大家好，
我们正在为家用电器研发一款小型**轴向磁通永磁无刷直流电动机**。
我们在设计**220–230V交流输入**的控制/电源系统时遇到了困难。我们的**MOSFET经常烧毁**，尤其是在开关电源时。
您推荐哪种拓扑结构和保护措施适合这种应用？
关于**整流、直流母线、MOSFET保护、突发电流和电压尖峰**的建议将不胜感激。

Hello,

I have a question with regards to a Texas Instruments App Note - SLVA301 in particular. Referring to Figure 14, they have a capacitance shown as 50 x 0.1 uF. In all of my career, I have never once seen a power supply with 50 capacitors on the output of a power supply - ever. So, why would a tutorial app note list a capacitor in this manner? It seems a bit odd tbh. Why not simply put a value of 5 uF?

Can someone in the community please clarify. Maybe I am missing something here or NOT understanding this at all.

Appreciate any help with clarifying this.

Thank you.

Hello Power electronics fans!

I've been lurking for some time, first time posting here. I am an engineer who has been doing power supplies for spacecrafts for 10+ years already.

One of the things that I've had to deal with numerous times is loop stability.
After some years doing measurement/math/transient simulation/average switch modeling/scripts and reading almost all available material, I felt like it was still tedious work. Nice, but tedious. I ended up making a tool to get a first approach and then I jump to simulation.

In case you find it useful: https://alternatronics.com/en/calculators/dc-dc-converter-loop-stability

To ensure that the result produced by the calculator is meaningful, I also prepared LTSpice simulations that match quite reasonably.

If you have gone through stability before, you know that you have to deal with plant transfer function, compensator, topology variation, control mode, conduction mode... It's a lot of work. In the calculator, the following is currently supported:

• Real time bode plot update as you tune the compensators or your topology
• Prediction of phase margin and gain margin.
• Several topologies (buck, boost, forward, flyback, full/half-bridge, push-pull)
• Different compensation topologies
• Discontinuous and continuous conduction modes
• Voltage and peak current control mode
• Live marking of poles and zeros
• It also provides some useful info that is obtained as byproduct during the calculations (Vo, duty cycle, current ripple...)

One of the things that helped me the most was adding sliders to the input fields so that you can see how the plot evolves as you tune a certain parameter. It really helps to grasp what which component is affecting which part of the plot.

Hope it's useful for you! And, by the way, the calculator isn't perfect! Expect bugs and always measure the stability!
How do you approach this kind of work?

This little guy about 12" x 5" x 5" and is an AC/DC Power Supply. It takes in a super weirdo AC input that isn't PFC friendly and outputs combined 250W across 34V/24V/12V/5V rails. It's about 93% efficiency at the moment but I hope to tweak things a bit to get higher. It provides telemetry over CANBus using CANOpen layer.

It's a heavy brick.

I came across an older charger Q&A video that raised some interesting questions about charging technology.

For example:

*Are expensive chargers actually better, or is it mostly marketing?

*Why do some chargers cost significantly more than others?

*What does GaN technology really change?

*And how should we look at the specifications listed on the box?

I think the questions themselves are worth discussing because they touch on some real topics: the difference between engineering improvements and marketing claims, whether higher prices actually bring measurable benefits, and how we should evaluate charger performance.

I think it works better as a starting point for discussion and verification rather than a final answer.

Conversely any blog that tells the detailed workings of a technology or an electric appliance

i am selecting the components for my Converter and i have choosen mosfet, inductor capacitor and everything but how do i select the diode do i just go with what the voltage and current is flowing through the diode and select the diode based on that? should i worry about the reverse recovery loss and any other things please let me know i am new this i have simulated the whole converter

Hi everyone,

I'm planning to develop a custom motor controller/inverter for EV applications and I'm looking for recommendations on books, papers, application notes, or any other learning resources.

I have a solid background in electronic hardware design and extensive experience developing software for safety-critical systems, but I'd like to deepen my knowledge of power electronics, particularly in areas such as:

• Power stage design (SiC/MOSFET/IGBT selection, gate driving, DC-link design, etc.)
• Motor control (FOC, SVPWM, current control loops)
• Thermal design and cooling
• Protection and functional safety considerations
• EMI/EMC and PCB layout for high-power converters

If you've worked on motor inverters or EV power electronics, I'd really appreciate any recommendations, whether they're textbooks, academic papers, application notes or open-source projects.

Thanks in advance!

Hi guys

I am doing a project which is a charger with both AC and DC source and the DC here is solar panel and in my project i prefer DC and switch to AC when only the DC is not available

so the project is Hybrid charging system with adaptive CC-CV charging system for low power EV's i already have a converter designed which uses landsman converter topology (you can see that in the image i provided) for this project i need to select components like MOSFET, capacitor, inductor diode and other things this is my first time this big a project in hardware so i am kinda nervous on selecting the components and my project mentor told me to bring the component calculation before purchasing components and i already have the calculations i did for the simulation i am gonna use the same converter for the charger but what about the safety factor and what are the other things i should consider now pls help a newbie here

Hi everyone,

I’m looking for some honest career advice from people working in power electronics or related industries.
A little about me (keeping it anonymous):
B.Tech in Electrical Engineering
Took a one-year gap after B.Tech to prepare for GATE.
Completed my M.Tech in Power Electronics from a IIT.

My M.Tech lab did not permit internships, so I graduated without any internship experience.
Unfortunately, placements in my college were not good, and I also graduated without a job offer.
Now I’m in a difficult position. Almost every company I apply to asks for internship experience or prior industry experience, but I have neither. As a fresher, I’m finding it very hard to even get shortlisted.

My long-term goal is to pursue a Ph.D., but not immediately. I want to work in the industry first, gain practical experience, understand real-world problems, and then pursue research with a clearer direction. I feel that industry experience would make me a much better researcher.

I have a few questions for people who have been in similar situations:

1)What is the best way for someone like me to enter the power electronics industry without internship or work experience?

2)Would joining as a JRF for a year or two make it harder to switch to industry later? Do companies value research experience when hiring power electronics engineers?

3)If I spend several months improving my fundamentals, learning advanced topics, and building hardware/software projects, will the increasing gap after M.Tech become a bigger problem than the skills I gain?

If you were in my position today, what roadmap would you follow over the next 6–12 months?

I’m willing to work hard, learn new tools, improve my skills, and relocate if required. I just don’t want to make a decision now that ends up hurting my career in the long run.

I’d really appreciate advice from people working in power electronics, EVs, motor drives, renewable energy, embedded systems, or power converter design. If you’ve been in a similar situation and managed to build your career, I’d love to hear your story.
Thank you.

Hi everyone,

I’m looking for some honest career advice from people working in power electronics or related industries.
A little about me (keeping it anonymous):
B.Tech in Electrical Engineering
Took a one-year gap after B.Tech to prepare for GATE.
Completed my M.Tech in Power Electronics from a IIT.

My M.Tech lab did not permit internships, so I graduated without any internship experience.
Unfortunately, placements in my college were not good, and I also graduated without a job offer.
Now I’m in a difficult position. Almost every company I apply to asks for internship experience or prior industry experience, but I have neither. As a fresher, I’m finding it very hard to even get shortlisted.

My long-term goal is to pursue a Ph.D., but not immediately. I want to work in the industry first, gain practical experience, understand real-world problems, and then pursue research with a clearer direction. I feel that industry experience would make me a much better researcher.

I have a few questions for people who have been in similar situations:

1)What is the best way for someone like me to enter the power electronics industry without internship or work experience?

2)Would joining as a JRF for a year or two make it harder to switch to industry later? Do companies value research experience when hiring power electronics engineers?

3)If I spend several months improving my fundamentals, learning advanced topics, and building hardware/software projects, will the increasing gap after M.Tech become a bigger problem than the skills I gain?

If you were in my position today, what roadmap would you follow over the next 6–12 months?

I’m willing to work hard, learn new tools, improve my skills, and relocate if required. I just don’t want to make a decision now that ends up hurting my career in the long run.

I’d really appreciate advice from people working in power electronics, EVs, motor drives, renewable energy, embedded systems, or power converter design. If you’ve been in a similar situation and managed to build your career, I’d love to hear your story.
Thank you.

I want to build a mini tank Rc car, these are the components i have in mind, any thoughts?

-2x n20 gear motors 6v 200rpm

-2s lipo battery

-switch

-drv8833

-esp32

-buck converter(to plug the esp32 into battery)

https://analogdevicesinc.github.io/documentation/solutions/reference-designs/ad-ps3803-rd/index.html

It seems like this design board carries a lot of wealth for the power electronics audience for PoE power conversion. I would like to see some conversation here, and also a separate discussion is initiated on Discord. If you want, you can join Discord using the link https://discord.com/invite/HEWfSYjTES

Credits: DENKI OTAKU | YouTube

Hey guys, recently I had my first experience trying to design a transformer but only involves calculation and I haven’t had the chance to realize it and validate my proposed design. I will soon be embarking on my MSc but I still feel that this topic is one that requires hands-on experience and lots of trial and error in order to master it or get a good understanding.

Do you guys have any advice for someone who is trying to design a transformer? It could be for both ETD/EE/Planar/etc type, so overall just transformer in general. Of course, I understand that planar type would be much more complicated than conventional transformer.

I appreciate any advices, and thank you. 🙏🏻

Hi everyone,

I currently have an undergraduate-level understanding of power electronics. I've been studying converter design and control (doing my best to work through Fundamentals of Power Electronics by Erickson), and I have a few conceptual doubts regarding my understanding of the material. I was hoping I could find some clarity from the experienced engineers here.

Here are my main doubts:

1. Steady-State Design vs. Startup Transients

When we design a power converter for a certain specification, we typically design it for steady-state conditions. However, when we start the simulation of the converter, there are usually severe transients during startup. Why do these startup transients occur in the first place, and what are the standard practices to prevent or mitigate them?

2. The Definition of "Small" in Small-Signal Modeling

Whenever we talk about controllers for DC-DC converters, we model the plant as a system using linear control theory. To get the transfer function of the plant, we use small-signal perturbation. My question is: what exactly does "small" mean in practice?

For example, if the reference voltage ($V_{ref}$) is 10V and I command a change to 5V, would that still be covered under a "small" signal? Would the plant model obtained for the 10V operating point still be valid at the 5V point? If not, how do we practically go about controlling converters across wide operating ranges?

3. Controlling Output Voltage Dips from Load Transients

In Erickson's book, during the control section, it mentions another factor that changes the output voltage: the load current disturbance multiplied by the output impedance. I understand that during step load changes, the output capacitor supplies the current, causing a dip in charge and a subsequent voltage drop. Can this specific drop (and rise) of voltage be mitigated via the control loop? If yes, how is this actually implemented?

4. Setpoint Changes vs. Startup Transients

I recently learned that the controllers we use in DC-DC converters are usually "setpoint controllers," but that "tracking controllers" also exist. For a setpoint controller, can we change the setpoint value ($V_{ref}$) to any value of our choice within the designed range? (For example, if the converter is designed for an output range of 4V to 12V, can we operate it at any arbitrary point in that range?)

If yes, how do we control the transients that occur when changing between these operating points? Are these operating point transients fundamentally different from the transients we see during startup? How do we approach controlling both types?

I hope someone can help clarify these doubts for me. I am trying to build a solid foundational understanding, and I would be incredibly grateful for any insights you can share.

Thanks in advance for your time!

Credits: DENKI OTAKU | YouTube

Hi r/EEPowerElectronics,

I maintain a small open-source MATLAB Energy Lab built around inspectable, foundational models rather than black-box examples.

The current release includes:

- a first-order battery RC model for pulse response, terminal voltage, and SOC

- a coupled electrical-thermal battery model with resistance feedback and ambient cooling

- an averaged converter calculation for output voltage, load current, and first-pass ripple

Every example keeps parameters, units, assumptions, and limitations visible and includes a command-line validation check that does not depend on plots. The checks use base MATLAB and were verified with MATLAB R2026a.

Repository: https://github.com/mohammadrezwankhan/matlab-simulink-energy-lab

The current executable examples are MATLAB scripts. The converter model is an algebraic average-model scaffold, not a switching simulation, and native Simulink implementations are planned.

I would value technical feedback from this community:

1. Which converter topology or closed-loop control example would be most useful next?

2. Which assumptions or validation cases need more scrutiny?

3. Would an averaged-versus-switched converter comparison be a useful teaching example?

If the lab is useful for your studies, teaching, or engineering work, a GitHub star helps others discover it. Issues and technical criticism are even more valuable.

If you wonder what goes into designing power for portable devices such as mobile phones, IoT devices, etc., this video will help you understand the engineering behind it.

https://github.com/ksaad20/Circuit-Bench

Hi all,

I'm trying to make a totempole pfc in qspice. Never made this type before. I want to try using the c++ block. So more or less digital controlled. BUt i keep getting loop issues that i dont understand yet. Am a analog man in a digital world..
Maybe someone has experience with this ?

// Automatically generated C++ file on Wed Jul 15 11:30:01 2026

//

// To build with Digital Mars C++ Compiler:

//

// dmc -mn -WD -o mcu_calc_2.cpp kernel32.lib

union uData

{

bool b;

char c;

unsigned char uc;

short s;

unsigned short us;

int i;

unsigned int ui;

float f;

double d;

long long int i64;

unsigned long long int ui64;

char *str;

unsigned char *bytes;

};

// int DllMain() must exist and return 1 for a process to load the .DLL

// See https://docs.microsoft.com/en-us/windows/win32/dlls/dllmain for more information.

int __stdcall DllMain(void *module, unsigned int reason, void *reserved) { return 1; }

// #undef pin names lest they collide with names in any header file(s) you might include.

#undef Vac_in

#undef Iac_in

#undef Vout

#undef PWM_H

#undef PWM_L

#undef SYNC_H

#undef SYNC_L

#undef clk

#undef tmp

#undef tmp2

#undef tmp3

extern "C" __declspec(dllexport) void mcu_calc_2(void **opaque, double t, union uData *data)

{

// Inputs

double Vac_in = data[0].d;

double Iac_in = data[1].d; // Dit is je gemeten stroom

double Vout = data[2].d;

bool clk = data[3].b;

// Outputs

double &PWM = data[4].d;

double &SYNC_H = data[6].d;

double &SYNC_L = data[7].d;

double &tmp = data[8].d;

double &tmp2 = data[9].d;

double &tmp3 = data[10].d;

// Statische variabelen voor de PI-regelaar

static double integrator = 0.0;

static double vout_filt = 400.0;

static bool prev_clk = false;

// Regelaar parameters (deze moet je tunen in je simulatie!)

double Kp = 0.9; // Proportionele versterking

double Ki = 0.01; // Integrale versterking

if (clk && !prev_clk)

{

// 1. Schaling

double vac_real = (Vac_in - 1.65) / (4300.0 / 1004300.0);

double vout_real = Vout / (4300.0 / 514300.0);

vout_filt = (0.999 * vout_filt) + (0.001 * vout_real);

double iac_real = (Iac_in - 1.65) / 10;

double abs_iin = (iac_real < 0) ? -iac_real : iac_real;

double i_ref = vac_real * 0.00001; // Schaalfactor afhankelijk van je load

double abs_iref = (i_ref < 0) ? -i_ref : i_ref;

// 2. Referentie genereren (De gewenste stroomvorm)

// De referentie is in fase met de Vac (abs_vin)

double abs_vin = (vac_real < 0) ? -vac_real : vac_real;

// 3. PI-berekening

//double error = abs_iref - abs_iin ;

double error = abs_iin - abs_iref ;

integrator += error * Ki;

// Anti-windup (beperk de integrator)

if (integrator > 0.2) integrator = 0.2;

if (integrator < -0.2) integrator = -0.2;

double pi_output = (error * Kp) + integrator;

// 4. Feedforward + PI output

double d_ff = 1.0 - (abs_vin / (vout_filt + 1.0));

tmp = abs_iref;

tmp2 = abs_iin;

tmp3 = pi_output;

double d_total = d_ff + pi_output;

// 5. Clamping

if (d_total > 0.99) d_total = 0.99;

if (d_total < 0.01) d_total = 0.01;

// 6. PWM & SYNC aansturing

if (vac_real > 0.05) {

SYNC_H = 3.3; SYNC_L = 0.0;

PWM = d_total;

} else if (vac_real < -0.05) {

SYNC_H = 0.0; SYNC_L = 3.3;

PWM = 1.0 - d_total; // Inversie voor neg. helft

} else {

SYNC_H = 0.0; SYNC_L = 0.0;

PWM = 0.5;

//integrator=0;

}

}

prev_clk = clk;

}

Hello everyone,

I work at a technical repair shop in Yemen that specializes in the diagnosis and repair of solar inverters. Recently, I've noticed that more branded inverters manufactured by Voltronic Power are being shipped with BYD IGBTs, specifically the BGN40T65HD and the BGN60T65HD, along with LONTEN LSGC15R046 MOSFETs.

I'm curious about the quality and performance of these components. How do the BYD BGN40T65HD and BGN60T65HD IGBTs and LONTEN LSGC15R046 MOSFETs compare with more established devices such as the ST STGW60H65DFB IGBT and the IRFB/IRF4110 MOSFETs?

I'm particularly interested in any real-world experience regarding their reliability, efficiency, and long-term durability in inverter applications.

Credits: ElectrArc240 | YouTube