3 Firmware description

PFC for ST7MC Starter Kit

10/20

Figure 8 shows the PFC_TON_ADJUST routine.

Figure 8.

PFC_TON_ADJUST

3.2

PFC software description

This paragraph contains a description of the part of the software related to the PFC. The

complete explanation of the software is beyond this AN. For a more detailed explanation of the

motor control software library please refer to the application note AN1904.

The modules related to PFC are the following:

●

Pfc.c

●

Pwmart.c (Partially)

●

Timer.c

The file Pfc.h contains some parameters that can be customized by the user according the

application.

At the beginning of the main module (main.c) there is the initialization of the PFC variables and

timer parameters.

PFC_Init();

PFC_TIMER_Init();

SetBit(TBCR2,TBCR2_OC1E);

Then in the main loop the only two tasks performed are the acquisition of the Bus voltage Vout

Vout > Vout400

PFC Running

PWM Start

Error = Kp * (Vout400 - Vout)

Error > 3

No

Yes

Yes

Error = 3

Ton = Ton + Error

Ton > MAX_TON

Yes

Ton = MAX_TON

Number Of Ton Increase++

Number Of Ton Increase

> MAXTONINCREASE

Yes

PFC TOTONINCREASE

Stop PWM

Error = Kp * (Vout - Vout400)

Error > 3

Yes

Error = 3

Yes

Error > Ton

Ton = MIN_TON

Ton = Ton - Error

Ton < MIN_TON

Yes

Ton = MIN_TON