how to control or monitor voltage, temperature and current in IGBT from fpga

[Altera_Forum]

can anyone suggest me how to write a VHDL code to control or monitor voltage, temperature and current in IGBT gate drive via Quartus II cyclone development kit EP2C20F484C7N fpga..???

[Altera_Forum]

--- Quote Start ---  can anyone suggest me how to write a VHDL code to control or monitor voltage, temperature and current in IGBT gate drive via Quartus II cyclone development kit EP2C20F484C7N fpga..???  --- Quote End ---  No, they cannot, you haven't really provided any information, or any indication that you have done a little research.  FPGAs are digital devices, with logic level I/O pins.  How does the IGBT need to be controlled? On/off control, PWM control, or what?  Monitoring voltage, and current can be done using an analog-to-digital converter (ADC). Temperature can be measured using a temperature sensor with an internal ADC, or with another ADC and a voltage-output sensor.  There are plenty of SPI ADCs that are easy to interface to FPGAs.  My recommendation would be to first get your IGBT circuit designed in a simulation program like LTspice, using ideal voltage sources (configured for PWM generation if necessary), and voltage/current sense points in the design. Post that circuit, and it'll be clearer what voltage levels and currents need to be sensed. If you have analog circuit design questions, then ask those on the LTspice group (though if they are not LTspice related, you may get referred to an electronics design group).  Cheers, Dave

[Altera_Forum]

The answer is simple and not particularly related to FPGA. You can monitor all signals that are measured and digitized in your IGBT driver hardware. Connecting the digital signals to an FPGA development kit is probably the lesser part of the problem.

[Altera_Forum]

Hello Dave,  

Thank you so much for your response, with respect to the Space vector modulation index "m" pulse should be given to the IGBT driver. for ex. 10ms in state s1 and next 10ms in and so on s2, s3, s4, s5, s6. By switching this way it will produce sine wave as output with the variable amplitude and frequency. In the voltage source inverter we have 6 states as mentioned above and two null states.  Regards, Navin R

[Altera_Forum]

--- Quote Start ---   Thank you so much for your response, with respect to the Space vector modulation index "m" pulse should be given to the IGBT driver. for ex. 10ms in state s1 and next 10ms in and so on s2, s3, s4, s5, s6. By switching this way it will produce sine wave as output with the variable amplitude and frequency. In the voltage source inverter we have 6 states as mentioned above and two null states.   --- Quote End ---    An FPGA can easily generate such waveforms to the gate drivers.  However, that does not clarify your requirements; what current and voltage do you want to measure? For example, do you want to measure the instantaneous current and voltage during the time each of the IGBTs is active, or just the voltage and current delivered to the load?  The speed at which you want your monitored voltages and currents determines your ADC sampling rate requirement.   The resolution of the ADC is determined by the ratio of the largest to smallest value you want to measure for any particular current or voltage, eg., if you want a range of 1V to 1mV, you need an ADC with 10-bits of dynamic range.  Cheers, Dave

[Altera_Forum]

Initially, it should sense or monitor voltage and current at the input of the drive and at the load as well. Is that possible to measure continuous value..???  

 As you said it has a Max. Voltage of 30V and Current of 15mA. Is that possible to operate it with the 50kHz clock frequency..? coz in the Alter circuit board we have clock signal of 50MHz.  Regards, Navin R

[Altera_Forum]

--- Quote Start ---  Initially, it should sense or monitor voltage and current at the input of the drive and at the load as well. Is that possible to measure continuous value..???    --- Quote End ---    Think of the waveforms you see on a digital oscilloscope. These are samples from an ADC at a particular timescale, eg., a 50MHz ADC samples every 1/50MHz = 20ns. When you plot those samples over several microseconds scaled to units of volts, it looks like the original analog waveform.   You can do that in an FPGA if you like, but if you already have an oscilloscope for looking at those waveforms, why bother?  You need to figure out exactly what the FPGA needs to measure, if that measurement is used as part of a control loop.    --- Quote Start ---   As you said it has a Max. Voltage of 30V and Current of 15mA. Is that possible to operate it with the 50kHz clock frequency..? coz in the Alter circuit board we have clock signal of 50MHz.   --- Quote End ---    Measuring a voltage of 30V and current of 15mA is fine. You just need to design the ADC circuit appropriately.  The FPGA clock can be 50MHz or higher using a PLL. The IGBT gate drivers can be operated at kHz frequencies. Its up to your logic in the FPGA to generate the slower IGBT gate drive signals. Those signals can be generated using counters clocked at 50MHz, and a state machine to sequence the gate driver pulses.  Cheers, Dave

[Altera_Forum]

To get an idea about a typical FPGA to power electronics interface, you should review the FalconEye reference design available from ebv.com.

[Altera_Forum]

Just use an ADC externally with your voltage and the temperature sensor as well, feed it to any port on the FPGA. Read the port values and viola, you have the readings.