1408
B. Feng et al.: Thermal Characteristics of All-Film Pulsed Capacitors in Application of Repetitive Pulse Discharge
Thermal Characteristics of All-Film Pulsed Capacitors
in Application of Repetitive Pulse Discharge
Bingyang Feng, Yuansheng Li and Mengbing He
State Key Laboratory of Advanced Electromagnetic Engineering and Technology
Huazhong University of Science and Technology, Wuhan, China
ABSTRACT
Temperature rise is one of the major causes for all-film pulsed capacitor (AFPC) failure
under high repetitive high-voltage pulse discharge operations. To study the thermal
characteristics, a thermal simulation model is established. In this model, the actual
operation conditions of capacitors are applied. The practical internal structure and heat
production transfer of the AFPC are considered. The validation of the model is proved
by the simulation and the experimental results. Based on the finite element method
(FEM), the overall temperature field distribution of the AFPC, and the mathematical
model between discharge voltage, frequency and temperature rise can be calculated. This
model is capable of evaluating the temperature rise characteristics of an AFPC in
repetitive high-voltage pulse discharge and can provide certain instructive suggestions
for the safe operation and the optimal design of AFPC.
Index Terms — all-film pulsed capacitor (AFPC), repetitive high-voltage pulse
discharge, thermal characteristic, finite element method (FEM), frequency
1 INTRODUCTION
THE development of high repetition rate pulsed power
devices has become an important research direction in pulsed
power technology in recent years [1–3]. High power pulse
capacitor plays an important role in energy storage and
discharge. In order to achieve certain stringent requirements,
including short rise time, high power and high repetitive
frequency, capacitors must be able to reach certain levels of
high voltages, high currents, have low inductance, long
lifetime, and good thermal conductivity. The all-film pulsed
capacitors (AFPC) have the characteristics of small size, light
weight, low loss, low-temperature rise, and excellent partial
discharge performance, so they are widely used in the highvoltage output of pulse sources [4, 5].
The lifetime of the capacitor is one of the key factors
restricting the continuous operation of the pulse power system
[6]. The failure of AFPC is often manifested as a sudden
breakdown, which directly causes the system to stop operating.
Thermal aging is one of the major factors causing breakdown
[7, 8]. In repetitive discharge applications, heat will accumulate
inside the capacitor causing the internal temperature to rise.
The temperature rise will accelerate the aging rate of the
insulating material, which may cause the dielectric material to
decompose and produce certain forms of by-products, such as
gas or carbon particles. These by-products will reduce the
insulation performance and aggravate the aging process of the
Manuscript received on 4 January 2021, in final form 15 May 2021,
accepted 16 June 2021. Corresponding author: M. He.
dielectric. Moreover, if the capacitor exceeds a certain
temperature, it will directly cause thermal breakdown of the
insulating material. Therefore, studying the temperature rise
and distribution characteristics is of great significance to the
optimal design of the capacitor and the maintenance of the
system.
At present, there have already been some numerical studies
on the thermal characteristics of capacitors. Gualous et al [9]
adopted computational fluid dynamics to establish and solve the
temperature field model of supercapacitors. But there is a big
difference between supercapacitors and pulse capacitors, and
the solution procedure was complex. Liu et al [10] assumed the
temperature of the capacitor shell to be a certain value, and
obtained the estimation formula of the highest temperature
between the shell and the interior of the capacitor according to
the heat balance equations. However, the temperature
distribution inside the capacitor was not obtained, and the
formula was inaccurate because of the simplified calculation.
Liang et al [11] established a 3-D finite volume method
temperature calculation model for the power capacitor. The
temperature distribution and the internal maximum temperature
of the power capacitor have been simulated. The validation of
the numerical model was also verified by tests. Nevertheless,
the heat generation of the power capacitor is mainly due to the
dielectric loss, while the pulse capacitor is due to the electrode
heat loss. Li et al [12] investigated the temperature rise of the
metallized film capacitor (MFC) based on the repetition pulse
lifetime test platform. However, the rated voltage of MFC is
relatively low, and there are distinctive differences between
DOI: 10.1109/TDEI.2021.009567
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IEEE Transactions on Dielectrics and Electrical Insulation
Vol. 28, No. 4; August 2021
MFC and AFPC in structure and failure mechanism. Therefore,
the model for MFC cannot be applied in temperature
simulations for AFPC.
This paper takes the AFPC operating under high-voltage
repetitive pulse discharge conditions as the research object,
analyzes the internal structure of the capacitor and the process
of heat generation and transfer, and establishes a simulation
model. The validation of the model has been accomplished by
comparing the simulation and experimental results, which have
shown a good agreement with each other. By using the finite
element method (FEM) to calculate the temperature field,
crucial data have been obtained, such as the temperature field
distribution of the whole capacitor, the temperature rise of both
the internal and the external shell, etc. At the same time,
according to different pulse waveform parameters, the
mathematical model between discharge voltage, frequency and
stationary temperature rise is established. These have certain
guiding significance for the prediction of temperature rise and
safe operation of AFPC under high-voltage repetitive frequency
discharge conditions.
2 CAPACITOR STRUCTURE
AND HEAT TRANSFER PROCESS
2.1 THE STRUCTURE OF AFPC
The target capacitor in this research is composed of core
elements, insulating shell, impregnant, etc. The dielectric
dissipation factor of the capacitor is about 0.0002.
The core element is the most important unit of the capacitor,
which is wound by aluminum foil electrode and dielectric film.
The schematic diagram of the structure is shown in Figure 1.
The dielectric film adopts polypropylene film with low
dissipation factor (~10-4) and high dielectric strength (~600
MV/m at capacitor level) [13], whose structure is simple,
temperature rise is low, and short-term electrical breakdown
performance is excellent. The multilayer film structure is
adopted to avoid the influence of the local electrical weakness
of the film. The aluminum foil electrode adopts a convex foil
structure and a hemming process to improve the electric field
distribution [14].
1409
series-connected cores into the insulating shell, and after
vacuuming, inject the Benzyl Toluene impregnant to complete
the assembly of the capacitor. Table 1 shows the dimension of
the capacitor.
Table 1. Dimension of the capacitor.
Structural parameter
Value
Structural parameter
Value
Shell length (mm)
244
element length (mm)
137
Shell width (mm)
151.4
element width (mm)
90.1
Shell height (mm)
105.1
element height (mm)
17.8
Shell thickness (mm)
6.5
element number
10
2.2 HEAT PRODUCTION AND TRANSFER PROCESS
Understanding the heat generation and transfer process of the
AFPC is the premise of modeling and analysis.
Under high-voltage pulse discharge conditions, the heat is
mainly generated by the pulse current flowing on the aluminum
foil of the capacitor core component, which is conducted from
the inside to the outside; the impregnant near the core transfers
heat to the inner surface of the shell through convection heat
dissipation; the heat from the inner surface of the shell is
transferred to the outer surface through thermal conduction;
finally, all the heat is lost to the air environment by convection
and radiation. The heat transfer process is shown in Figure 2.
Figure 2. The heat transfer process in AFPC.
When the total heating power inside the capacitor is equal to
the total heat dissipation power of the shell, the capacitor
reaches the thermal equilibrium state, and the temperature
distribution of the capacitor remains stable.
3 SIMULATION MODELING
OF THERMAL CHARACTERISTICS
Figure 1. The structure of the AFPC core element.
Several core components are connected in series by soldering
tin and lead-out pieces on the side. Each capacitor component
has an encapsulation gasket to provide insulation. Then put the
3.1 HEAT CALCULATION
The heat of the AFPC in the high-voltage pulse discharge
condition is mainly generated by the large current flowing
through the aluminum foil electrode.
According to [15, 16], the AFPC film structure, shown in
Figure 1, can be divided into n equal infinitesimals along the
film width direction, which is equivalent to a two-dimensional
RC circuit network model, shown in Figure 3a. The Cn is the
capacitance for each infinitesimal film and Rn is the resistance
for each infinitesimal electrode.
Since the current in in each infinitesimal is almost equal,
according to Kirchhoff’s Current Law, the current is distributed
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1410
B. Feng et al.: Thermal Characteristics of All-Film Pulsed Capacitors in Application of Repetitive Pulse Discharge
linearly in the electrodes, shown in Figure 3b, where the x-axis
is the direction in which current flows from the lead-out end of
the electrode convex foil to the clear margin of the dielectric
film [17]. So, the current i(t) is at the maximum value near the
lead-out end of the electrode and at the minimum about zero
near the clear margin. The heat under the action of a pulse
discharge can be calculated as:
2
 b x
i(t )
RAl (t )  dtdx


0 0
b 

Q
t
b
(1)
where b is the effective width between electrode and dielectric
film, as shown in Figure 3b, t is the pulse current action time,
i(t) is the amplitude of the pulse current flowing through the
electrode terminal, and RAl(t) is the varying resistance of the
aluminum foil electrode due to the temperature variation during
discharge.
The convection heat transfer process of the impregnant is
more complicated and needs to meet the conservation of mass,
momentum, and energy. Certain simplifications are made in the
analysis, and the partial differential equation of convection heat
transfer is obtained as:
T
T
T
T
  2T  2T  2T
+u +
+w =
+
(
+
) (3)
t
x
y
z CP x2 y 2 z 2
where u, ν, and w are the velocity of the fluid in x, y, and z
directions, respectively.
When the capacitor temperature reaches a stable value, the
heat transferred to the shell must be balanced with the heat
dissipation of the case through radiation and convection.
Therefore, the surface heat dissipation is used as the boundary
condition on the shell when calculating the coupled field:

(b)
Figure 3. (a) Equivalent RC circuit network model and (b) linear distribution
of current in aluminum foil electrode.
3.2 FLUID-SOLID-THERMAL COUPLING FIELD
There are solid and liquid materials inside the capacitor,
so the temperature model is the calculation of the fluid-solidthermal coupling field. The FEM has become one of the most
popular methods for calculating fluid-solid-thermal coupling
field due to its high accuracy, multiple numerical algorithms,
and multi-grid support [18].
The temperature distribution of the fluid-solid-thermal
coupling field should satisfy the corresponding governing
equations. The forms of heat transfer in the capacitor include
the conduction and convection of the internal medium and the
radiation and convection of the shell and the air.
The partial differential equation of heat conduction in the
Cartesian coordinate system is:
T
 2T  2T  2T
=div( gradT )+   ( 2  2  2 )  
t
x
y
z
=hext (Text  T )   (Text 4  T 4 )
(4)

where Γ is the capacitor shell, Text is the temperature of the
environment, T is the temperature of the shell, hext is the heat
dissipation coefficient of the shell, n is the unit vector of the
outer normal direction on the shell, σ is the Stefan-Boltzmann
Constant, σ = 5.67 × 10-8W/(m2ꞏK4), and ε is the radiation
coefficient of the shell. Because the value of σ is small, it can
usually be ignored.
(a)
 CP
T
n
3.3 SIMULATION MODEL ESTABLISHMENT
For the convenience of modeling and calculation, the core
element made of polypropylene film, aluminum foil and Benzyl
Toluene impregnant are equivalent to a whole. Calculate the
equivalent density and specific heat according to the thickness
of aluminum foil, polypropylene film, and Benzyl Toluene
 d Al  Al  d PP  PP  d BT  BT
 =
d Al  d PP  d BT


C = d Al  Al CAl  d PP  PPCPP  d BT  BT CBT

d Al  Al  d PP  PP  d BT  BT
(5)
where ρ is the equivalent density and C is the equivalent
specific heat, ρA1, ρPP, ρBT are the densities of aluminum foil,
polypropylene film, and Benzyl Toluene impregnant,
respectively, and CA1, CPP, CBT are the specific heats of them,
respectively. The dAl, dPP, dBT are the thicknesses of the media
with the value of 10 μm, 32 μm, and 1 μm.
The equivalent thermal conductivity of the element shows
the anisotropic nature [19], as shown in Figure 4.
(2)
where ρ, CP, and T are the density, specific heat capacity, and
temperature of the micro-element, respectively, t is the time,
λ is the thermal conductivity, and Φ is the heat power per unit
volume. In this model, the core elements are set as the heat
source.
Figure 4. Anisotropy of element heat conduction.
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IEEE Transactions on Dielectrics and Electrical Insulation
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1411
In x and y directions, the internal heat conduction of the
element is parallel, which means the multi-layer dielectric
conducts heat at the same time. In z-direction, the internal heat
conduction is in series, which means the multi-layer dielectric
conducts heat sequentially. So, the thermal conductivity in
different directions can be described as:
d Al Al  d PP PP  d BT BT

x =y =
d Al  d PP  d BT


d Al  d PP  d BT
 =
 z d Al Al  d PP PP  d BT BT
where λA1, λPP, and λBT are the thermal conductivities of
aluminum foil, polypropylene film, and Benzyl Toluene
impregnant, respectively.
Table 2 shows the property parameters of various materials in
the capacitor. According to the above analysis and the parameters
in Table 1 and Table 2, a simulation model is established in the
FEM software. Mesh division is the key to FEM. The quality of
the mesh is directly related to the simulation time and the
accuracy of the simulation results, so finer mesh division is used
to ensure the quality. The overall model of the AFPC and the
mesh division result are shown in Figure 5.
Table 2. Material property parameters.
Material
Specific heat
(J/(gꞏ°C))
Density
(g/cm3)
Aluminum foil
Polypropylene film
Benzyl toluene
Insulated shell
0.89
1.9
1.6
2.3
2.7
0.89–0.91
0.98
0.84
(a)
(6)
Thermal
conductivity
(W/mꞏK)
238
0.22
0.12
0.33
(b)
Figure 6. Determination of heat dissipation coefficient: (a) the AFPC
prototype heated in the chamber with a constant temperature and (b) comparison
of experimental surface temperature and simulation in the cooling process.
The results indicate that the experimental data matches well
with the simulation, which has a heat dissipation coefficient of
7.5 W/(m2·K). Therefore, the heat dissipation coefficient of
the capacitor shell is chosen as 7.5 w/(m2·K). This parameter
contains the heat loss caused by convection and radiation.
4
RESULTS AND DISCUSSION
4.1 COMPARISON OF SIMULATION
AND EXPERIMENTAL RESULTS
The repetitive frequency high-voltage pulse discharge
platform is shown in Figure 7. Adopting the burst repetition
frequency mode, the primary energy storage capacitor is
charged by the high-voltage charging power supply. The
discharge of the primary capacitor is controlled by the thyristor
in parallel with the reverse diode, and the energy is transferred
to the AFPC in the form of the pulse transformer. Through the
switch-on of the self-trigger gap, the AFPC discharges to the
load.
Figure 5. Capacitor simulation model and mesh division.
3.4 DETERMINATION
OF HEAT DISSIPATION COEFFICIENT
To obtain the heat dissipation coefficient of the capacitor
shell surface, the AFPC prototype is placed in a thermostat with
constant temperature and heated, as shown in Figure 6a, then
placed in air for cooling while recording the surface
temperature in the center of the surface.
Meanwhile, three heat dissipation simulations with different
heat dissipation coefficients are set, and the heat dissipation
curves obtained by the simulation are compared with the actual
data. The results are shown in Figure 6b.
Figure 7. High voltage repetitive frequency pulse discharge platform.
Based on the experimental platform, the repetitive discharge
experiment was conducted on the AFPC at the discharge
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B. Feng et al.: Thermal Characteristics of All-Film Pulsed Capacitors in Application of Repetitive Pulse Discharge
voltage of 30 kV. 5 identical capacitors of the same
manufacture batch are adopted and operating under the same
experimental conditions. Through the measurement of the
oscilloscope, the typical voltage and current waveforms of a
single discharge are shown in Figure 8. Under the repetitive
pulse discharge conditions, the pulse platform discharges 5
times per second, which means the frequency is 5 Hz. Each
discharge time is 5 μs, and the cooling time is about 0.2 s.
Figure 10. The AFPC surface temperature rise result of simulation and
experiment.
is appropriate to use this model to simulate and predict the
thermal characteristics of the AFPC in actual conditions.
Figure 8. Typical voltage and current waveform of HV pulse discharge.
The temperature data of the different external surfaces
measured by the Fluke TiS60+ Thermal Imager are shown in
Figure 9. At the same time, according to the typical discharge
waveform, shown in Figure 8, the transient temperature rise
calculation is performed in the model at the same condition.
According to Equation (1), the heat of a single pulse is 2.3662
J calculated by MATLAB. By the calculation and comparison
of the energy at different times, the heat generated on the
aluminum foil electrode at each discharge is turned out to be
approximately uniform, and the electrode in the experimental
condition can be considered as a stable heat source. The
temperature of the environment in the simulation is set to 23 ℃,
which is consistent with the experimental environment. The
results of the experiment and simulation are compared in Figure
10. It can be seen that the curves fit well, which means that it
4.2 THE TEMPERATURE
DISTRIBUTION OF THE AFPC
Considering that in actual application, the high-voltage
repetitive pulse discharge platform needs to run continuously,
the duration of repetitive pulse discharge operation is set to
600 min in the simulation model. After the simulation is
completed, the temperature field distribution diagrams of AFPC
at different times are shown in Figure 11. It can be seen that the
distribution of the temperature field is not uniform, and there
are partial hottest points.
Figure 11. Temperature field distribution of AFPC at different times.
(a)
(b)
(c)
(d)
Figure 9. The temperature of the different external surfaces: (a) the front
surface, t = 30 min, (b) the front surface, t = 110 min, (c) the side surface,
t = 50 min and (d) the side surface, t = 110 min.
By using a probe to measure the temperature of the hottest
point inside the capacitor and three different external surfaces,
the temperature rise curves obtained are shown in Figure 12.
When the repetitive pulse discharge duration is about 600
minutes, the curves tend to be flat, indicating that the heat
production and dissipation of the capacitor are basically in
balance. The maximum temperature of the capacitor is inside
the element, which indicates the temperature of the dielectric.
It is 11.24 ℃ higher than the front surface, 16.52 ℃ higher
than the side surface, and 18.21 ℃ higher than the top surface.
The difference in surface temperature is mainly due to the
structure of the core elements and the anisotropy of thermal
conductivity.
According to the Law of Arrhenius, the high temperature will
deteriorate the performance of the dielectric material. It has
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1413
(a)
Figure 12. Temperature rise curves at different locations.
been indicated that the breakdown strength of the dielectric film
is independent of temperature up to 40 °C and drops linearly as
a function of temperature by almost 10% between 40 °C and
80 °C due to the enhanced thermal aging mechanism [20, 21].
Therefore, the maximum allowable temperature of the internal
dielectric medium of AFPC is usually 80 °C. Taking the
temperature of the dielectric as the evaluation object, the
temperature tends to stabilize after 600 minutes, as shown in
Figure 12, and the maximum temperature of the dielectric is less
than 80 ℃, indicating that the capacitor can operate safely for
a long time under this condition.
4.3 THE MATHEMATICAL MODEL
BETWEEN DISCHARGE VOLTAGE,
FREQUENCY, AND TEMPERATURE RISE
In the application of repetitive pulse discharge, voltage and
frequency are indicators that need lots of attention. Therefore,
to study the effect of voltage and frequency on temperature rise,
calculations at different frequencies and different discharge
voltages are set to obtain the highest temperature rise curve, as
shown in Figure 13.
It can be seen in Figure 13a that the temperature rise of the
capacitor is very small and basically remains constant at 1 Hz.
At 5 Hz and 10 Hz, the capacitor can operate continuously and
stably for a long time. But at 15 Hz, after about 212 min, the
highest temperature of dielectric exceeds 80 ℃. Also, as shown
in Figure 13b, the capacitor can operate continuously and stably
at 15 kV, 30 kV, and 45 kV. But at 60 kV, after about 128 min,
the highest temperature exceeds 80 ℃. In this state, the
probability of thermal aging of the dielectric medium and
internal breakdown of the capacitor is greatly increased, which
is very likely to cause the sudden failure of the capacitor and
affect the continuous operation ability of the discharge
platform.
Based on the stationary temperature of the hottest spot of
the dielectric inside capacitor, the relationship between the
highest temperature rise and frequency at different voltages,
and the relationship between the highest temperature rise and
voltage at different frequencies are obtained, as shown in
Figure 14.
(b)
Figure 13. (a) The highest temperature rise curves at different frequencies and
(b) the highest temperature rise curves at different voltages.
Through the method of fitting analysis, the regression
equations between stationary highest temperature rise,
discharge voltage, and frequency are obtained as:
Tmax =Text  k f  U 2.0068

0.9979
Tmax =Text  kU  f
(7)
where Tmax is the highest temperature of the dielectric inside the
capacitor, Text is the temperature of the environment, U is the
amplitude of the pulse voltage in kV, f is the discharge
frequency in Hz, kf is the model coefficient related to the
capacitor model, and frequency, and kU is the model coefficient
related to the capacitor model and voltage.
From Equation (7), there are reasons to believe that within an
appropriate range, there is a mathematical relationship between
stationary highest temperature rise, voltage, and frequency. So,
after enough calculations, the surface model of the relationship
between them is obtained, as shown in Figure 15.
Through the method of nonlinear surface fitting analysis, the
mathematical model between stationary temperature rise,
discharge voltage, and frequency can be summarized as:
T m a x  T ext  A  f
0 .9 9 7 9
U
2 .0 0 6 8
 B f
0 .9 9 7 9
C
(8)
where A is the model coefficient, which is 0.00557, B is the
model coefficient, which is 0.00571 with a root mean squared
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B. Feng et al.: Thermal Characteristics of All-Film Pulsed Capacitors in Application of Repetitive Pulse Discharge
(a)
(b)
Figure 14. (a) The relationship between the stationary highest temperature rise
and voltage at different frequencies and (b) the relationship between the
stationary highest temperature and frequency at different voltages.
Figure 15. The surface model between discharge voltage, frequency, and
stationary highest temperature rise.
error of 0.00716, and C is the model coefficient, which is
0.0218 with a root mean squared error of 0.04718.
4.4 DISCUSSION
It can be found that the thermal field distribution of the AFPC
is not uniform, and there are partial high temperatures appear
during repetitive pulse operations. The highest temperature
showed up inside the capacitor, which indicated the maximum
temperature of the dielectric. The temperature on each surface
was different due to the structure of the core and the anisotropy
of thermal conductivity. The model based on Equation (8)
indicates that there is a mathematical relationship between
stationary temperature rise, discharge voltage, and frequency.
Since the measurement of dielectric temperature inside the
capacitor is usually not convenient, by using such the
simulation and mathematical model, the stationary temperature
of the whole AFPC under the practical application of repetitive
pulse discharge can be calculated and predicted before the
operation, and the security state of the system can be guaranteed
within an appropriate range of voltage and frequency.
Therefore, considering from improving the thermal
characteristics and reducing the maximum temperature rise of
dielectric inside the AFPC in the application of repetitive pulse
discharge, the capacitor can be installed vertically or
horizontally to obtain a larger heat dissipation area. At high
voltages and frequencies, it is necessary to install cooling
equipment in the repetitive pulse power system because there
will be an unacceptable temperature rise after a period of
continuous operation. Besides, the structure of the AFPC needs
to be optimized. For example, adopting insulating shell
materials with high heat dissipation performance can ensure
that the capacitor transfers enough heat to the external
environment during the pause of discharge, and the highfluidity impregnant can ensure the internal thermal field
distribution of the capacitor relatively uniform.
5 CONCLUSIONS
This paper focuses on the thermal characteristics of the
AFPC at the high-voltage output of the pulse source in the
application of high-voltage repetitive pulse discharge, analyzes
the internal structure of the AFPC and the heat production and
transfer process. The temperature rise analysis model is
established and validated by comparison with experiments, and
the temperature rise of AFPC under different discharge
frequencies and pulse voltages are obtained based on the FEM
method.
The results show that the internal temperature rise of
dielectric inside the capacitor is the highest after a period of
operation. The temperature distribution of each surface of the
capacitor is different, while the top and side surfaces are lower.
Therefore, the capacitor can be installed vertically or
horizontally. The mathematical model of the relationship
between temperature, frequency, and voltage is obtained by the
fitting method. This model can be used to calculate and predict
the temperature rise of the AFPC under different conditions to
ensure safe operation. At high voltages and frequencies, the
temperature rise of the capacitor is higher and the heat
generation is faster. It is necessary to add additional heat
dissipation equipment or improve the structure and thermal
characteristics of the AFPC, such as the adoption of insulating
shell materials with high heat dissipation performance and
impregnant with high fluidity.
In order to make the simulation model more consistent with
the actual application, the temperature distribution of the
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IEEE Transactions on Dielectrics and Electrical Insulation
Vol. 28, No. 4; August 2021
surrounding environmental airflow field can be taken into
consideration in the next step.
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Bingyang Feng was born in China. He received his B.Eng.
degree in electrical engineering and automation from
Huazhong University of Science and Technology, Wuhan,
China, in 2017. Currently, he is working toward a Ph.D.
degree in electrical engineering at Huazhong University of
Science and Technology, Wuhan, China. His research
interests include design and analysis of high-voltage and
high-power pulse source, and high-frequency and highvoltage conversion technology.
Yuansheng Li was born in China. He received his M.Eng.
degree in electrical engineering from Huazhong
University of Science and Technology, Wuhan, China, in
2018. Currently, he is working toward a Ph.D. degree in
electrical engineering at Huazhong University of Science
and Technology, Wuhan, China. His research interests
include gas switch, high power pulse source and high
voltage pulse discharge crushing technology.
Mengbing He was born in China. He received his M.Sc.
degree from Wuhan University, Wuhan, China, in 1998,
and a Ph.D. degree from Huazhong University of Science
and Technology, Wuhan, China, in 2003. Currently, he is
a professor at Huazhong University of Science and
Technology. His research interests are gas switch and high
voltage capacitor for pulse power technology, high power
pulse source, pulse electric dust removal technology, high
voltage pulse discharge crushing technology and application of solid-state
switch in pulse power technology.
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