IR2110 Stepper Motor Driver Design

[almotaz]

i try to make bipolar stepper motor driver i make two h bridge with ir 2110 motor supply volt 48 V motor work with no load and low speed and very low torque and mosfet heat up fast i try work at 31 Khz and try change it to 15 Khz and same problem change bootstrap capacitor from 4.7 mF to 22 mF and 47 mF and same problem i use circuit like :
use mosfet = IRFP064
D1 ,D4 =BY399
D2,D3,D5,D6 = 1N4148
R3 ,R4 ,R7 ,R8 =1 K ohm
R1 , R2 ,R5 ,R6 = 10 ohm and try change to 33 ohm
C2 , C6 =100nf
C1 , C5 =4.7 mf change 22 mf change 47mf
Vcc 12V
Vdd 5V
PWM 5V

 

[d123]

Hi. When I had a learning curve nightmare learning to make much smaller/lower voltage/current H-bridges correctly, hot transistor usually meant: a) a questionable schematic I'd copied; but usually it meant: b) my incorrect wiring of the bridge transistors, or c) BJTs/FETs too small for the current passing through them.
Have you checked that the voltage going into the gate of the FET isn't above the Absolute Maximum Ratings for VGS? Have you put any non-polarised capacitors across the respective motor terminals? Stupid question: have you Sherlock Ohmed the motor coils to be sure 1a + 1b and 2a + 2b are the right wires?
Is the motor 48VDC or is that the power supply voltage?
Perhaps if you post a schematic of the circuit you have made, maybe some-one else here on eda who is more experienced will be willing to look it over to help you - it's hard to guess what the problem may be from a list, I'm sorry I can't help much more than that.

 

[almotaz]

power supply volt 48 and I sure the motor correct wiring its work with another derive I don't connect capacitor cross motor winding I don't know what's value of it

 

[red_alert]

IRFP064 has a maximum Vds of 60V, which is not quite appropriate for driving an inductive load at 48V.

A heating MOSFET could also be a sign of cross-conduction. Have you designed any deadtime for the PWM signals?

 

[almotaz]

i has dead-time in my program i will make new board i will use irf1407 has Vds 75V is this will work or i need to change anything else

 

[d123]

Hi again. Sorry if I asked stupid questions... Maybe the/a problem is just what red-alert says about max VDS. It's not always possible, but when I can I try to de-rate most components so they don't even break out into a sweat/don't have to bear a heavy load of any kind . I imagine you can't start off low everything when testing then build up speed/frequency/voltage once it's working correctly?
A (non-polarised) capacitor across the motor terminals helps with the large current surge when a motor starts up, I imagine they are placed there as a small reservoir capacitor. I've even put MOVS as well as a capacitor across motors sometimes, just in case it defends the power supply against the motor tidal wave ripple at turn on and off of the motor, besides the "cage" diodes. Small motors in manufactured devices seem to usually have a ceramic 104 capacitor soldered directly to the terminals.
For what it's worth, in my small experience I'm used to transistor H-bridges that work with PNP/PMOS at the top and NPN/NMOS at the bottom to fulfil the push-pull necessary in order to do bi-directional driving, and I've only used the little L293D as a chip H-bridge with a tiny bipolar stepper motor, so 4 NMOS looks weird to me, even if it works.
I hope you've found some solution. If you have to using those specific transistors for a 48V motor, I have no idea if it's possible for this but it is for other stuff - maybe you could parallel two of them to split the voltage burden between the two.

 

[red_alert]

i has dead-time in my program i will make new board i will use irf1407 has Vds 75V is this will work or i need to change anything else

You may try some tests using a pure resistive load (a light bulb or a heating element). If the MOSFETs don't get hot anymore then the circuit it's OK but you have to manage to remove the switching spikes of the inductive load.

A highly rated Vds MOSFET could help. First of all, try to minimize the parasitic inductances (wires, PCB traces) between drivers and MOSFETs and between MOSFETs and DC-LINK (48V).

You could also try to slow down (at least) the low-side MOSFETs turn-off process by removing the diodes across the gate resistors.

As a last resort, you could try to add some sort of snubbers/TVS diodes across the MOSFETs/DC-LINK.

 

[FvM]

Your schematic shows 300V instead of 48V bus voltage. What else is different in your real circuit?

A high power stepper motor needs constant current drive, it won't be supplied by constant voltage. I don't see any means for current measurement in your circuit, how do you set the motor current respectively PWM duty cycle?