Science topic
High Voltage Engineering - Science topic
High Voltage Engineering are it is a special application field of Electrical Engineering, specially becoming more popular and demanding due to Power Transmissions at Ultra High Voltage level.
Questions related to High Voltage Engineering
Following the success of ISH2023 at the University of Strathclyde, Glasgow, I am pleased to share with everyone that the papers have now been published in the IET Proceedings. The next Symposium (ISH2025) will be in Tokyo and I look forward to welcoming all of you there.
However, we wish to increase participation by more researchers in the area of High Voltage Engineering. Any suggestions please?
I want to explore the following topic :
Is it possible to simulate the phenomenon of Water Treeing in COMSOL ?
Water Treeing is the phenomenon of partial breakdown of the Dielectric Medium in an Insulator Material between two electrodes (or conductors) due to a group of factors (like presence of humidity, contamination, or impurities).
What I want to know is; whether someone has done this before, or someone know about reports or articles where these "Trees" have been simulated? In practice, these phenomena are interested tipycally for polymers like; Polyethylene, Polypropylene, other Eleastometers, etc.
I would like to perform a simulation of one of this Water Trees ocurring inside an insulator materal in a power transmission cable operating on standar condicionts under Medium Voltage.
I would like to predict the pattern and the direction of the path taken by the breackdown, the size and shape of the "Tree" and the duration from the initial point 'till the time when the breackdown reach the other conductor.
Hope someone knows more about this
Best Regards !:)
why dc capacitor charge faster than it discharges? Can we control charging and discharging time?
I have a power supply which is consists of a flyback and a circuit.
It is a dual output power supply that have 3 wires in output(a. ground wire, b. 4kv, c. 8kv).
in put voltage is 220v and the power of this power supply is 50 watts.
I need to simulate this power supply in ltspice or any similar software so I need to know the specs of the flyback transformer.
how can I find the specs of this transformer without destroying it? :D


I compensate my series resistance 75-80%, I have sodium currents that range from 0.5 to 6 nA, and my pipettes are 1.5-3 megaohms.
Are there any models to predict when an "Electrical Tree" or a "Water Tree" will occur inside an electrical insulator (dielectric materials as Polyethylene, Polypropylene, etc.) working on its normal operating conditions for Medium Voltage or High Voltage applications ? i.e. the Electric Insulator material covering the conductor cable in underground power cables (MV and HV)
Are there any theoretical or empirical models to predict these phenomena ? When treeing will occur along the life of an electrical power cable?
Regards !
I’m using COMSOL for circuit breaker PSS-1 2D time-dependent simulation. I have coupled all moduls: Heat Transfer in Fluids, CFD-Modul, Electric Currents, Magnetic Fields, Moving Mesh
in HT-Modul I use 3 HeatSources for Simulation of radiation, Joule-Heat(ec volumetric los), enthalpy transport.
in CFD Modul I use Force for Lorenz-Force consideration
EC and MF moduls are coupled with external current density.
MF:full field, ”in plane“ field, gauge A-fixing
boundary conditions: walls
initial values: T=293K, P=1atm(with hydrostatic correction), DC terminal 100A and ground.
between electrodes T=10000K or I tryed to use Gauss-Pulse function (quasi same effect)
Solver: fully coupled
Method: High-nonlinear Newton
Goal: to simulate plasma in switching device correct and watch internal thermo-hydrodynamics and V-A characteristics of circuit breaker.
when I start to calculate my modell, I receive no convergence in both Stationary and Time-Dependent cases.
when somebody need a comsol-file, just ask it
Can someone suggest me the latest, novel and most ongoing active research activities and research topics in Electrostatic Precipitation and High Voltage Power Supply Design?
Especially for the non-condenser bushing. I'm studying FEM analysis.
In High Voltage Engineering by Naidu & Kamaraju(3rd edition) the following is seen in Chapter 3, Conduction and breakdown in Liquid Dieletrics,
Section 3.4.5 Conclusions:
Vb=Adn
Where: d=gap length, A= a constant, and n= a constant, n<1
Now, what is the electric field?
Is it E=Vb/d = (Adn)/d
OR
Is it E= dV/dd = (nA dn-1)
As you can see the answers will be very different!!
ERB
I need some theoretical literature on ferroresonance choke and high voltage choke.
as you know for making the phases of transmission lines symmetric we transpose the lines,i want the suitable Distancefor transposing
My Requirement is to create an equation to calculate the distribution line power loss with distance and solve it to get an optimum distance. all other variables can be predefined within the equation, (i.e. voltage drop of cable, cable resistance, tem, X axis distances to side roads, Y axis distances from loads,) - finally calculate X* Figure attached will clarify the X, Y-axis and Rectangles indicate loads. Circled X is the power source (Battery Bank with 3-phase inverter) Note - Distribution system is a 3-phase line system, cable parameters are known (50mm or 70mm ABS), Ignore street light conductor in cable parameters, for the equation , pls consider on its capability of calculating loads up to 10 homes in a lane and 10 lanes (needs at least 100 homes for this system) this equation can be solved using any software means necessary, thus not focusing on that, will you be able to provide me the equation within 2 days


Since the wind turbine has a tall structure, it is more affected by lightning than others. We can distinguish several paths of lightning current to the wind turbine generator and to protect these systems might be the redirection of the discharge current into the earth through the grounding system is the solution. Even without the possibility of being struck by lightning, wind turbines contain sensitive electronic equipment. Is the electromagnetic field (E and B) generated during the current flow (in the down-conductor) can cause damage? if yes, how to solve this problem?
I think there are two methods are available to improve HVDC circuit breaker which means make the dc current artificially zero.
They are 1)LC oscillation method
2)Add external voltage source method
If you know any methods other than above two then give me your answers.
Some experts told that HVDC is better transmission system.
HVDC eliminates the problems of AC system as well as economical benefits.
On the other hand, the initial cost of the LFAC (low frequency AC Transmission) system is lower than HVDC system.
Which formulas can help me calculate the maximum distance of HVAC submarine cables?
By how much does shunt compensation increase maximum distance of HVAC cable?
I am doing high frequency modelling of the substation equipments for lightning studies. please help me to model VSC valve in detail.In addition to this help in grounding part also..
I'm trying to measure the leakage current along an insulator energize with HVDC (the effect of space charges is been considered).
- Can I connect a picoammeter to the ground electrode? If yes, please how do I protect the picoammeter so as not to damage it?
Or
- Can I connect a voltage divider (with 5kohms and 50ohms connected in series) at the ground electrode, measure the voltage across the 50ohms with a picoscope and from there I can use V=IR to get my current? If yes, please how do I protect the picoscope from getting damaged?
Thanks.
How to protect the electrical installations in the aircraft in case of lack of ferroresonance or other similar? (fault currents of high-frequency)
Caught in the vicinity of metro lines high currents, causing severe corrosion in oil and gas installations Here are tips to solve the problem. thank you
Mathematical analysis of current waveform
I have research about inductance of toroidal transformer, On my research, i'am using magnetostatic when the model are given steady current (or DC), then i got question from my friend, because we know that transformer are device that working with AC current, do you think that is worth if we do simulation with DC current to the toroidal transformer, if you want to know more about transformer? or i just change the current to AC?
In of calculation or analysis of pre breakdown of insulation related article.
During bad weather and pollution atmosphere how I can measure electromagnetic interference between them.
Hi,
I am designing a water cooling system for high power IGBTs, but I don't know how to do that, such as selecting heat sink, velocity of water etc.
If I have known the losses of IGBTs, thermal impedance of IGBTs, ambient temperature, how to design a proper water cooling system.
Best regards,
Yi
Rework activities are done by manufactures in order to get good results at partial discharge test.
I am wondering if there is any potential damage/fault can be caused by low-frequency electrical resonance within a power grid or system due to internal or external inductive and capacitive components.
If this is possible, what would be some good examples to prove this point?
Thanks so much!
Hi all
Is there any expressions or explanation of corona effects in high-frequency ?
I need theorical or experimental works.
Thank you,
Omar
It's well known that in high voltage transformers, the contents of harmonics in the applied voltage are induced by the non-linear behavior in the saturated part of the magnetizing curve of the testing transformer core. In addition, non-sinusoidal magnetization current causes a distortion of the secondary voltage. Is there any solution in order to improve the applied voltage signal and decrease its harmonic components ?
I'm obtaining the thickness of insulation in shielded power cables and I find as a reference a standard Japanese (JEC-3408 - High voltage tests for extra high voltage cross-linked polyethylene cables and connection parts) but i would like to know, the equivalent standard in the IEEE or IEC.
Do somebody know the equivalent standard in the IEEE or IEC ?
hi.The high-voltage transmission lines, in some places, high balls or Yayyn be installed in Dersim. what is the reason?
We know for Bose-Hubbard model in simple lattice, the ground state could be Mott insulator with integer number of particles per site and it is a commensurate phase. When the lattice is a superlattice, there appears fractional-filling Mott insulators with rational number of particles per site. I want to know is the fractional-filling Mott insulator is also commensurate.
I think this method is used for measuring partial discharges. Please share relevant material for the same. Thank you.
I have found that distribution transformer failure differs from altitude to altitude. One of the main reason being frequent lightning in some locations. Therefore, there is a need for different lightning arrester for different locations of transformer.
We are facing a line tripping problem in the 132 kV single source transmission line. The fault is temporary. As we restore the line again after 15-20 minutes the fault does not exist and line works well.
As the fault occur protection relay (earth fault and short circuit fault) operate at sending and receiving end. The fault current at the sending end and receiving end are in 5 kilo ampere (kA) range and 100 mili ampere (mA) respectively.
1. Expecting the complete internal architecture of current transformer rated at EHV level.
2. Site tests & Lab tests conducted on current transformer
I was searching for co-axial/tri-axial cables for our test facility which can carry a current of 60A at voltages ~55kV DC (which are supposed to be modulated at 5kHz continuously).
I observed that the typical co-axial/tri-axial cables are rated like this:
"45kV Pulse or AC and 150kV DC"
I didn't understood what is deciding factor by which we de-rate an dielectric for a AC and DC application.
--
Thanks
When doing analyses with ambient plasma sources (e.g., DART, LTP), there is typically a high background due to junk in the air getting ionized (such as vacuum oil, plasticizers, detergents, etc). Has anyone found a good way to reduce that background signal? It can interfere significantly with any analysis you do.
See these sentences in one technical report: "Reconnection of these inductive loads with an out–of–phase residual voltage present of more than .25 per unit can result in transient currents high enough to trip overcurrent devices and/or transient torque high enough to damage the load equipment".
The goal is to make the initial study for HVDC link back to back , want to do the basic design of the station Back to Back , to model and simulate
I want this study as a reference to plan the station and its final design study
Suppose there is a logic gate and it has two inputs.I want both the inputs to be "high" i.e logic 1, can i have two different voltage values at these two inputs? e.g 3v on one and 4v on another?
Corona current is usually calculated from Ic=sigma*Electric field = ion mobility*space charge*Electric field. In Maxwell, E is available, mobility is constant, the problem in finding the value of space charge density. My application is: electrostatic precipitator (wire-cylindrical or wire-duct).
Can we say connect a single phase customer(instead of all, just a few customers in a LV Distribution network) to all 3 phases but use some sort of relay to select one at any time and then switch the customer at the customer's end to a different phase to control Voltage Unbalance?
Can we preset for certain times?
And if yes then what sort of problems we would face when switching phase? will there be a short time interval where the customer's appliances will be out of power or can we neglect that time? Or may be it is a slow transition?
i want to run avalanche transistor
but i can bias this transistor for this section
please help me to run it
best regard
I want to study the dynamic behavior of a complex power system, including some HVDC links. In which simulation software can I study this?
In order to avoid selection of oversized distribution transformers, it is required to optimize its selection based on their chargeability.
I am currently using fiber optic in my system and need to know the standard leakage current in order to calibrate the system.
There are some inventions made in between 2000 and 2010 about sensing and measuring electrostatic fields. Mainly they deal with solid states (semiconductors) or MEMS Technology (to implement so called field mills). I look for a miniaturized sensor for fields between 1kV/m and 1000 kV/m. Does anybody know products on the market in size of a Computer chip or would somebody be interested in a cooperation to develop a sensor?
We know that high voltage engineering is a very traditional subject. Judging from the present condition, it seems that American universities seldom conduct researches on this area now. However, in Europe and Japan, there are still many researchers in this area. Maybe it is because some large companies like ABB, SIEMENS, ALSTOM, and TOSHIBA, etc. have the motivation to make products with higher voltage level and larger capacity and all theses companies are in the mentioned regions. My question is, are there any institutes, especially universities, doing research related with high voltage or electrical insulation in the USA?
Hello.
Please see the attached images which shows our capacitively gas discharge circuit. HV box has single output of 30 kV.
Before thyratron (fast electrical switch) is on, everything looks clear and no need to worry. But after thyratron is on, among 30 kV or 0, which voltage is right on the HV box side? Although this circuit have works so far. I've always confused this.
I guess the best scenario is the HV side becomes 0 zero and I've believed this way but...why and how?
If this circuit is bad, how can HV side be automatically cut when thyratron is on so the box is protected from , for example, huge current drawing from the box to ground by electrical short?


Hi, everyone
I am wondering where I can find the complete data of IEEE 39bus system, especially the base voltage of both sides of the transformer(since 345KV is only provided for the high-voltage side). Thanks
Hello.
Let's say we have narrow sapphire tube (~300 um width and few cm length) which is filled with gas and discharged capacitively with high voltage of ~ 30 kV. With sub atm pressure, we can get order of 10^18 cm^(-3) plasma density and plasma temperature (both electron and ion are in equilibrium due to such a high density) is about 1~2 eV. This is actually for plasma waveguide for intense laser.
I've always worrying melt down of dielectric material due to direct contact of plasma although it have been reported as successful waveguide.
Is it possible that temperature is significantly reduced within very thin sheath possibly formed in proximity to the dielectric wall? Is it possible that temperature there can be even lower than material melting point?
Please give me any comments on this.
The condition for the occurrence of partial discharge (PD) is commonly associated to the increase of the local electric field up to exceed a critical value. In general, nothing is mentioned about the availability of electric charges as complementary condition for PD occurrence. Rigorously speaking, is it not necessary also to consider the need of free local electric charges as additional condition for PD occurrence?
Complementary to the question, I would like to pose a situation where a cavity is located deep inside a solid insulating body far from electrodes in a high voltage equipment. Such situation I had in mind when I thought about this question. It is a condition where a relative small volume of gas is confined with very low or none availability of electric charges, but with great possibility of being stressed by high local electric field. Should we worry about PD in such case?
Hello all,
I am working with the Pulse Discrimination in micro-EDM (RC Circuit). Their is a very general concept of a class of contributing and non-contributing pulses which are being discriminating on the basis of the charging and discharging location of capacitor. I would like to know the exact theory behind deciding the threshold for such contributing and non-contributing pulses in details. If possible, refer me some publications as i am unable to find it out from my end. Thank You
Dear all,
through litterature, two options exist :
- with SiO2 thin layer : provides a current barrier that can spread space charge region and thus yields higher breakdown voltage
- without SiO2 thin layer : to avoid instability caused by space charge region spreading that may be difficult to control
In case we need SiO2, how can we control it (Piranha clean, low temperature oxidation ...) ?
In case we do not need SiO2, how can we get rid of native oxide ? And I've also read that SIPOS annealing forms a very thin layer SiO2 at the interface so it may be dificult to completely avoid it.
What is your feeling about that ?
Thanks for help !
I work in HVDC systems ,its converters needs transformer in each side of HVDC link ,this transformer must be performed by a tap changer control, i need to know, what is the purpose of this tap changer and the difference than transformer turns ratio.
thanks in advance
When we pass the current through coil heat generated is calculated by Current^2*Resistance*time.So heat generated in coil depends on current,resistance and time. Like, on which factors heat generated due to spark gap depends??
how should load be connected directly with 3-Phase AC high voltage generator that has no neutral wire? Should three loads be connected; something like L1 - L2 , L2 -L3 , L3 -L1 !
Moreover , there is voltage between all three phases. if the voltage is measured only between L1-L2 i.e 100v , is that the actual voltage output of the generator? . Should the voltage is to be read as L1-L2 +L2-L3 =>100V+100V= 200V?
What is the reason for producing high voltage by the ballast(choke) and what is the ballast actually made of?
in transmission line reflected current and voltage is produced whenever there is a short or open circuit condition . i want to know that physical significance of that thing how it has come ? it is induced voltage or anything else how can current flow in both directions means incident and reflected current.
I am trying to find out the maximum ramp rate (practically feasible) for the power reversal operation in a VSC-HVDC system.
Dear researchers,
Experimental investigations are to be carried out on a prototype to determine the design stress levels.
Prototype : Chamber filled with SF6 gas. Conductor running longitudinally and isolated from the tank/chamber by the gas.
Objective: Determine the withstand voltage level with 50% probability through experimentation and establish the 90% withstand voltage level theoretically.
Reason : In up-down method of stressing the insulation, only 1 shot per group is to be applied and there is no mention in the IEC 60060-1 to determine the 90% withstand voltage level.
We know that the breakdown characteristics of SF6 follows weibull distribution. Could I determine the 50% withstand voltage level and extrapolate through curve fitting to obtain 90% withstand voltage level?
If yes, how do I proceed after establishing 50% withstand voltage level? How to determine the maximum likelihood estimator and how is it helpful in this regard?
Thank you
Using ONAF (oil natural air force) cooling conditions, calculate the H. V(high voltage) and L.V(low voltage) side current of the power transformer having following ratings; 31.5/40 MVA, 132/11.5kV ?
What is the minimum and maximum voltage that it could be? Please respond with a valid source. Thank you.
I would like a to build a low cost HV DC power supply.
Specifications would be 3-7KV, low amperage (maybe 2mA at best).
I have seen many examples from old CRT televisions/monitors.
The purpose would be for electrospraying. Fluctuations in power supply are okay, I know that instabilities will occur within the electrospray regime
Does anyone have experience?
I am using electronica leader-1 znc.
I am working on insulation condition monitoring of low voltage network. I would like to know if there is any method or technique for instantaneous detection of insulation fault or leakage current in low voltage network offline. I can not use high voltage as it may harm the insulation of the network.
We would like to know if there are some standardized overloads authorized by TSOs if, for example, any failure takes place in other lines. In addition to this, we would like to know if there is any lifetime reduction assessment available for the power cables under these circumstances.
Since recovery time of a spark gap can be useful in high power pulse applications.
A part of my thesis is to examine different fault events in MVDC architectures for shipboard power systems. A recent thought was to include a fault caused by a lightning strike in order to observe the behavior of my grid and circuit breaker. I found the circuit of the lightning impulse that has been introduced in the literature but I cannot find out how to simulate the sphere gap.
We are aware of partial discharges in AC systems, but the same effect at HVDC level can cause serious damage to system, can anyone provide relevant information, test results on this sector.
We have the maximum rating of 6.5kV with 3kA switch this rating is not enough for high power conversion. So we are connecting discrete switches in series to achieve maximum rating high voltage switch.
I came across this term in the context of flash overs on the surface of insulators in vacuum.
When a traveling wave meets a short circuit, it is totally reflected
In order to develop dynamic model of arc propagation over insulator polluted surface, I’m looking for ideas concerning the use of FEMM at each time step simulation in Matlab to get the whole system electrical parameters.