High Voltage IGBT Research Articles

Electrical Treeing Failure in Silicone Gel Under Positive Repetitive Square Voltage in High-Voltage IGBT Module Encapsulation

Electrical Treeing Failure in Silicone Gel Under Positive Repetitive Square Voltage in High-Voltage IGBT Module Encapsulation

Research on Gate Charge Degradation of Multi-Chip IGBT Modules in Power Supply for Unmanned Aerial Vehicles

In recent years, with the burgeoning application of high voltage in various industrial sectors, the deployment of unmanned equipment, such as industrial heavy-load Unmanned Aerial Vehicles (UAVs), incorporating high-capacity Insulated-Gate Bipolar Transistors (IGBTs), has become increasingly prevalent. The demand for high-voltage IGBT modules in UAV is continuously growing; therefore, exploring methods to predict fault precursor parameters of multi-chip IGBT modules is crucial for the operational health management of unmanned equipment like UAVs. This paper analyzes the gate charge degradation in multi-chip IGBT modules after thermal cycling, which can be used to evaluate the operational state of these modules. Furthermore, to delve into the electrical response of a gate drive circuit caused by local damage within the IGBT module, an RLC model incorporating parasitic parameters of the gate drive circuit is established, and a sensitivity analysis of the peak current in the gate charge circuit is provided. Additionally, in the experimental circuit, an open sample of an IGBT module with partial bond wires lifted off is used to simulate actual faults. The analysis and experimental results indicate that the peak current of the gate charge is closely related to L and C. The significant deviation in the gate current, influenced by the partial bond wires lift-off, can provide a basis for the development of predictive methods for IGBT modules.

Modeling the dVCE/dt and dIC/dt at the Turn-On Transient for High-Voltage IGBTs in the Clamped Inductive Circuit

Modeling the dVCE/dt and dIC/dt at the Turn-On Transient for High-Voltage IGBTs in the Clamped Inductive Circuit

Characteristics and Identification of Partial Discharge for Insulation Structures in High Voltage IGBT Modules Under Positive Square Wave Voltage

Characteristics and Identification of Partial Discharge for Insulation Structures in High Voltage IGBT Modules Under Positive Square Wave Voltage

Transient Analytical Model of High-Voltage and High-Power IGBT Device Based on Nondual Relationship for the Switching Process

This letter focuses on the accurate simulation of the turn- <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> current for high-voltage and high-power IGBT devices and proposes a modeling method of transient analysis model (TAM) for IGBT devices based on the nondual relationship of the switching process. Combined with the structural features of the IGBT chip, the carrier storage effect is analyzed and the analytical expression of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">di</i> / <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dt</i> during the turn- <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> process is corrected. Compared with the existing dual modeling methods, the accuracy of the nondual modeling method for <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">di</i> / <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dt</i> during the turn- <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> process has been greatly improved.

Thermal Imbalance Among Paralleling Chips in Power Modules and the Impact From Traction Inverter System View

In a high-power semiconductor power module where multiple chips are populated in parallel, the thermal imbalance problem arises. In this article, the next-generation standard high-voltage insulated-gate bipolar transistor module for high-speed railcar traction is investigated to characterize the internal thermal imbalance among paralleling chips and evaluate the impact on temperature distribution in field application. The former is accomplished by a new test algorithm with a purposely designed module sample, while the latter is achieved via an advanced electro-thermal simulation from chip level to system level. The experimentally verified thermal network among paralleling chips reveals the multiple reasons for the thermal imbalance. A comparison between the simulation and experimental results regarding the paralleling chips’ power-cycling scenario helps to confirm the effectiveness of the chip model, the thermal network, and the electro-thermal simulation approach. A further electro-thermal simulation shows that the module internal thermal imbalance can lead to significant junction temperature discrepancy among paralleling chips in traction inverter applications, which should be taken into consideration for the long-term reliability assessment.

An Integrated Structure–Material Optimization Strategy for the Packaging of High-Voltage Insulated Gate Bipolar Transistors

High-voltage insulated gate bipolar transistors (IGBTs), such as silicon carbide (SiC)-based ones, are promising as wide bandgap (WBG) power modules. However, current IGBT packaging methods are unsuitable for high-voltage applications due to excessive electric field stress, which increases the risk of partial discharge or electrical breakdown, compromising their insulating property; a new packaging solution is, therefore, needed. In this study, an integrated structure–material optimization strategy through the combination of the finite-element method (FEM) and materials optimization is proposed to reduce the maximum electric field stress ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${E}_{\text {max}}$ </tex-math></inline-formula> ) at the triple junction, i.e., the interface of the ceramic substrate, the metal electrode, and the polymer-based encapsulation, of an IGBT. In epoxy resin encapsulation, it was determined that a symmetrical and chamfered electrode structure with a smooth transition at the triple junction reduces <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${E}_{\text {max}}$ </tex-math></inline-formula> from near 280 to 40 kV/mm at an operating voltage of 27.5 kV. Furthermore, when the permittivities of the substrate (AlN) and encapsulation materials (BaTiO3–resin composites) satisfy an optimal ratio, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${E}_{\text {max}}$ </tex-math></inline-formula> can be further reduced to 34 kV/mm (a 15% decrease). These results indicate that the integrated structure–material optimization strategy effectively enhances the insulating property of the high-voltage IGBTs.

Research on performance parameter degradation of high voltage and high power IGBT module in power cycling test

In Power cycling test, for low-voltage and low-power modules, it is generally considered that the saturation voltage drop VCE(sat) reaches 105% of the initial value or the thermal resistance Rth reaches 120% of the initial value as the basis for judging the failure of the IGBT module. However, since the high-voltage and high-power IGBT modules are connected in parallel with multiple chips, there are differences in the aging speed of the chips, and the degradation of individual chips has little influence on the parameters of the entire module, so the failure judgment standard may not be applicable. In order to obtain the degradation of the characteristic parameters of the high-voltage and high-power IGBT module in the power cycle test, this paper selects the 6500V/600A IGBT module as the research object, adopts the experimental method of constant junction temperature fluctuation, and tests the module parameters after every cycle 20,000 times until the module fails. Three failure modes were found through the test: GE failure, CE failure, GE and CE failure. And the degradation law of the parameters of the high-voltage and high-power IGBT module during the power cycling test was obtained.

Altitude Readiness of High-Voltage IGBTs Subjected to the Partial Discharge at Harsh Environmental Conditions for Hybrid Electric Aircraft Propulsion

The reliability of the insulation of commercially used high-voltage insulated gate bipolar transistor (IGBT) subjected to untimely initiation of partial discharge (PD) at low pressures and high temperatures is investigated and discussed in this letter. To date, no research has addressed the vulnerability of the high-voltage IGBTs to the PDs at harsh environmental conditions for aerospace applications. This letter aims to fill this gap and illustrate the PD characteristics initiated between the electronic components inside the silicone gel. To this end, five commercial 3.3-kV IGBT modules and four 4.5-kV IGBT modules were tested at ac voltage under low pressures (20, 15, and 10 kPa) and high temperatures up to 120 °C. An efficient PD test method and an anti-series connection configuration are suggested, which emulate a realistic operational scenario for IGBTs together with the one suggested by the current standard. Experimental results reveal the occurrence of inconsistent PDs initiating from possible dynamic PD source inside the gel at low pressures, and more intense and consistent PDs when the temperature increases. It is expected the findings highlight the importance of PD tests on IGBTs at the abovementioned operation conditions and provide a selection and modification guidelines of PD-free IGBTs for manufacturers and engineers in the aerospace industry.

A High-Voltage Series-Stacked IGBT Switch With Output Pulse Shaping Capability to Reduce EMI Generation

A High-Voltage Series-Stacked IGBT Switch With Output Pulse Shaping Capability to Reduce EMI Generation

A Novel Local Voltage Sensing Mode for High Voltage IGBT Sensor

Collector-emitter voltage ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ce</sub> ) detection of insulated gate bipolar transistors (IGBTs) is important for safety-critical and mission-critical power applications. The conventional voltage sensing method is characterized by the detection range from 0 V to the rated voltage in the application ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</sub> ), which is limited by the contradiction between the dynamic range of the signal and the ADC resolution in high voltage situations. This letter proposes a novel local voltage sensing (LVS) mode, in which the detection range is from <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">st</sub> to <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</sub> , where <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">st</sub> is a controllable starting point for the sensed voltage. Based on the LVS mode, a novel controllable voltage sensor structure is given, which can provide a sensing signal that is a scaled version of the large <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ce</sub> when <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ce</sub> ≥ <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">st</sub> . <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">st</sub> can be controlled by applying a negative voltage to a control electrode gate ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G2</sub> ). An analytical model is derived to understand the mechanism of the sensor and simplify the design. The effects of internal and external parameters on the sensing characteristics are simulated using Medici & TS4. Furthermore, the sensor is incorporated into a prototype 1200-V IGBT. The test results show that, under the condition of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G2</sub> = 0 V or <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G2</sub> = −1 V, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">st</sub> and nonlinear error are 622 V and 3.9% or 708 V and 3.4%, respectively, and the experimental data agree with the analytical model results. Finally, an application of dc-bus voltage monitoring using the LVS mode is presented.

A Method for Increasing the Bandwidth of Rogowski Coils Without Changing Their Size

According to published papers on Rogowski coils, the sensitivity of Rogowski coils can be increased by using high-density turns and multilayer turns. Low-density turns can increase the bandwidth of the coil but can also reduce the anti-interference ability of the coil. The shielding layer can also increase the anti-interference ability of Rogowski coils. However, for Rogowski coils with high-density turns, using a shielding layer or multilayer turns will reduce their measurement bandwidth. To increase the application flexibility of a Rogowski coil, this article proposes a method capable of increasing the bandwidth without sacrificing size, sensitivity, anti-interference, and measurement accuracy. In this method, coils are segmented without reducing the number of turns, and the induced voltage of the segmented coils is output through the voltage followers and joined together by an adder. Seventeen Rogowski coils are wound by an automatic coil winding machine. These 17 coils consist of single-layer coils, double-layer coils, coils without a shielding layer, and coils with a shielding layer. The method is verified for use with Rogowski coils when measuring the sinusoidal current and the turn-on/off pulse current of an high voltage-insulated gate bipolar transistor (HV-IGBT) collector. The measurement errors of this method and the error compensation method are also explored both theoretically and experimentally.

A Resonant One-Step 325 V to 3.3–10 V DC–DC Converter With Integrated Power Stage Benefiting From High-Voltage Loss-Reduction Techniques

This work presents a self-timed resonant high-voltage (HV) dc–dc converter in HV CMOS silicon-on-insulator (SOI) with a one-step conversion from 100–325 V input down to a 3.3–10 V output, optimized for applications below 500 mW, such as IoT, smart home, and e-mobility. Unlike bulky power modules, the HV converter is fully integrated, including an on-chip power stage, with only one external inductor (10 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{H}$ </tex-math></inline-formula> ) and capacitor (470 nF). It reaches a high power density of 752 mW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> , an overall peak efficiency as high as 81%, and a light-load efficiency of 73.2% at 5 V and 50 mW output. HV loss-reduction techniques are presented and experimentally confirmed to offer an efficiency improvement of more than 32%. Integrated HV insulated gate bipolar transistors (IGBTs) are discussed and implemented as an attractive alternative to conventional integrated HV power switches, resulting in ~20% smaller area at lower losses.

Electric Field Mitigation in High-Voltage High-Power IGBT Modules Using Nonlinear Conductivity Composites

Wide bandgap (WBG) semiconductor devices are developing rapidly due to their superior performance compared to traditional silicon-based devices. However, the packaging technology of traditional devices has limited the application of WBG semiconductor devices because of the challenges in electrical insulation. The complex environment of high blocking voltage, high frequency, and high temperature is the major reason for insulation failure of encapsulation structure. Therefore, in this article, an epoxy resin composite with nonlinear conductivity is proposed to be used as a coating to improve the electric field distribution of high-voltage high-power IGBT modules. First, an electrical field simulation model was built considering the thermal stress. It was found that the electric field in high temperature was improved compared with that in room temperature due to the temperature-dependent conductivity of silicone gel. Nevertheless, the risk of insulation failure still exists. After the application of nonlinear conductivity materials (NCMs) coating, the maximum electric field at the triple junctions and the ratio of electric field distortion in high field areas were significantly decreased. Further analysis showed that the optimization ratio of electric field increased with the increase of the blocking voltages or power losses in the IGBT chip. The results have demonstrated that the NCMs can reduce the maximum electric field in the IGBT encapsulation structure by 73% under the operating conditions of 120 W 10 kV. Partial discharge (PD) tests show that the partial discharge initial voltage (PDIV) of the substrates with NCM coating is increased by 33% compared with the normal encapsulation structure and the coating significantly inhibits the growth of electric trees. The presented results indicate that the NCMs have the potential to improve the insulation performance of high-voltage high-power IGBT modules.

The Impact of Different Operation Conditions on the Plasma Extraction Transit Time Oscillation in High-Voltage Insulated Gate Bipolar Transistor Devices

During the tailing current period when the bipolar device is turned off, plasma extraction transit time (PETT) oscillation will occur, and the electromagnetic interference caused by it will have a negative effect on the driver circuit and the surrounding electronic components. Therefore, it is necessary to investigate the factors that affect the characteristics of PETT oscillation. In this paper, the relationship between the characteristics of PETT oscillation and the operation conditions of high-voltage insulated gate bipolar transistor (IGBT) device is studied experimentally. When the DC link voltage, load current and gate driver resistance are changed, and the peak value and duration of PETT oscillation under different operation conditions are recorded. The results show that the PETT oscillation characteristics have a strong dependence on the voltage and current of IGBT device, as well as the gate driver resistance. The experimental results in this paper can provide the guidance for suppressing the PETT oscillation of high-voltage IGBT devices.

Experimental verification of bidirectional modular multilevel cascaded converter suitable for applying 120‐degree discontinuous pulse width modulation maximum

AbstractModular multilevel cascaded converters (MMCCs) have advantages in the application of high or medium voltage without transformers. They can also generate high‐quality voltage with fewer harmonics. Their unique merits make them leading technology candidates for high/medium voltage applications. However, a concern still exists that the number of parts may be increased. In this study, an MMCC topology using high‐voltage IGBT (HV‐IGBT) with snubber capacitor connected in parallel as a cell module arm is proposed, by which the number of cells can be halved and conduction loss can be significantly reduced owing to the output current flowing through the HV‐IGBT in one‐third of the cycle. Meanwhile, the proposed control stratagem can control the cell capacitor voltage, suppress the HV‐IGHT surge voltage, and avoid short‐circuiting of the snubber capacitor by circulating current. This study reports the evaluation results of capacitors and the experimental results of bidirectional active power conversion operation.

Design new voltage balancing control series connected for HV-IGBT`s

&lt;span&gt;The insulated gate bipolar transistors (IGBTs) are widely used in various applications as they require low gate drive power and gate voltage. This paper proposes an active gain circuit to maintain voltage stability of series-connected IGBTs for high voltage applications. The novel gate driver circuit with closed-loops control amplifies the gate signal while restricting the IGBT emitter voltage below a predetermined level. With the proposed circuit, serial-connected IGBTs can replace high-voltage IGBTs (HV-IGBTs) for high-voltage applications through the active control of the gate signal time delay. Closed-loop controls function is to charged current to the gate to restrict the IGBT emitter voltage to a predetermined level. This paper also presents the experiment on the gate driver capability based on a series-connected IGBTs with three IGBTs and a snubber circuit. The experimental results show a voltage offset with active control with a wide variation in load and imbalance conditions. Lastly, the experimental results are validated with the simulation results, where the simulation results agree with the experimental results.&lt;/span&gt;

The three-level inverter topologies analysis for application by electric centrifugal pump units

In the article, the schemes for providing AC power with frequency conversion for the induction submersible electric drive of oil production units are analyzed. The electric submersible drive is widely used and has stringent efficiency requirements, so this research is relevant. The centrifugal pump units are composed of a low-voltage power source, a frequency converter, a step-up transformer, a cable line, an electric drive and a centrifugal pump. This article discusses options for replacing the step-up transformer and two-level voltage / frequency converter with a three-level flying capacitor converter (FCC) or a three-level clamping diode converter (NPC). The expected states of the power high voltage IGBT modules are described. The waveforms of the inverter output voltage and the submersible induction motor stator voltage in different circuits are shown. A voltage levels analysis for each module is done, the electric drive starting time change is estimated, the total harmonic distortions (THD) are calculated, and a 1.1% THD reduction by applying the NPC circuit is shown. The harmonic current spectrum for each circuit is presented.

An Active Voltage Balance Method Based on Adjusting Driving Signals Time Delay for Series-Connected IGBTs

Connecting low-voltage insulated gate bipolar transistor (IGBT) in series to withstand much higher dc -link voltages has some advantages over using a single high-voltage IGBT or the multilevel topologies. However, severe voltage imbalance during turn-off transient remains to be solved. In all existing methods, adjusting driving signal time delay (ADSTD) is attractive and has no penalty of sacrificing the switching performance of IGBT. Moreover, instead of using a snubber, the voltage imbalance caused by the difference in tail currents can be mitigated by using ADSTD as well. An active voltage balance method based on ADSTD is proposed and verified by experiments in this article. Besides, a more accurate equivalent capacitance for IGBT considering the stored carriers in the n-drift region is discussed. The factors affecting a proper driving signal time delay are also discussed in detail. These contents are well supported by experimental results as well.

Electromagnetic Disturbance Characteristics and Influence Factors of PETT Oscillation in High-Voltage IGBT Devices

Plasma extraction transit time (PETT) oscillation occurs when insulated gate bipolar transistor (IGBT) devices turn off, whose frequency can reach hundreds of MHz. This high-frequency oscillation can induce electromagnetic interference problems and may exceed relevant IEC limits for electromagnetic emission. As one of the electromagnetic disturbance sources from internal IGBT, the PETT oscillation has not attracted much attention in the electromagnetic compatibility (EMC) problems of application and development of high-voltage IGBT devices yet. In this article, the detailed characteristics of PETT oscillation, i.e., oscillation frequency, duration time, and oscillation peak, in high-voltage IGBT devices are systematically investigated by experiments. From the results, oscillation frequency increases with the increase of reverse voltage, whereas decreases with the increase of the temperature. Then, more complex dependencies of the PETT oscillation characteristics on IGBT's commutation conditions are presented. It is shown that its characteristics vary greatly under different reverse voltage, forward current, and temperature. The hazard of PETT oscillation to electronic components is discussed as well. PETT oscillation occurs during the turn-on process, which is first reported. Based on the experiment results, the EMC test related to PETT oscillation is suggested to be performed under different commutation conditions.