BetaSmart:

Online Training

Fast Charging Stations - High Efficiency Power Modules

Our Mission

We are a team of four people / for now / - two young engineers, a teacher of high energy physics with many years of experience in programming, and an organizer with extensive experience in managing inovative projects. In the portfolio of the two experienced team members are over 50 completed small and medium-sized projects. If we have the right like-minded people, we can accomplish something new - prepare knowledgeable people and provide them with the necessary experience to be able to work on proffesional projects, and all this - ONLINE, so that everyone can work from wherever they want.

Our Mission

We are a team of four people / for now / - two young engineers, a teacher of high energy physics with many years of experience in programming, and an organizer with extensive experience in managing inovative projects. In the portfolio of the two experienced team members are over 50 completed small and medium-sized projects. If we have the right like-minded people, we can accomplish something new - prepare knowledgeable people and provide them with the necessary experience to be able to work on proffesional projects, and all this - ONLINE, so that everyone can work from wherever they want.

Our Suggested Idea

Lets start with an idea from us. If our topic is not in your field, but the activity appeals to you, please contact us and we will discuss what we can do together, and if possible realize the idea.

LET'S BE CLEAR - The main goal of this activity is to educate and prepare specialists, so we can develop a project and potentionally form a business with the most interested people involved.

The main goal is educational but if the people involved have a great idea and want to move on with realising it, we can manufacture or develop a full scale project with our company or found a new company together.

Lets Start

Of course, we're not allmighty and we don't know everything. During our years of experience, we've learned that when you know how to do something but you can't fully accomplish it, the best thing to do is to continue pressing ahead untill you manage to do it.

We know that sometimes the process can be intimidating and our goal is to help and support each other to push trough the difficulties and complete the given idea to the end.

Lets Start

Of course, we're not allmighty and we don't know everything. During our years of experience, we've learned that when you know how to do something but you can't fully accomplish it, the best thing to do is to continue pressing ahead untill you manage to do it.

We know that sometimes the process can be intimidating and our goal is to help and support each other to push trough the difficulties and complete the given idea to the end.

Participants and Investors - Differences

There is a big diffrence between being a participant or an investor. As a participant, you are a part of our team and work with us remotely or on-site. As an investor, you are the person who invested capital in a project and uses the products completed, which is a serious endevour.

Participants

To be a participant in our team you must meet the following requirements:

• To have good computer skills
• To have productive/creative thinking
• To be a good problem solver
• Ability to work/learn new software environments
• Be able to explain the idea you are proposing in a comprehensible way
• To dedicate the necessary time to fulfill the commitments made to the idea
• Be able to work remotely.or onsight
• Possess different skills useful for our projects;

For us your experience and what you can actually do are more important than your degree of education.

Participate in Tasks

Investors

To be an investor is much different than being a participant. You need to:

• Be an entrepreneur
• Have a good risk evaluation
• Know atleast the techical basics of the project
• Be sure of the positive outcome of the project
• Be sure that every invested penny brings profit
• Meet all other requirements for being an investors
What Information you'll get from us:

We can present you the expected characteristics of the finished product - the result of the idea. Approximate cash flow according to our data, which you can adjust if you have additional or different information. Approximate cost of the required investment. Estimated time for production and certification of the product.

Become an Investor

How to be Sure that Your Idea is Protected?

For participants, we offer a confidentiality agreement and other legal documents that you may request. For the investors, all parties are protected by international law.

The confidentiality agreement can be viewed by downloading it below.

Confidentiality Agreement (rtf)

Download

Confidentiality Agreement (rtf)

Download

Technical Development

Checking the Idea

We're developing our own AC/DC power module for EV control. The goal is accomplishing high efficiency ( over 97.5% for the product ) and power output from 30kW to 100kW. We've selected as target output 80kW. This is only a part of the full project - the full data about it will be established on a later stage.

Checking the Idea

We're developing our own AC/DC power module for EV control. The goal is accomplishing high efficiency ( over 97.5% for the product ) and power output from 30kW to 100kW. We've selected as target output 80kW. This is only a part of the full project - the full data about it will be established on a later stage.

Participants

We expect everyone who has the opportunity to spare some time for the activity to join. If you are interested in joining, please fill out the contact form and fill in some information about yourself. Write what you want to do together and what you can do individually.

Block Diagram

A simple block diagram that does not need a special explanation for those who know. We suggest starting not the classic way, but from the part that can prove that the desired outcome is possible. For us it is 'AC/DC Converter Block'.

Block Diagram

A simple block diagram that does not need a special explanation for those who know. We suggest starting not the classic way, but from the part that can prove that the desired outcome is possible. For us it is 'AC/DC Converter Block'.

Power Scheme and Elements

In order to provide the required parameters, we have to choose a high voltage network, with a small number of electronic switches for minimal losses. We choose 3 by 400 Vac input voltage and if we make a delta type connection, we will have an operating voltage of the switches ~400 Vac. We present a network with alternating current switches composed of 2 MOS transistors connected in opposite direction, as shown in Fig.3.
In order to have an efficiency above 97.5% at 80 kW power output, the total losses must be below 2.5%, i.e. less than 1600 watts. We assume the ohmic losses in the transistors to be up to 0.55% or 440W. We have adopted leading and trailing edges with a total switching time of 300 nanoseconds at a frequency of 20 kHz.
We assume switching losses to be up to 200 W or 0.25%. After our calculations, we know that we need special electronic switches with an ohmic resistance below 0.05 ohms.
We are looking for a minimal resistance in the switched on state with a transition temperature of 125 degrees celsius, and current 80000 / (400-20%) / 3 = 83A. It follows from here the resistance in a switch on state must not be greater than 0.05 ohms of the switch.

Power Scheme and Elements Continuation

The operating voltage of the circuit is 400Vac (+/- 20%), i.e. less then 700V amplitude value. It is better not to have large voltage jumps which we control up to +20%. This results is in a max voltage of slightly less than 850 V. in the MOS switch. The operating voltage of the chosen transistor must be 1200V. With these parameters, the loss on the key elements is expected to be < 640W~ 0.8 %. From a review of commercially available transistors that meet these 2 parameters, the GE12047BCA3 type has an Rds on at 125 degrees C of about 0.0048 ohms and 1200 V max voltage.

The losses in it would be about 29 watts or less than 0.1% and together with the key losses less than 0.8%. This is excellent but due to its high price is needed only when the requirements are high. We calculate the losses in the remaining elements of the power scheme to get:

1. Losses in the power switches - 640 watts.
2. Additional 200 watts in the other elements of the power circuit.
3. Losses in the control circuit - about 30 watts and a total of 840 watts loss ( about 1.05%).

Very idealistic, isn't it? I personally would not put such elements. Here on this site we only check whether a schematic solution meets given conditions. We assume maximum losses of 1.5% which would make the block efficiency around 98.5% Looks like we are 1% better!

Power Scheme and Elements Continuation

The operating voltage of the circuit is 400Vac (+/- 20%), i.e. less then 700V amplitude value. It is better not to have large voltage jumps which we control up to +20%. This results is in a max voltage of slightly less than 850 V. in the MOS switch. The operating voltage of the chosen transistor must be 1200V. With these parameters, the loss on the key elements is expected to be < 640W~ 0.8 %. From a review of commercially available transistors that meet these 2 parameters, the GE12047BCA3 type has an Rds on at 125 degrees C of about 0.0048 ohms and 1200 V max voltage.

The losses in it would be about 29 watts or less than 0.1% and together with the key losses less than 0.8%. This is excellent but due to its high price is needed only when the requirements are high. We calculate the losses in the remaining elements of the power scheme to get:

1. Losses in the power switches - 640 watts.
2. Additional 200 watts in the other elements of the power circuit.
3. Losses in the control circuit - about 30 watts and a total of 840 watts loss ( about 1.05%).

Very idealistic, isn't it? I personally would not put such elements. Here on this site we only check whether a schematic solution meets given conditions. We assume maximum losses of 1.5% which would make the block efficiency around 98.5% Looks like we are 1% better!

Schematic analysis

We must note that according to the scheme and fig.2, 10 milliseconds are a long time and during this half-period 200 pulses pass through the transformer in one direction and the ferrite of the transformer will be saturated very fast, the current through the transformer and the transistors will grow rapidly and the transistors will defect.

The pulse graph is shown in Fig. 6. In order to avoid such cases, it will be necessary to make a large air gap, which leads to a number of inconveniences, i.e. this makes the transformer larger and more expensive. A big plus of this solution is the small number of power elements, and a relatively quick calculation of the circuit fig.3, fig.4 and fig.5, and as a drawback we get expensive elements for the switches.

This is a solution in which an alternating current will always flow through the winding of the transformer regardless of the polarity of the half-period of the mains voltage.

Schematic analysis

This power scheme gives us more power than the first, other conditions being equal. The only drawback is the large number of expensive electronic switches - 6 on each phase. If you want to choose them, you will have to use 24 switches, but the scheme will be unstable, expensive and with high losses.

Schematic Analysis

This power scheme gives us more power than the first, other conditions being equal. The only drawback is the large number of expensive electronic switches - 6 on each phase. If you want to choose them, you will have to use 24 switches, but the scheme will be unstable, expensive and with high losses.