Need Helpful Comments and Suggestions On Electric Motor Dynamometer Bench Build

[D.Stan]

I am new to the Dynamometer Scene. I have learned a ton from this forum and I absolutely love it.

Needs:
Test AC and DC motors
120v to 480v
single and 3 phase
10-20HP

Retrieve Amps, Torque, Vibration, Temperature, and any other bells and whistles.

Like I said I am new to this particular scene and I have to start somewhere. I have a motor and I want to use it as the Load Generator. If you could please tell me what your thoughts are about this motor and what types of motors I can test with this particular Load Motor.

Specs:

Reliance Electric
20HP
1760RPM
460V
3Phase
Code G
Insulation Class F
TEFC
24Amps
Master Duty XE
60HZ
Power Factor 84.4
Type P
Design B

Very close to the Baldor CECP2334T-4 Bit not exactly. Specs

http://www2.baldor.com/products/spe...0&voltage=460&enclosure=TEFC&winding=&rating=

I am waiting on baldor to send me a specs sheet on my motor.

I have not decided yet on a energy dissipate. I am pretty sure I will choose a electric element and water.

I thank you for your time and input. This will help me out a ton.

 

[LionelHutz]

Looking at that Delta drive, it appears to be part of the C2000 model series and I have a hard time believing it does line regen since it's not mentioned anywhere as a feature in the Delta literature or on their website. It seems you need to add a REG2000 series unit to get regen capability.

 

[waross]

http://www.deltaacdrives.com/delta-vfd150c43ae/[/URL]]Braking Type: DC Injection;Dynamic Braking;AC Line Regenerative
AC Line Regenerative?: Yes

BUT

http://www.deltaelectronicsindia.com/Products/IABU-REG-2000-Series.html[/URL]]A traditional drive system used for inertia load work generally performs rapid deceleration, braking and positioning. When its motor is in generator mode it produces large amounts of regenerative energy that must be consumed to maintain a stable DC bus voltage and safe operation. The traditional method to solve the regenerative energy problem is to install a brake resistor. While it is easy to install and is low cost, it takes up a large amount of space and requires installing additional devices to dissipate the heat. This method provides limited efficiency and wastes the regenerative energy.

Delta's REG2000 series is capable of collecting and converting your system's regenerative energy into reusable electricity for the ultimate in energy savings. The installation process is as simple as installing a brake resistor, but with only half the size and better efficiency. The REG2000 is your best green energy solution for power regeneration.

Good call Lionel.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[LionelHutz]

Ya. deltaacdrives.com is a re-seller, not the manufacturer and they purposely pick a name to make it appear they are the manufacturer. Are you really going to believe everything they put on their website?

 

[cswilson]

iceworm:

What I envision is an inverter section that can be gated to send power back to the DC bus. Then a GTO type device that monitors the DC bus voltage, and pulls power from the DC bus and sends it to the braking resistor.

Any 4-quadrant drive has the capability to "send power back to the DC bus". That is what distinguishes it from a 2-quadrant drive. If torque is applied in the opposite direction sense from the motor velocity, which occurs in the added 2 quadrants, the motor becomes a generator, and the generated electrical energy must go to the DC bus stored energy. (In a transistor-based drive, the current just flows through flyback diodes to the bus.)

The drive is constantly monitoring the DC bus voltage, often through a simple voltage divider circuit, and if it gets above a certain level (above what the line input would provide, but below the shutdown voltage), an electronic switch is turned on to allow current to flow through a shunt resistor. Often this is a power transistor, and some drives use pulse-width modulation to control how much current is dumped. On higher-voltage drives, thyristors can be used for this function.

Curt Wilson
Omron Delta Tau

 

[itsmoked]

It's very hard to actually find regenerative drives. I went around in circles until I found 'brochure' gibberish that said "instead of wasteful braking resistors". seems I still missed the 'special part number'.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[itsmoked]

Thanks for the heads-up Lionel and Bill thanks for the link to the REG2000.

Very interesting to see they actually bolt another half VFD onto the bottom of the standard drive. That kinda makes sense actually. It also points out that a regen drive will be about %50 bigger than a standard drive so you can identify a regen drive by size/capacity inspection.

Thanks Curt for clearing up that a 4-Qaudrant drive does not necessarily infer a regen drive.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[LionelHutz]

Pretty much every IGBT based VFD will operate in all 4 quadrants. Even simple V/Hz drives will do it.