Other Parts Discussed in Thread: TIDA-01606, C2000WARE
I am working on custom inverter hardware trying to run the closed-loop current test with a load of 10 ohms per phase connected in a wye formation at the output.
For testing purposes, I have 200 VDC coming into the inverter.
Currently, I am seeing the vdInv_pu and the vqInv_pu clamp to 1.0 and -1.0 respectively.
Changing idRef_pu does nothing. Per phase current output readings are around 7Arms.
For testing purposes, I have 3 windings on my LEM sensors so I think the 21.0 A rms the controller is reading should be ok.
Here are my settings:
#define TINV_AC_FREQ_HZ ((float32_t)60) // 50 or 60 Hz per grid
#define TINV_VBUS_NOMINAL_VOLTS ((float32_t)800)
#define TINV_LI_INDUCTOR_VALUE ((float32_t)0.23*0.001)
#define TINV_LG_INDUCTOR_VALUE ((float32_t)1.3*0.001)
#define TINV_VGRID_MAX_SENSE_VOLTS ((float32_t)580)
#define TINV_VINV_MAX_SENSE_VOLTS TINV_VGRID_MAX_SENSE_VOLTS
#define TINV_VBUS_MAX_SENSE_VOLTS ((float32_t)875)
#define TINV_IINV_MAX_SENSE_AMPS ((float32_t)120)
#define TINV_IINV_TRIP_LIMIT_AMPS ((float32_t)130)
#define TINV_IGRID_MAX_SENSE_AMPS ((float32_t)120)
#define TINV_IGRID_TRIP_LIMIT_AMPS ((float32_t)130)
Here is my watch window:
For the scope capture:
Yellow is Phase A current. There is no grid or internal separation
Blue is Grid Voltage on Phase A
Pink is Differential Probe Phase A to Neutral
Green is Rogowski coil current clamp.
The signals don't seem like they would be an issue in causing the software to not allow me to adjust the current output.
Doing the math out, shows me that the control loop is calculating the vdInv_pu to be about 5.400 which is clamped to 1.0
gi_id_out | vGrid_dq0_pos.d | VGRID_MAX_SENSE_VOLTS | VBUS_MAX_SENSE_VOLTS | iInv_dq0_pos.q | DECOUPLING_CONST | LI_INDUCTOR_VALUE | IGRID_MAX_SENSE_AMPS | AC_FREQ_HZ | vBus_sensed_FilteredAndClamped_pu |
0.874100089 | -0.017847488 | 580 | 875 | -0.017847488 | 0.00019819 | 0.00023 | 120 | 60 | 0.31939131 |
vdInv_pu | |||||||||
5.400785547 |
Is there a reason this is putting the current to a maximum and not letting me adjust the current at all?