Impedance - Science topic

after model analysis, use response dynamics for cycle event.

It looks to me as if the impedance you are talking about is in parallel with the feed, so you don't want it to be a short circuit but an open circuit, so quarter wave is right.

@vinod

If you found some solution kindly let me know.

I made the 4TP connections to 4294A and tested with the open - short calibration. But I'm not getting proper response such low impedance at short and high impedance at open condition even after calibration

1. Should I perform electrical length compensation or anything else to get a proper calibration?

2. How to do it in 4294A impedance analyzer?

Kindly update if you rectified the issue.

I guess it is done via observation of S-parameters using Vector Network Analyzer e.g. https://farran.com/farran-product-category/wafer-s-para-measurements/

Dear Francesco Gagliani,

you can see

Fitting of Electrochemical Impedance Spectroscopy data with Zview 3 2b!! #electrochemistry

Sorry, I don't have papers. They should be very easy to be obtained, or you can also search EIS + some topic, then EIS figures and their papers will come. As for the fundmental theory, I personally recommend Bard's book and Electroanalytical Methods from springer.

Hi dear Diego

I recently find out that I should do something with my circuit and your answer is right I made it closer to my point just by changing the circuit. Thank you for helping me Diego David da Silva

You can write the impedance function by inspection with Q as a 1/sC term and successive parallel to series combinations of each branch. There are symbolic network solvers that reduce the function to canonical form when possible. A Bode plot will also provide the critical frequency break points and time constants.

Thanks a lot Dr Hani

Edward J. Rothwell, Jonathan L. Frasch, Sean M. Ellison, Premjeet Chahal, and Raoul O. Ouedraogo, "Analysis of the Nicolson-Ross-Weir Method for Characterizing the Electromagnetic Properties of Engineered Materials," Progress In Electromagnetics Research, Vol. 157, 31-47, 2016.

doi:10.2528/PIER16071706

From S-parameters you may find the Z-parameters

You can use the symbolic approach, here an example

syms s

G=[1/(s+1) 1/(s+2);1/(s+3) 1/(s+4)];

lambda=eig(G);

f1=matlabFunction(lambda(1));

f2=matlabFunction(lambda(2));

w=logspace(-1,3,500);

bode(frd(f1(1j*w),w),frd(f2(1j*w),w));

Hey there Abu Faizal! So, when they talk about relaxing the system in the context of taking Electrochemical Impedance Spectroscopy (EIS), they mean giving the system some time to settle into a stable state before you Abu Faizal start measuring its impedance.

Now, why is this important? Well, some systems can be a bit temperamental. If there are any dynamic processes or reactions happening, they can introduce noise or instability into your impedance measurements. By letting the system chill for a bit, you're allowing it to reach a steady state, making your measurements more accurate and reliable.

To make sure the system is relaxed, you Abu Faizal typically wait for a sufficient amount of time after any perturbations or changes in conditions. This could involve stopping any applied potentials, letting reactions reach equilibrium, or stabilizing temperatures. The specific criteria depend on the nature of your system.

Checking if the system is relaxed involves monitoring relevant parameters or signals. For instance, you Abu Faizal might look for stable voltage or current readings, or ensure that any transient responses have settled down.

Remember, the goal is to capture the true impedance behavior of the system without interference from transient effects. So, take a breather, let things settle, and your EIS measurements should be smoother than a well-relaxed system!

yes

1- Characterization of Printed Podal Vivaldi Antenna (8–18 GHz) on RT Duroid with Single and Double Cavity.)

2-An improved wideband Vivaldi antenna design (utrgv.edu) (https://scholarworks.utrgv.edu/cgi/viewcontent.cgi?article=1170&context=leg_etd)

3-https://www.mdpi.com/2072-666X/14/7/1329

There are two components. Power loss due to power reflected back to the source and absorbed by the source (1-|S11|²) and loss in the matching circuit itself due to dissipation by the non-ideal reactive components.

What kind of organic coating and electrochemical set up do you use. I think that you have a problem with parameters of your set-up - a high impedance of coating and small impedance od EIS apparatus.

stefan

Standing waves can occur in transmission lines at power system frequency under certain conditions. When a voltage wave travels along a transmission line, it encounters a load impedance at the end of the line. If the load impedance is not matched to the characteristic impedance of the line, a portion of the voltage wave is reflected back towards the source. This reflected wave can then interfere with the original wave, resulting in the formation of standing waves.

The formation of standing waves in a transmission line is influenced by various factors, including the length of the line, the characteristic impedance of the line, the load impedance, and the frequency of the voltage wave. In particular, the relationship between the load impedance and the surge impedance of the line can affect the likelihood and severity of standing waves.

The surge impedance of a transmission line is the characteristic impedance of the line when it is assumed to be infinitely long. When the load impedance of the line matches the surge impedance, there is no reflection of the voltage wave, and standing waves do not occur. However, if the load impedance is higher or lower than the surge impedance, some of the voltage wave is reflected back, leading to standing waves.

In summary, standing waves can occur in transmission lines at power system frequency, and the relationship between the load impedance and the surge impedance of the line can affect their formation.

Impedance is measuring the overall health and performance of the battery. It can detect battery degradation, abnormal conditions, and aging to ensure proper maintenance and extend battery life. It helps monitor the battery's state of charge and capacity loss.

Hello! The expression √(L/C) is correct just for the determination of the characteristic impedance of lines with negligible losses. Try to use a complete formula that contains also dissipative parameters.

Dear Aitolkyn S. Uali ,

fitting(s) follow^[1] the (good) data.

So, try to reduce the AC-amplitude (V_AC<5mV) and remeasure, in order to reduce the high-frequency 'hook'-error(s).

_{1. A cart follows the horse, or 'A horse pulls a cart (not the opposite)'.}

Yes, Prof. , you are right. Perturbation theory works sometimes, but we must agree that there is not a unique approach to solving the kinetic equation.

I apologize for the late reply.

The reason why perturbation does not work always is that there are many physical phenomena that involve processes out of equilibrium with chaoticity and randomness, in addition to.

So sometimes if the problem can be linearized, then perturbation can be used, but sometimes.

Let us see, for example, superconductivity by only considering the T different from the 0 K case (Matsubara frequencies is usually and correctly named) and only taking into account the first term in the zero temperature energy gap (that takes into account self-consistency, or another example is the Vlasov equation in the case of linearization for plasmas is a wonderful example of linearization where perturbation theory applies as you stated.

Best Regards.

Thanks dears for your valuable answers

It seems from your answers that this kind of impedance combination is rather specific to the electrical engineering field. Am I right or are there applications in other scientific fields, especially in electrochemistry and electrochemical impedance spectroscopy (EIS)?

Thank you both. Yes, I agree it came from the instrument. In our case, the electrode we use cannot respond with high frequencies.

You should know that this is not governed by quarter wave transition rules. A quarter wave transformer transforms between two different impedances not two impedances that are the same. The flare will introduce an effective lumped capacitance at the join and may be to compensate for other parasitic inductance or capacitance at the transition.

It probably isn't, but it may just be a badly designed transition. Not everything in published papers is good, especially if that wasn't the main point of the paper.

Can anyone please provide density and accoustic impedance of CZTSe compound.

Ítalo César Porto Xavier Thank you very much for sharing the docs.

Dear Yash Senjaliya ,

These other papers could be useful for you:

Best,

Fran

It sounds like you want a single value to assign to resistance of the electrode, to simplify your analysis. If this is your intent, then my answer is no: that would oversimplify the system, and you would be ignoring important changes at the interface if you took that approach.

That said, there is a way used by most experimentalists to avoid the complexity of impedance and the likely confounders such as side reaction products with your electrolyte. I don't recommend this, since it often produces poor quality research. However, if someone is pressuring you to generate results that match those in other publications, the solution is to fit your EIS data to an equivalent circuit - R(RC) is popular but R(C[RW]) is more likely to match your pristine gold electrode - and ignore all data except the value fitted by your software to the last resistor, which is often called charge transfer resistance. This means your research will be dependent on the algorithm used by one proprietary fitting program, you won't know if the circuit is an appropriate one for your system, and you'll be hiding behind the poor practice repeated by others. Best of luck.

HFSS does not use B and D field data, so there is no way to calculate permeability, and permittivity. You can only define these.

I guess, your question is related to troubleshoot the data fetched by HFSS from Maxwell? It always creates many doubts since the results sometimes are bizare, and the thing is almost not documented. Unit conversion is often incorrect, and I would also check these parameters. But do not know how.

Dear Mohiedin. You may also try to use the Butler-Volmer equation, but neglect the exchange current because you are working in an area far from equilibrium

Hello,

impedance matching is the practice of designing the input impedance of an electrical load or the output impedance of its corresponding signal source to maximize the power transfer or minimize signal reflection from the load.

Some papers are attached.

Thanks,

Are you plotting the fields at a particular distance from the edge, or are these normalised far-field results? They look to me like the far-field scattering from the 50 wavelength square plate. I assume the plate is not 50 wavelengths square at 1, 2, and 3 GHz, but only at one of them, perhaps 3 GHz.

It is not possible to plot the far-field of a plane wave - it is a delta-function, so what you have is the polar diagram of the reflected wave, centred about 120 degrees, the polar diagram of the shadow the plate makes in the plane wave (see Babinet's principle), centred about 240 degrees, and low-level diffraction between these angles, and outside them too, but not so much.

I think your initial GO and GTD result (not PO) that you are trying to verify is in the near-field. The near-field for an infinitely long edge on a semi-infinite half-plane extends out to infinity.

Dear Haijun Ruan,

It was not possible to find this equation: "... the capacity change should be I/w*(1-cos(wt)).", in your existing paper^[1]. Maybe, It will be shown in your next, paper, plans.

_1.

If you want to measure impedance in a low cost way, get yourself

1) Suitable signal generator

2) An appropriately sized current sense transformer

3) a two-channel oscilloscope.

Measure the voltage and current as you vary frequency. Oscilloscope will give you the phase relationship between current and voltage across transducer. You can then calculate the real and imaginary components of impedance. I leave it as an exercise how you might calibrate this setup. Cheers!

In CST it is possible to look at the port mode fields that have been calculated. It probably is in other codes. Keep making the port bigger until the fields stop spreading wider when you make the port bigger. Also keep making it bigger until the port impedance stops changing.

Yes, it is possible.

The most straightforward way is through Ohm’s Law. By using a voltage sensor to measure the test signal's voltage across the transducer and using a current sensor to measure the test signal's current flowing through the transducer, together with various signal processing algorithms, the impedance over the frequency range of interest can be obtained. The test signal can be produced by a signal generator. As an alternative, you also can use the Inductive Coupling Method for the measurement of the impedance of the transducer. More information about these methods have been detailed in my following papers/monograph:

[1] Z. Zhao, "Measurement setup consideration and implementation for inductively coupled online impedance extraction," Ph.D. thesis, Nanyang Technological University, Mar. 2021, doi: 10.32657/10356/146738.

[2] Z. Zhao, A. Weerasinghe, Q. Sun, F. Fan, K. Y. See, "Improved calibration technique for two-probe setup to enhance its in-circuit impedance measurement accuracy," Measurement, 2021, vol. 185, Art no. 110007.

[3] A. Weerasinghe, Z. Zhao, N. Narampanawe, Z. Yang, T. Svimonishvili, K. Y. See, "Single-probe inductively coupled in-circuit impedance measurement," IEEE Trans. Electromagn. Compat., 2021, doi: 10.1109/TEMC.2021.3091761.

As an alternative, you can measure the grid impedance for the 400 V AC system directly. Please check our below publications for in-circuit impedance measurement:

[1] Z. Zhao, "Measurement setup consideration and implementation for inductively coupled online impedance extraction," Ph.D. thesis, Nanyang Technological University, advised by Prof. Kye Yak See, Mar. 2021.

[2] Z. Zhao, K. Y. See, E. K. Chua, A. S. Narayanan, W. Chen, and A. Weerasinghe, "Time-variant in-circuit impedance monitoring based on the inductive coupling method," IEEE Transactions on Instrumentation and Measurement., vol. 68, no. 1, pp. 169-176, Jan. 2019.

[3] Z. Zhao, K. Y. See, W. Wang, E. K. Chua, A. Weerasinghe, Z. Yang, and W. Chen, "Voltage-dependent capacitance extraction of SiC power MOSFETs using inductively coupled in-circuit impedance measurement technique," IEEE Transactions on Instrumentation and Measurement, vol. 61, no. 4, pp. 1322-1328, Aug. 2019.

[4] Z. Zhao, A. Weerasinghe, Q. Sun, F. Fan, K. Y. See, "Improved calibration technique for two-probe setup to enhance its in-circuit impedance measurement accuracy," Measurement, 2021, vol. 185, Art no. 110007.

[5] A. Weerasinghe, Z. Zhao, N. Narampanawe, Z. Yang, T. Svimonishvili, K. Y. See, "Single-probe inductively coupled in-circuit impedance measurement," IEEE Transactions on Electromagnetic Compatibility, 2021, doi: 10.1109/TEMC.2021.3091761.

Are you comparing a parallel plate electrochemical capacitor to an interdigitated one of the same materials/chemistry? In that case, you probably already know to use EIS to quantify capacitance using an equiv. circuit model. However, the geometry will give you substantial differences because of edge effects. Each corner of the interdigitated electrodes will cause a distortion of the stored field, so if you're looking for solutions in lit, try searching the term "edge effects".

Hi

For wave port, the impedance will calculate automatically using the actual port impedance you have for your structure so no need to renormalize and this usually what you have because in practice this will be the situation.

Please see the below link:

See this article

INVESTIGATION OF EFFECTIVE PERMITTIVITY AND PERMEABILITY FOR A NOVEL V-SHAPED METAMATERIAL USING SIMULATED S-PARAMETERS

Robert Lirette ,Hi Robert, thanks for the reply. I do optimize my circuit based on your reply. It helps. So now I can obtain the same results within the same day. But I still get different curves measured at different days. I am trying to find the factors. Thanks again.

Thirumal Vediyappan I am able to do what you are asking for. You are looking to run a Cyclic Charge Discharge (CCD) at constant current between your intended voltage range for a supercapacitor.

The way you do this on VersaSTAT is as follows:

Open a new experiment and in the experiment properties window (where it says actions to be performed) insert Chronopotentiometry. In the properties for chronopotentiometry use the current value you need and in the scan properties use data resolution (eg. time per point (s) = 0.001) and duration (eg. 200 s). In the limits use potential (eg. potential >=1 for aqueous capacitor or >= 2.7 or 3.0 V for non-aq capacitor). Then insert another Chronopotentiometry step, this time use a negative current (for discharge) and use same scan properties and put the voltage limit to <=0.

Now press shift and select both Potentiometry steps and keep pasting below. I typically do it 5 times (5 charge and 5 discharge steps).

Screenshot attached. Please let us know if this works?

In this case case I would go for a numerical evaluation which is rather easy these days..even if there is a formula somewhere it will be an approximation and not straightforward to solve

You can follow this review article for resistive switching and their measurements like Impedance Spectroscopy

Just because something is resonant and matched does not mean it will radiate. A resonant cavity can be matched, and will not radiate. However, it may be that your antenna is radiating and you are looking in the wrong direction or at the wrong polarization.

Dear Tanzila Noushin

The current in the electrochemical electrodes are composed of the following current components:

- The displacement capacitive current due to due to the electrode electrolyte capacitance

- The conduction current due to the charge transfer to the surface of the electrode.

If you scan the voltage you will have displacement current because such current is proportional to dV/dt.

If you measure your electrode under static conditions you will get only the charge transport current only.

The third current may be a form of interference or man made noise current because the impedance of the electrode is high in the range of the measurement.

I see that the if you increase the voltage further the current will increase appreciably pointing out the onset of the electrochemical reactions.

The other thing is that the rapid increase and fall with the voltage may be due to

some form of interference or noise or contaminated chemicals.

For typical electrochemical electrodes performance for water analysis please see the paper in the link:

Best wishes

Years ago I usually did that using an analogue potentiostat, a function generator and a plotter to draw the E/I Lissajous pattern for each frequency. Today you can use a data acquisition card to do the work: polarizing the cell through the potentiostat and recording the E/I output.

Use the De-embedding at the surface of the structure for getting the correct results.

I'm glad to see the question, because I meet the same problem. I want to know how you set the excitations and wether use the lumped port.

Mohamed Salah KAROUI

Ideal arrangement, use as much averaging or integration as possible. Operate the DUT on battery if an active device. If you are not in a screen room or a Faraday cage, making noise measurements is tough at best! That said, you can make a Faraday cage large enough to house the DUT and the measurement instrument using copper screen and a wooden box frame. Try running the test instrument on an isolation transformer. If you suspect low frequency noise degradation is a bigger issue, try obtaining mu metal as used in shielding CRT's. Make a mu metal shield for the DUT. Even steel chassis with some iron alloy added will assist.

Hi Kaushik

You probably have the attachment of the wires of the highlighted component in reverse. I suggest deleting the wires and reattaching

I do not have an exact answer. Maybe this reference can help it is a Maple worksheet if you have Maple software. https://www.maplesoft.com/applications/view.aspx?SID=154540

Lester Viray can you help him professor

This is not what you want, however you can read this article and gain some knowledge. Our project's end goal is same.

Before you start analysing the EIS data you should check that data are correct. This is done performing Kramersd-Kronig transform. In your case a si mple test shows that the data are incorrect.

prof V.S Muralidharan Sir i want to know the procedure of ink preparation from PANI and polypyrrole?

Dear Dr. Martin Burke,

It's very important for optimum potentiostat performance that the impedance of the Reference Electrode in your cell is low! A high impedance Reference Electrode will cause problems that range from simple overloads to potentiostat oscillation. When in doubt...check your Reference Electrode.

The impedance of your Reference Electrode should be less than 1 kohm. An impedance higher than 1 kohm is not good and an impedance higher than 5 kohm is unacceptable and must be corrected. With a Gamry Reference Electrode, the problem is easily corrected by changing the Porous Glass Frit.

You can find a “Testing Procedure” at:

A reference electrode with a gas bubble interrupting its electrolyte path has a very high impedance. The bubble can be produced by electrolysis, from deaeration gas, outgassing of a heated electrolyte, or from trapped air. You should always check that your electrochemical setup has an unbroken electrolyte path from the working electrode to the sensing element within the reference electrode.

Be especially careful if you reference electrode has a flat isolation frit. If this flat surface is horizontal within the cell, it can easily trap a gas bubble. A 45 degree angle on this surface allows natural convection to remove any bubble that tries to stick on this surface.

Luggin capillaries are also notorious for problems with bubble entrapment.

For more details, please the source of these info at: https://www.gamry.com/application-notes/instrumentation/reference-electrodes/

Best regards, Pierluigi Traverso

Dear Isuru Lakmal ,

the very simple R(RC) ECM (equivalent circuit model) is valid (only) at the (far) forward bias regime, both under:

1)dark [R(RC)]_dark, as well as under varying

2)illumination(s)^[1] [R(RC)]_{L_Fluxes}

conditions.

In reverse bias (regime), (ECM) things are more rich (and complex); but things seem to be much more interesting, as a materials' (and device's parameters) science tool.

So, in reverse bias, try the, quite good, ECM "R(R₁Q₁)(R₂Q₂)", both under dark and under^[1] illumination(s).

Fresnel equations

https://en.wikipedia.org/wiki/Fresnel_equations

There are some good designs of rf wireless power harvester in the literature. One may use a series resonance circuit between a low impedance antenna and the rectifier circuit. The series resonance circuit is composed of RLC wich is made to resonate at the rf frequency. The resistor is used to adjust the quality factor of voltage boosting series resonance circuit.Since the voltage is boosted then the rectifiers which are normally Schottky rectifiers will show low resistance compared to the impedance of the clamping capacitors in the ladder boosting network. Therefore the diode can be considered with linear I-V characteristics.

For more information of such a design please follow the paper in the link: https://www.researchgate.net/publication/318841662_Impedance_Matching_Antenna-Integrated_High-Efficiency_Energy_Harvesting_Circuit

Best wishes

Edgar Ulises De Los Santos Preferible medir desde 10KHz en una década a alta frecuencia no se pierde mucha información, pues solo verías la resistencia en serie ;)

Dear Dr. Santosh M. Bobade

I appreciate your taking the time to respond to me.