A Power Lab

How high voltage willl the transformers have? you have to difine.

I have to arrange a complete laboratory in my company.

This lab will be suitable for high power application like development of drives up to 60kW, welding and solar. I would need some references for particular instrumentations, brands and models, like load benchmark for electric motor (AC dinamometer, regenerative power supply etc), power analyzer and all I need to arrange such lab.

Thanks in advance

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Sorry I afraid I don't understand the question.

The power source is coming from a medium voltage (20KV) outdoor cabin processing and It will supply the indoor cabinet in the lab at 380V ac. What is the power rating of the cabinet for supplying a 60kW motor taking into account that I am going to re-use a regenerative energy coming from the AC dinamometer?

I hope of answering your question

you mean 380v /60kw?

how ever I can off er you power analyzer, voltage and current analyzers etc.

you can also log in our chinesemade web site for details.

It's correct.

Could you give me the link of your website?

Thank you.

define voltage (not difine). I type wrong word.

Too little information is provided. To me a complete test lab could mean, well, a complete professional test lab - very expensive to setup and maintain and not something an average person can setup or run.

- What is the actual application? Is it a motor variable speed drive controller test area? You mention drive development and solar and welding? What do you actually want to test and what test results do you actually want?

- What are you trying to accomplish? Are you testing your own products? Are you testing brand new products? Are you testing products for certification to local standards? Are you just testing that a product works or are you trying to perform life-time analysis?

- What country is your company in and what is it your company does (or wants to do) with this lab? Why do you want an in house laboratory?

- What is your budget and staff allocation? If its only a small amount then that clearly indicates to me that you only want a basic test bench, not a laboratory.

- What is your qualification and level of experience? If it is only basic then you only want a basic test bench, not a laboratory.

I have my own accredited power test laboratory here and from your questions I don't think a 'laboratory' is what you want. Please provide MUCH more information, otherwise any answers I (or others) give will either be unsuitable for your application or so complicated and/or expensive that you will have no idea what we are talking about let alone if you need it or not.

I'm sorry I will try to be clear as better as I can.

I have to quantify, in terms of costs and instrumentation equipments, all I need for arranging a basic test lab, not very professional. Me and several persons will manage, maintain and run such lab.

We develop mainly hardware/firmware for high power application like variable speed drive controller for different kind of motors, inverters for solar systems and welding systems.

My company is based in Italy and what I want to accomplish with the new lab is a deep debugging of the systems we design and mainly to test the behaviour of our devices like power switches (IGBT, MOSFET etc..).

For example to test a three phase inverter for a variable speed drive up to 60KW with a DC BUS of 700V I need to drive a 60kW motor and a dynamometer that works as a load. In this case I need to know the amount of the installed power in the indoor cabinet, a bench test (brand at least) and all instrumentations should necessary to perform power measurements (i.e. scopes, current probes, power analyzer to measure the efficiency of the system under test and so on).

I'll try to have an idea of the budget but it is not a constrain. I have available a room of about 150 m2 (square meter).

I'm an experienced application engineer but I've never manage so higher power.

At the first time a basic test bench will be enough.

Thank you in advance.

Jack is good at inverters as I know from his threads before. he may give you a good idea at this position.

the site is madeinchina.com you can find it easily from google or yahoo etc. or find intrument net in china.

btw, I wonder how do you develop your inverter or switcher power supply if you havent got these basical instrument.?

larger or smaller are almost same at variables but different from values.

voltage, current, power, distortion, ppwer factors, power qualify,phases detector, loss of power and electronic loads etc.

I like to share the information iwth you. if you get more news.

I also want to knwo, do you test your inverter set or only switcher devices like igbt or mosfet etc? they need different instruments.

and a motor when it starts will absorb at least about as 3--4 times current as normal running.

etc.

Thank you for replying. We also have a lab for lower power application, i.e. lighting home appliance, power supply and so on. But I don't know some brands for high power dynamo meter and power supply (AC/DC) manufacturers.

I must perform the inverter hardware debug, Its efficiency curve by varying the motor load and also I have to test the behaviour the power switch in terms of switching and conducting losses.

Happy to share with you all information when I'll get more.

That narrows what you need down considerably.

Well one of the main devices you will need is going to be a variable motor load for the variable speed drive (VSD). I have worked with a few different types (resistive, friction, magnetic, water, inductive reactor) and the cheapest and easiest to implement seems to be a water load. In this case you simple get a tank of water and a large motor with a water pump attached. Water is sucked in to the motor from the bottom of the tank and then feed back into the tank on the top. A valve adjusts the flow and hence the load. A simple, and fairly inexpensive approach that can produce a surprisingly constant and adjustable load for running over long periods of time. Unlike other methods (such as big exposed banks of resistive wire) this type of load simulates the motor characteristics and implements it in a safe way (no exposed live terminals). All you need to do is ensure the water tank is big enough to ensure that the water has a chance to cool down (the motor is self-cooling due to its inbuilt fan) and ), that the tank doesn't leak. Oh and mounting the whole thing on a trolley helps.

Other types of magnetic or electronic loads may be better in some ways but are going to be far more expensive, and in the end you are probably better off spending the money on better test and monitoring equipment.

You will of course need all the other regular test equipment - Digital storage oscilloscope, True RMS multimeters, some sort of temperature logger, etc.

Finally, the safety equipment. If you are going to be testing then you will want to test to the very limits of the product and beyond. That means that components will eventually fail. Safety screens and fire extinguishers are important, especially at this power level.

First tho, I would advise looking at the relevant IEC or other international standards for the products you are going to test. This really needs to be your starting point and should give you a much better idea of the range of standard tests you should be doing and the proposed equipment needed, after all the products will need to comply with these standards and it is far easier to make design modifications while the product is in the initial test stages.

http://www.iec.ch/

You are right, the pump with the hydraulic circuit is the cheapest and the easiest, I saw it some time ago. But I need some more professional equipment, even if more expensive. I must have the possibility to choose the torque load or its profile and the system (VSD) must control it automatically.

Thank you for the safety equipment suggestion. I have never thought about it.

Development of drives up to about 60kW, welding and solar.. Hmmm ok

1st, you need a laborotory with several rooms, 1 will have dangerous gasses, this is for load testing of the welder, you'll not just be employing resistive testing be also welding testing, thus you'll be doing some welding, or a "bath" simulation of a welding load.

Solar would just be resistive loading to make sure your regulators can do as they have been designed to do.

Motor drives to 60kW, ok, your after a Dynomometer (or just called a engine dyno) you'll need a AC or DC supply that will control the field supply of the dyno, you should contact a dyno manufacturer they should have all this, the only thing you'll get from a dyno is a lot of heat, you can run a generator off the end and use that as a load, but I'm afraid you'll possibly burn that out, or it wont be suitable for load testing your drives.

for the dyno, you'll be wanting to test the motors at specific speed/torque points for periods of time, the dyno is a form of generator, but instead of the output of the dyno feeding your local grid, its feeding either a resistive load bank, or the power going in is trying to resist the rotating motion of the armature, or basically a electro dynamic braking, my friend has one of those units for race engine bench testing, all it has are 2 wires for powering the field, and some fans to pump cooler air thru the device, some are also water cooled.

First of all, I am focusing my attention to the motor drive bench test up to 60kW. Could you suggest a dyno manufacturers and the kind of engine dyno. Regarding the energy coming from the dyno I would feed my local grid instead of using a resistive load bank. In this way the local power cabinet must not supply the whole power I need. How does it work a electro dynamic brake? Could you give me some manufacturer reference.

Thank you in advance.

if your looking to bench load a 60kW motor, and your trying to tie the power back into your "local" grid, do you have about 60kW of loads on your grid? if you don't your going to find it hard pressed to load your motors if you cannot supply the required loading.

Generally, the load is expelled as heat, either thru air or liquid cooling.

You could contact "Teco" for their range of "Eddy-current" clutches/drives, and using your motor as the prime-mover, and then bolting the load on to the output shaft, or just bolting the output shaft to a flange plate with a known mass hanging off a balance arm, or what most people do, is to run it through a load cell, and the other side to a stationary surface, and the loadcell reading the torque.

If your insistant on producing your own power, then you need a motor-generator setup, say 25% over the rating of your expected motor rating, so as you don't destroy the genny every time you try a 60kW load, but still you have to supply the required loading.