Difference between revisions of "RC10Kicker1Errata"
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(Created page with 'The prototype was manufactured on a barebones process so some errors have been incurred as a result. ==Current Limit== The current limit measures current through the silicon not...') |
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| − | + | Despite being a fairly mature design, there are quite a few wrinkles in the kicker board. Furthermore, it seems to be much lower impedance than the last design and produces far more power (250V @ 360++A). This kills our silicon. | |
==Current Limit== | ==Current Limit== | ||
| Line 7: | Line 7: | ||
# Thus, when the IGBT switches on again (nearly instantaneously) it sees the current running in the flyback/solenoid + new current. This destroys the silicon | # Thus, when the IGBT switches on again (nearly instantaneously) it sees the current running in the flyback/solenoid + new current. This destroys the silicon | ||
| − | The solution is to measure the | + | The solution is to measure the current running in the solenoid. I'll put up a modified schematic. |
| + | |||
| + | Also, there are a few problems associated with this section of the circuit | ||
| + | * Shunt resistor is underrated. Burned up one during testing. | ||
| + | * The gate resistors may have too little power though this is probably related to the failure of an IGBT during testing. | ||
==Barebones Layout Issues== | ==Barebones Layout Issues== | ||
| + | The prototype was manufactured on a barebones process so some errors have been incurred as a result. | ||
* Traces running under isolated power supply can be shorted on mounting feet of supply | * Traces running under isolated power supply can be shorted on mounting feet of supply | ||
| Line 18: | Line 23: | ||
==Misc== | ==Misc== | ||
* Fuses soldered into holders | * Fuses soldered into holders | ||
| + | * Jumper for the safe side logic power is far too large | ||
==Future Features== | ==Future Features== | ||
* Space to add additional IGBT with separate gate drive resistor for each output | * Space to add additional IGBT with separate gate drive resistor for each output | ||
| + | * The ability to easily disable the current limit by removing or adding a part | ||
| + | [[Category: RC Electrical]] | ||
| + | |||
| + | [[Category: 2009-2010]] | ||
Latest revision as of 20:02, 24 May 2020
Despite being a fairly mature design, there are quite a few wrinkles in the kicker board. Furthermore, it seems to be much lower impedance than the last design and produces far more power (250V @ 360++A). This kills our silicon.
Current Limit
The current limit measures current through the silicon not through the solenoid. When using the circuit
- The IGBT switches on
- The IGBT switches off when a programmed current limit has been reached. Thanks to the flyback diode, that current still runs in the solenoid.
- Thus, when the IGBT switches on again (nearly instantaneously) it sees the current running in the flyback/solenoid + new current. This destroys the silicon
The solution is to measure the current running in the solenoid. I'll put up a modified schematic.
Also, there are a few problems associated with this section of the circuit
- Shunt resistor is underrated. Burned up one during testing.
- The gate resistors may have too little power though this is probably related to the failure of an IGBT during testing.
Barebones Layout Issues
The prototype was manufactured on a barebones process so some errors have been incurred as a result.
- Traces running under isolated power supply can be shorted on mounting feet of supply
Mechanical Issues
- Solenoid connector interfere with underlying screw
- Battery connector interferes with underlying screw
Misc
- Fuses soldered into holders
- Jumper for the safe side logic power is far too large
Future Features
- Space to add additional IGBT with separate gate drive resistor for each output
- The ability to easily disable the current limit by removing or adding a part
