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关于HV_SOLAR_DC_DC开发套件中MPPT算法启动的几个问题

各位好,我最近一段时间一直在研究TI公司出的HV_SOLAR_DC_DC开发套件,该开发套件用的是F28035芯片。在按照说明文档的要求顺利完成构建1和构建2的测试后,我在构建3的测试时遇到了MPPT算法不能启动的问题,几点疑问如下:

1.

依照说明手册UG_HV_SOLAR_DC_DC_Rev1操作,在BUILD 3 情况下,要启动

 MPPT,需要将下面这行CODE 忽略。

Start_DC_DC=1;//Start DC-DC MPPT provided LLC PWM is ON(This is checked in the 20kHz SECONDARY ISR)

我不明白为什么要注释掉这句话,因为从这个这段代码来看,前面的判断是板子的输入电压大于VPV_MIN(180v,在Solar_DC_DC-Settings.h里面设置)就可以自动使Start_DC_DC=1,而注释掉这句话的话就需要在程序运行后从ccs手动更改,而我给的太阳能电池板仿真器的参数完全满足大于180v这个下限电压,所以我不太明白注释这行代码的其他意义是什么?

if(Vp_fb_Avg >= VPV_MIN)
{

//Start_DC_DC=1;//Start DC-DC MPPT provided LLC PWM is ON(This is checked in the 20kHz SECONDARY ISR)

//***********************************************************************************
//To control the variable "Start_DC_DC" from CCS watch window and run the DC-DC code with external 12V bias (not using PR798 bias supply)
//COMMENT OUT the line above. This will allow code to run with MPPT off; Then the user will apply panel volt and start MPPT
//from CCS watch window by setting Start_DC_DC = 1
//************************************************************************************
}
else
{
Start_DC_DC = 0;//Do not start DC-DC MPPT
}

2.

在我开始运行程序后,我依照说明手册进入 real time mode 以及按下 Continuous Refresh buttons,此时Start_DC_DC = 0 ,inverter_connected = 1,LLC_PWM_ON=1,Operation_mode=0,这时我推测程序刚完成初始化,LLC的软启动也完成了,这时我在watch观察窗口更改Start_DC_DC = 1,inverter_connected =0,这时Operation_mode变为2,意味着有错误,输入电压也变为260v开路电压,LLC_PWM_ON变为0。

我查找了整个main程序发现能使Operation_mode变为2得只有下面这段程序

if(Operation_mode==1)//We also need to turn off LLC PWM to prevent OV condition at its output.

//But this cannot be done during start up since LLC has to be ON at that time.
//So we also check Operation_mode flag (Operation_mode=0=> startup mode,Operation_mode=1=>Run mode) before we turn off LLC PWM
{
EALLOW;
EPwm3Regs.TZFRC.bit.OST = 1;//Turn off LLC PWM when in RUN mode (Operation_mode=1)
EDIS;
LLC_PWM_ON = 0;
Operation_mode=2;//Go to restart mode, Operation_mode=2, and wait for restart command from inverter or the DC-DC GUI
}

但是进入这个程序的前提条件是Operation_mode==1,而整个过程Operation_mode变量从未变到过1,所以我有些不明白这个情况。

3.

关于GPIO_status这个变量的意义,通过读代码我发现这个变量只要不为0就无法启动mppt算法,原因如下

if(GPIO_status == 0)
{
Enable_mppt=1; //Enable MPPT.
Operation_mode=1;
A_Task_Ptr = &A1;
}

只有当它为0时mppt的使能变量才能为1。程序才能正常启动mppt,但是说明文档中从未提到过更改这一变量,我试着更改也失败了。

4

我尝试过用GUI来启动MPPT,但是也失败了,启动之后一开始输出电压为400v,但是会一直往下掉知道掉到和输入电压一样,GUI无法观测程序运行的具体情况所以我就猜测set键应该对应的是inverter_connected变量,operation mode status对应的是Operation_mode变量,那reset对应的是哪个变量呢?我的猜测对吗?