TMS320F28035: SFRA in TMDSSOLAREXPKIT

I  amlearning to perform SFRA and at first I want to do it at TMDSSOLAREXPKIT in Close Loop. I receive the following result

Obviously I am doing something wrong. I did the following thing:

I use the 40kHz ISR so I declare:

#define SFRA_ISR_FREQ 40000
#define SFRA_FREQ_START 100
#define SFRA_FREQ_LENGTH 100

...

//SFRA Object Initialization
//Specify the injection amplitude
SFRA1.amplitude=_IQ26(0.01);

Then this is what I pass to SFRA:

duty_inv_pu=SFRA_IQ_INJECT(InvModIndex);
		PWMDRV_1phInv_unipolar(1,_IQ15(750),_IQ24mpy((InvSine<<9),duty_inv_pu));
	    SFRA_IQ_COLLECT(&duty_inv_pu,&inv_meas_cur_diff_inst);

where:

	
inv_meas_cur_lleg1_inst=(((int32) Ileg1_fb) <<12)-_IQ24(0.50); 
inv_meas_cur_lleg2_inst=(((int32) Ileg2_fb) <<12)-_IQ24(0.50); 

inv_meas_cur_diff_inst = (inv_meas_cur_lleg1_inst - inv_meas_cur_lleg2_inst)<<1; 

I put InvModIndex by hand and so it to 0.7 that gives around 22V at the output

Am I putting wrong variables to SFRA_IQ_COLLECT?

When I am doing Close loop model with PID then I receive decent plots, although I am aware that it also require more tuning
Close Loop: