Inverter Excitation Research Articles

Analysis of high‐frequency electromagnetic ringing phenomenon under GaN‐FET inverter excitation

AbstractIn this study, the ringing phenomenon of gallium nitride‐field effect transistor (GaN‐FET) and silicon‐insulated gate bipolar transistor (Si‐IGBT) inverter excitations in a ring sample was thoroughly measured and analyzed by using a high‐quality oscilloscope with a very high sampling rate of 5 giga‐samples per second (GS/s). Owing to the rapid switching of the GaN‐FET power devices in several nanoseconds and the ringing frequencies in the MHz range, the use of the high sampling rate of 5 GS/s is necessary and useful for accurate measurement. The experimental findings and analysis reveal the following three key points: (i) there are two possible types of high‐frequency resonance phenomena, that is, the first one caused by semiconductor devices and circuits and the other generated by the resonance with loads in use. (ii) The ringing phenomenon because of the resonance under the load is considered to be due to the rising time of pulses that are caused by the rapid switching of the semiconductor devices. (iii) The ability to measure and the two types of ringing phenomena depends on the intensity of the white noise of the measuring instrument

Reduction of MHz Electromagnetic Ringing Losses in Magnetic Materials under GaN Inverter Excitation using Low-Pass Filter

Reduction of MHz Electromagnetic Ringing Losses in Magnetic Materials under GaN Inverter Excitation using Low-Pass Filter

Experimental study of mutual effects of high carrier frequency, dead-time and control sample time on IPMSM core loss under SiC inverter excitation

This paper experimentally analyzes the core loss characteristics of an interior permanent magnet synchronous motor (IPMSM) excited by a SiC inverter with the sinusoidal pulse-width modulation (PWM) and high modulation index of 1.1 considering the mutual effects of the high carrier frequencies of up to 200 kHz, different dead-times of 250 and 1000 ns, control sample times of 100–1000 μs, and stator core temperature. The experimental IPMSM drive system is operated in load condition with a torque of 1.05 Nm and rotational velocity of 1500 rpm. Furthermore, the ringing phenomenon and rise time in the motor voltage are measured and analyzed using a high-resolution oscilloscope that has a superior sampling rate of up to 5 giga-samples per second (GS/s), which helps to thoroughly examine the impact of the SiC inverter excitation on the motor core loss. The relations of the total harmonic distortion (THD) of the measured motor voltage and current and the distortions in the magnetic flux density through the stator core to the IPMSM core loss properties are also evaluated. Lastly, explanations and insights based on physics of the obtained results are presented.

Effect of Laminated Core Body Size on Motor Magnetic Properties

The magnetic characteristics of electromagnetic steel sheets used for motors are evaluated under ideal sinusoidal excitation. However, in actual equipment driving, excitation by pulse-width modulation (PWM) waves is the mainstream method. Therefore, it is necessary to clarify how the magnetic properties used in motors are changed by sinusoidal excitation and inverter excitation. To clarify the magnetic properties of the laminated core by inverter excitation, samples with different core sizes were prepared and the effects on the magnetic properties were then investigated. The magnetic properties were measured by changing only the input voltage VDC while maintaining the carrier frequency and modulation factor constant. As the results, the iron loss values of the small, medium, and large samples with inverter excitation were 6.05, 9.58, and 11.62 W/kg, respectively. The iron losses of the small, medium, and large toroidal cores with inverter excitation increased by 124.9, 256.1, and 332.0%, respectively, compared with the iron loss of each toroidal core with sinusoidal excitation. The larger the body, the higher the required voltage and iron loss. It can be inferred that a larger amount of energy was required to excite a larger toroidal core. This was because the change in magnetic flux density per unit time of the large toroidal core was greater than that of other cores. This indicates that the large toroidal core generated larger eddy currents than other cores. Therefore, it is possible to say that large toroidal cores generate greater eddy current losses than other cores.

Iron loss evaluation method for SiFe sheet material under PWM inverter excitation

This study proposed an iron loss evaluation method for SiFe sheet material under high-frequency current ripple caused by pulse width modulation (PWM) inverter switching. The PWM inverter switching results in dynamic minor loops on the BH plane, leading to iron loss. Furthermore, in magnetic material with wide major loops, such as SiFe sheet material, the iron loss caused by one dynamic minor loop differs based on the flux density bias difference even for the same magnetic field bias. A previous study reported an iron loss calculation error because the conventional iron loss calculation method neglected the iron loss of the flux density bias characteristic in the same magnetic field bias. Therefore, we modified the previously developed iron loss measurement system to collect the iron loss of the flux density bias characteristic and proposed an iron loss calculation method for SiFe sheet material.

Application of square-wave inverter in excitation system for magnetic nanoparticle tomography

To collect the signals of magnetic nanoparticles (MNPs) at a distance from a magnetic nanoparticle tomography, a strong ac magnetic field should be generated by applying a high current to the excitation coil. To this end, sinusoidal excitation using a linear amplifier-type ac power source has been applied to the tomography. Although this source can provide a high-quality sinusoidal voltage, its low power efficiency is not suitable for generating the required high current. To overcome this limitation, we use an H-bridge voltage source inverter to achieve high efficiency by generating a square-wave voltage. However, the third harmonic component in the square wave, undermines the acquisition of MNP signals. Thus, we suppress the third harmonic by shifting the switching phase of the inverter transistors. As a result, the third harmonic in the excitation current is reduced to less than one-tenth of that obtained after conventional suppression. We verify the distribution of MNP signals at depths up to 50 mm using the proposed excitation approach. The results demonstrate the effectiveness of the proposed approach based on square-wave inverter excitation for magnetic nanoparticle tomography.

Iron Loss Evaluation in Consideration of Anomalous Loss for PAM Inverter Excitation in Finite Element Analysis

Iron Loss Evaluation in Consideration of Anomalous Loss for PAM Inverter Excitation in Finite Element Analysis

Iron loss evaluation of magnetic materials excited by a SiC inverter with a Schottky barrier diode wall-integrated trench MOSFET

This study examines the impact of the different diode characteristics on the magnetic hysteretic and iron loss properties of a conventional non-oriented (NO) silicon steel sheet core under silicon carbide (SiC) inverter excitation. We compared the magnetic properties of the magnetic core excited by the inverter using the developed Schottky barrier diode (SBD) wall-integrated trench MOSFET (SWITCH–MOS), which has a low on-voltage Von diode, with those excited by the inverter using a conventional U-shaped trench gate MOSFET (UMOS), which has a body PiN diode with high Von. This study shows for the first time that the shape of the minor loop and iron loss properties depends strongly on only the diode characteristics in the inverter. The iron loss of magnetic materials excited by the SWITCH–MOS inverter with the low-Von diode (i.e., the built-in SBD) was less than that in the case of using the conventional UMOS with a high-Von diode (i.e., the body PiN diode). That is, the SWITCH–MOS with built-in SBD can reduce not only the switching loss, but also the iron loss in magnetic materials such as motor cores.

Iron Loss and Hysteresis Properties of Nanocrystalline Magnetic Materials Under High Frequency Inverter Excitation

Iron Loss and Hysteresis Properties of Nanocrystalline Magnetic Materials Under High Frequency Inverter Excitation

Iron Loss and Magnetic Hysteresis Properties of Nanocrystalline Ring Core at High and Room Temperatures Under Inverter Excitation

Iron Loss and Magnetic Hysteresis Properties of Nanocrystalline Ring Core at High and Room Temperatures Under Inverter Excitation

Iron Loss and Hysteresis Properties of an Amorphous Ring Core at High Temperatures under Inverter Excitation

Iron Loss and Hysteresis Properties of an Amorphous Ring Core at High Temperatures under Inverter Excitation

Representation of Magnetic Hysteresis Phenomena Under Inverter Excitation in a Circuit Simulator Using Coupling Analysis of Electricity and Magnetism

Representation of Magnetic Hysteresis Phenomena Under Inverter Excitation in a Circuit Simulator Using Coupling Analysis of Electricity and Magnetism

Iron Loss and Hysteresis Properties under High-Temperature Inverter Excitation

Iron Loss and Hysteresis Properties under High-Temperature Inverter Excitation

Iron Loss Properties of a Nanocrystalline Ring Core under Si-IGBT and GaN-FET Inverter Excitation

Iron Loss Properties of a Nanocrystalline Ring Core under Si-IGBT and GaN-FET Inverter Excitation

Magnetic Properties of Electrical Steel Sheets with Motor Control Excitation

In this paper, the increment factor of the iron loss by inverter excitation compared with sine wave excitation was clarified using the magnetic hysteresis curve, and change in the parameter which can be understood intuitively was explained. When α (rate of hysteresis curve between the inverter excitation and the sine wave excitation), β (width of the closed loop using inverter excitation around 0 T) and γ (width of the open loop using the inverter excitation around 0.8 T) are increased by the switching operation of the inverter excitation, they increase the area of the hysteresis curve and increase the iron loss compared with the sine wave excitation. On the other hand, the increase factor of the iron loss by the inverter excitation was clarified, and explanation which can be understood intuitively was given. The low modulation factor, the low career frequency, and the high VDC of the inverter are made to increase the factors such as α and β, and increase the area of the magnetic hysteresis curves, and this causes incremental iron loss. Furthermore, α and β are made to fluctuate by the control method of the motor drive using the inverter. That is, the change of the inverter parameters fluctuates the iron loss due to a tradeoff.

Core Loss Properties of a Motor With Nanocrystalline Rotor and Stator Cores Under Inverter Excitation

In this paper, we develop and examine permanent magnet synchronous motors (PMSMs) by use of both stator and rotor cores made of nanocrystalline magnetic materials (NMMs). We report core loss properties of the PMSM with the NMM under inverter excitation. In addition, we compare core losses of the PMSM with conventional non-oriented (NO) steel sheets under inverter excitation to discuss the core loss characteristics of the NMM motor. In average, under inverter excitation, the reduction ratio in core loss of the PMSM made of NMM is about 60% as compared with the core loss of the PMSM with NO sheets. In particular, the average decrease obtained by using NMM rotor core instead of NO rotor core is about 30%.

Influence of Thickness of Non-oriented Electrical Steel on Iron loss under Inverter Excitation

Influence of Thickness of Non-oriented Electrical Steel on Iron loss under Inverter Excitation

Iron Loss and Hysteretic Properties under PWM Inverter Excitation at High Ambient Temperatures

Iron Loss and Hysteretic Properties under PWM Inverter Excitation at High Ambient Temperatures

Influence Rate of Semiconductor ON-Voltage in Inverter Circuit on Iron Loss Inside a Non-Oriented Electrical Steel Sheet

We calculate an iron loss attributed to semiconductors ON-voltages in an inverter circuit and reveal influence rate of the ON-voltages on whole iron loss. In our previous work, it has been revealed by inverter excitation that the ON-voltages make minor loops in magnetic hysteresis of magnetic material and the loops affect iron loss characteristics. In this paper, it is investigated by a factor analysis how much the on-voltage has an influence on iron loss, quantitatively. We separate whole iron loss caused in a non-oriented electrical steel sheet into three losses: loss by the ON-voltage, loss by fundamental component, and loss by inverter carrier. The rates of these losses are evaluated under several conditions of single-phase pulse width modulation inverter excitation, and the results show that the proportion of loss by ON-voltages is up to around 10% depending on inverter excitation parameter: fundamental frequency, carrier frequency, modulation index, and magnetic flux density.

A Practical Core Loss Model for Filter Inductors of Power Electronic Converters

This paper proposes a core loss model for filter inductors of power electronic converters. The model allows a computationally efficient analysis on the core loss of the inductor under the square voltage excitation and the premagnetization condition. First, the core loss of the filter inductor under buck chopper excitation is evaluated with the proposed model and compared with the conventional methods. The comparison shows that the proposed method results in a better core loss prediction under the premagnetized condition than that of conventional alternatives. Then, the core loss of the filter inductor with the pulsewidth modulated inverter excitation is evaluated, which shows that the proposed model not only accurately predicts the core loss but also identifies the hysteresis loss part. These results demonstrate that the approach can further be used for the development of magnetic materials for power electronic applications.