We are using IKCM30F60GD for a 220V 200Hz 9A motor drive circuit with 8kHz sinusoidal PWM. We have the PCB ready and is driving the motor as desired.
However, we need to have protection for shorted motor windings, i.e. U-V or V-W or U-W shorted.
We have created a current sense circuit that creates a voltage well above 0.47V (limited to 3.1V) at I_TRIP pin in case of a high current(33mV/A), and this circuit rises I_TRIP voltage to 0.5V in 1.2usec. That trips the IPM successfully and shuts the output successfully. We have tested the circuit with down to 2 ohms instead of direct short, and it worked flawlessly.
However, when we go down near 1 ohm, or short, the IPM shuts down the output, however it dies. After it is dead, we have measured inbetween P,Nx,U,V,W and it seems like IGBTs are fine, we measure the same values as a non-faulty IPM. However, there is a diode reading of 1.7V on VDD to VSS with the multimeter(VSS on cathode lead).
And when we power the faulty IPM using only VDD and VSS pins with +15V, we have 200mA current drawn. And the heat on the package is coming from the point just in the upper side of pin 7.
Why is this happening?
Attached is the part of the package that heats up.Show Less
Thank you. Show Less
I'm considering using multiple IRSM005-301MH integrated half-bridges in an inverter for motor control applications. When there are voltage spikes due to motor inductance, I am concerned about the reverse recovery time of the body diodes causing shoot-through. For this reason, I am considering using external rectifier diodes across each half bridge.
The IPM selector guide claims that the CIPOS Nano line uses "motor drive-optimized fast recovery FETs." I have two questions:
1. For these fast recovery FETs, are external rectifier diodes necessary for motor drive applications?
2. Does anybody know what the reverse recovery time of the body diode is?
Thanks. Show Less
i am working for some months with the FOC library and some PMSM motors. The library is really good. Takes some time to set-up but I would like to try the new MCE tools: Designes and Wizard.
Besides, the new range of IPM's are really powerful: there are a lot of deivces, that cover the most frequent motor applications; in fact, you can easily drive motors from few watts to Kw.
In the field of domestic and semi-professional appliances, powers up to 1.000 watt cover the 90% of the possibilities.
Since the space is a critical aspect, especially in domestic and/or handy tools, I would like to underline there is some lack of information regarding the axuliary power supply current consuption.
I try to explain better: in order to reduce as much as possible the space and the cost of the circuit, most applications drive the motor directly from the MAINS: 110 or 220 VAC. This means that you only need an EMI filter, a bridge rectifier and a snubber capacitor.
If you do not care about the torque ripple if often happens that there is no snubber cap.
That said, there is the need to obtain an auxiliary voltage, from 12 to 18 Volt (best is 15 Volt DC), needed by the IPM for the logic parts, and also another 5VDC / 3.3 VDC for the microcontroller. Considering that the microcontroller section should need something between 10 to 30mA, it is CRUCIAL to
understand HOW MUCH CURRENT the Auxiliary Logic Part of the IPM needs to work correctly,
This is really important because you can build an auxiliary PS with very few components (consider for example the LNK30x series coming from Power Integrations, that need just teo diodes, and inductor and two caps).
But these solutions can drive up to 200mA.
How can we be sure that 200/250 mA are enough for our motor applications?
I made some tests, with a PMSM motor that has a power of 500 / 600 W rated power. The maximum speed is 12.000 RPM
Please find attached a couple of screenshots taken from a DSO Rigol DS1074.
The pictures show the voltage across a 10 Ohm resistor in series of a 15VDC Power Supply that drives a ICK10H60 IPM, a module for up to 10A applications.
As you can see, there is a relevant peak of current related to the PWM switching frequency. The PWM freq. of the FOC driver is setted a 16Khz.
I would like, if possible, to have more informations and more tables from INFINEON. I assume they made a lot of tests regarding this topic.
I am happy to further discuss and get deeper in this topic.
Fabio Show Less
I would like to know more about the NTC.
Why is the NTC useful and how can I use it to estimate my case temperature?
Thank you in advance! Show Less
Do you have a recommended power supply I should use in my design? I mean is there a way to figure out the best suited?
Ty in advance Show Less