect of frequency variations in the resonant circuit architectures. [ABSTRACT FROM AUTHOR]

A new series-type hybrid circuit breaker (S-HCB) concept for dc fault protection is reported that is fundamentally different from other prior-art hybrid circuit breakers (HCB) or solid-state circuit breakers (SSCB) in the literature. The S-HCB conducts its load current through metal wires instead of power semiconductor switches and curtails its fault current to near zero throughout the entire opening process of a series mechanical switch. It offers the low on-resistance of the conventional mechanical contacts for normal operation and µs-scale fault response even faster than the fast-acting SSCBs. A proof-of-concept S-HCB prototype experimentally demonstrates the interruption of a fault current of 30 A within 10 μs at a dc voltage of 600 V. The operating principle, simulation, and experimental results are discussed in this letter. [ABSTRACT FROM AUTHOR]

Hybrid dc circuit breakers (HCBs) are recognized as suitable devices for protecting high-voltage direct-current (HVDC) systems, along with other dc circuit breakers (DCCB). However, compared to mechanical circuit breakers, HCBs exhibit higher conduction losses. Such losses are inevitable under no-fault conditions as current may flow through some of the semiconductor switches. An integrated circuit breaker (ICB) minimizing these losses is presented in this paper, and this is achieved by replacing semiconductor switches by mechanical components in the current path. For completeness, the topology design, operating sequence and a mathematical analysis for component sizing of the device are provided. In addition, an estimation of the conduction losses is quantified. It is estimated that the power losses of an ICB are 2 to 30% of an HCB only. The ICB has been implemented in PSCAD/EMTDC to demonstrate its effectiveness for isolating dc faults, with simulations conducted on a three-terminal HVDC grid. [ABSTRACT FROM AUTHOR]

Long pulse gas lasers utilizing double-discharge circuits are different from the single-short pulse gas lasers in that they do not require all of the desired energy to be deposited into the peaking capacitors prior to ignition of the main gap. Instead, the majority of the energy is held in another capacitor that is then discharged in the form of a longer duration discharge pulse output compared with that of single-short pulse lasers. Extended stability of the discharge is typically achieved by igniting the main gap discharge at higher ignition voltages. Several double-discharge circuit topologies exist in the literature. However, each topology has its own disadvantages primarily centered around the components needed and the resulting complexity. In this article we introduce the application of the new hybrid circuit pulsed power topology as a double-discharge circuit with high ignition voltages. The hybrid circuit pulsed power topology was originally published by the authors of this article in their previous publication titled “A New Hybrid Pulsed Power Circuit Topology for Gas Laser Applications.” The advantage of the hybrid circuit as a double-discharge circuit is that it does not require any special device [e.g., semiconductor opening switch (SOS) diode] and can use commonly available components. [ABSTRACT FROM AUTHOR]

DC system has the potential of vast and rapid fault current generation due to multiple (line and converters) discharge capacitors and small impedance of DC lines. DC fault current spreads through the system exponentially compared to AC. Such an unexpected huge current causes a voltage drop, impacts the normal operation of system components and exposes the system to a great challenge for fault detection and interruption. For prevention of system destruction during the fault, multiple approaches such as application of Mechanical Circuit Breakers (MCBs), fuses, Solid State Circuit Breaker (SSCB), and Hybrid Solid-State Circuit Breaker (HSSCB) have been proposed and applied. In DC fault applications, fast fault detection and interruption without any interference to the other components are quite important. Therefore, semiconductor breakers have been implemented to meet the DC fault protection requirements with a high-speed operation where traditional MBs have failed. Due to the high conduction loss and low efficiency of semiconductor switches, for fast and efficient DC fault interruption, different Fault Current Limiter (FCL) types are suggested. Although a high impedance FCL can prevent the voltage fluctuations due to the current decline, it can cause operation speed issues, coordination troubles, overheat, and malfunction of protective components in a fault situation. This paper focused on a combination of two-way HSSCB with a self-adapt DC short current limiter, ultra-fast switch, and power electronic switch to overcome the above challenges. It can efficiently and fast fault current limiting response with low conducting loss and appropriate cooperation among protective components in a low voltage DC system. The MATLAB/Simulink is used to analyze the effectiveness and consistency of the proposed FCL-HSSCB in 400 V interconnected standalone DC microgrids. [ABSTRACT FROM AUTHOR]

This article presented a new hybrid circuit breaker solution for using in dc microgrids. The proposed solution can offer a high-reliability protection feature for the dc microgrid with low conduction loss, bidirectional current flow, and galvanic isolation function. In the design, it is combined with a group of mechanical switches and semiconductors, where the mechanical switches handle the current conduction during normal operation and the semiconductors handle the breaker response during transient operation. The design fully utilizes the advantage of both types of switches and maximizes the performance and life time of the system. Throughout the design, it maintains only one mechanical switch in series with each power line; thereby, the high conductivity of the circuit breaker is maintained. At the same time, through the hybrid design, the electrical stress applied to the mechanical switch is eliminated. Thus, an effective and high-reliability solution is provided for the design of dc circuit breakers. The operation principle is explained in detail and the design guideline is provided. A 150/380 V and 15 A circuit breaker is successfully implemented, and the performance is experimentally verified, which shows good agreement with the theoretical findings. [ABSTRACT FROM AUTHOR]

Hybrid dc circuit breaker (HCB) is currently the most promising dc circuit breaker. However, since it requires hundreds of semiconductor switches to withstand high transient interruption voltage, the implementation cost is high. Besides, in the multiterminal dc grid, three or more HCBs may be required at a dc bus, which worsens the disadvantages of HCBs in economy and volume. In order to solve this problem, this article designs a diode-bridge multiport HCB (DB-MPB) with its control procedures. By integrating the n HCBs at the dc bus to a single n-port HCB, the number of semiconductor switches and the footprint can be reduced, while the good current interruption performance can be still maintained. Besides, for the possibility of ultrafast disconnector (UFD) failure, the proposed DB-MPB has the function of UFD failure protection. The effectiveness of the designed DB-MPB under different scenarios is verified by simulations and experimental tests. In addition, the performance comparisons in economy and functionality of the proposed DB-MPB with existed solutions are presented to highlight the advantages of the proposed solution. [ABSTRACT FROM AUTHOR]

Direct current (DC) circuit breakers are a key enabling technology for fault management in multiterminal highvoltage DC (HVDC) systems. DC fault isolation is challenging due to the high rate of rise of the fault current and the lack of natural current zero-crossings found in ac systems. In this paper, we present a novel superconducting hybrid dc circuit breaker that utilizes the intrinsic characteristics of the superconductor material. The automatic quench of the superconductor coil as a result of a high fault current transfers the current from the mechanical switch to the semiconductor switch. The isolating mechanical switch is able therefore to open at low current and recover its dielectric capability rapidly. A low voltage DC circuit breaker prototype has been built using a multistrand magnesium diboride (MgB2 ) coil, a vacuum interrupter, and an insulated-gate bipolar transistor module. This prototype successfully demonstrated interruption of 500 A DC within 4.4 ms. This paper presents the design of the superconducting hybrid breaker prototype and a detailed analysis of the experimental results. This superconducting hybrid dc circuit breaker has significant potential for scaling up the high-voltage and high-current applications. [ABSTRACT FROM AUTHOR]

The ultra-fast switching of power MOSFETs, in about 1 ns, is very challenging. This is largely due to the parasitic inductance that is intrinsic to commercial packages used for both MOSFETs and drivers. Parasitic gate and source inductance not only limit the voltage rise time on the MOSFET internal gate structure but can also cause the gate voltage to oscillate. This paper describes a hybrid approach that substantially reduces the parasitic inductance between the driver and MOSFET gate, as well as between the MOSFET source and its external connection. A flip-chip assembly is used to directly attach a die-form power MOSFET and driver on a PCB. The parasitic inductances are significantly reduced by eliminating bond wires and minimizing lead length. The experimental results demonstrate ultra-fast switching of the power MOSFET with excellent control of the gate-source voltage. [ABSTRACT FROM AUTHOR]

With the advent of direct current (DC) loads such as LED lighting, IT equipment, electric vehicles, and DC powers generated from renewable energy sources, low voltage DC (LVDC) distribution system is becoming a hot issue. One of the hurdles in the LVDC distribution system is arc flash at the contact points that occurs during the circuit is opening. Unlike alternating current, direct current has no zero points and sustains constantly. Therefore, there is a risk of electric fire due to continuous generating arcs when the load current is interrupted with an existing electrical contact type circuit breaker. Recently, the concept of a hybrid circuit breaker that takes advantage of traditional electrical contact type switch and the arcless semiconductor switch has been proposed, but how to cooperatively operate the two switches has become an issue. This paper analyzes the principle of a hybrid circuit breaker for blocking LVDC current and proposes a gate drive controller for it. Through 400V class LVDC cutoff test, the operation of the proposed hybrid circuit breaker is verified and the characteristics are analyzed. [ABSTRACT FROM AUTHOR]

• Hybrid DC circuit breaker with coupled inductor enables automatic current commutation. • The current commutation is faster when the rate of rise of the fault current is higher. • Flexibility in the design of the coupled inductor for current commutation. • The prototype has successful interrupted 200 A DC current within 4 ms. • Very low operating loss hybrid DC circuit breaker topology. HVDC transmission systems using voltage source converters (VSC-HVDC) have been identified as an attractive solution for bulk power delivery over long distance. However if DC grids are to be built using this technology, fast DC circuit breakers are needed. This work proposes a new hybrid DC circuit breaker utilizing a series connected coupled inductor connected, which enables automatic current commutation from the mechanical switch to the semiconductor switch during a fault. The key advantage of the proposed DC circuit breaker is that the current in the mechanical switch automatically reduces to zero when a fault happens. This paper focuses on comparison of different mechanisms to commutate the current from the mechanical switch to the semiconductor switch and create a zero current for the mechanical switch. Three types of hybrid DC circuit breaker topologies including proactive hybrid DC circuit breaker, hybrid DC circuit breaker with commutation booster, and hybrid DC circuit breaker with coupled inductor for a 500 kV HVDC system are simulated and compared using Matlab/Simulink. A prototype hybrid DC circuit breaker with coupled inductor is designed and built. The prototype is capable of interrupting 200 A direct current within 4 ms. The automatic current commutation compensates for the fault detection and location time in the selective protection scheme, which provides faster fault current interruption. [ABSTRACT FROM AUTHOR]