SPLL_1PH_SOGI_FLL

Introduction

Data Structures
struct	SPLL_1PH_SOGI_FLL_OSG_COEFF
	Defines the SPLL_1PH_SOGI_FLL_OSG_COEFF structure. More...
struct	SPLL_1PH_SOGI_FLL_LPF_COEFF
	Defines the SPLL_1PH_SOGI_FLL_LPF_COEFF structure. More...
struct	SPLL_1PH_SOGI_FLL
	Defines the Orthogonal Signal Generator SPLL_1PH_SOGI_FLL structure. More...

Functions
static void	SPLL_1PH_SOGI_FLL_reset (SPLL_1PH_SOGI_FLL *spll_obj)
	Resets internal data to zero,. More...
static void	SPLL_1PH_SOGI_FLL_coeff_calc (SPLL_1PH_SOGI_FLL *spll_obj)
	Calculates the SPLL_1PH_SOGI_FLL coefficients. More...
static void	SPLL_1PH_SOGI_FLL_config (SPLL_1PH_SOGI_FLL *spll_obj, float32_t acFreq, float32_t isrFrequency, float32_t lpf_b0, float32_t lpf_b1, float32_t k, float32_t gamma)
	Configures the SPLL_1PH_SOGI_FLL coefficients. More...
static void	SPLL_1PH_SOGI_FLL_run (SPLL_1PH_SOGI_FLL *spll_obj, float32_t acValue)
	Runs SPLL_1PH_SOGI_FLL module. More...

Typedefs
typedef float	float32_t
typedef long double	float64_t

Macros
#define	C2000_IEEE754_TYPES

Orthogonal Signal Generator SPLL with Frequency Locked Loop (SPLL_1PH_SOGI_FLL) Module

Introduction

The SPLL_1PH_SOGI_FLL API provides a set of functions that implements a software phase lock loop based on orthogonal signal generation using second order generalized integrators and frequency locked loop.

Orthogonal Signal Generator SPLL with FLL Model

This module follows the same basic structure as the SPLL_1PH_SOGI module and adds to the module a frequency adaptive feature through a frequency locked loop. The module implemented was first proposed by Rodriguez,P. ,Luna,A. , Candela,I. ,Teodorescu, R. , and Blaabjerg, F. in 'Grid Synchronization of Power Converters Using Multiple Second Order Generalized Integrators', In Proceedings of IEEE industrial Electronics Conference (IECON'08), November 2008, pp 755-760. An interesting relation was identified in the paper that the quadrature and the error component are in phase when the center frequency is greater than the actual and out of phase when it is lower than the actual. This feature is used to design a frequency locked loop as shown in figure below.

The value of k and γ are identified through simulation.

SOGI Phase Lock Loop with Frequency Locked Loop Structure Model

API Usage

The following is a sequence of steps that can be followed to use the SPLL_1PH_SOGI_FLL API library functions in an existing C program. For a set of code examples that illustrates the use of this library, see the examples in the Digial Power SDK.

Before you can using the library you must add the libraries directory path as a searchable directory in the project include options. This can be done by right-clicking on the project in the Project Explorer window, selecting "Properties". In the window that opens, navigate to "Build, C2000 Compiler, Include Options". In the include path
window, click on the green add directory path button on the right and enter the path to the Digital Power SDK libraries directory.

This allows CCS to search the entire directory for library files.

Once that is done you should follow these steps incorporate this library into your project:

1. Specify the include file(s)

   #include "spll_1ph_sogi_fll.h"

   
   
2. Create and add module structure to project source file

   SPLL_1PH_SOGI_FLL spll3;

   
   
3. Initialize module
   Note: The SPLL module is called in the interrupt service routine running at ISR_FREQUENCY by passing the pu value of the measured AC voltage. The sine and cosine values of the AC grid angle can then be obtained from the module's structure elements.
   

   SPLL_1PH_SOGI_FLL_reset(&spll3);
   SPLL_1PH_SOGI_FLL_config(&spll3, GRID_FREQ, ISR_FREQUENCY, (float32_t)(222.2862), (float32_t)(-222.034), (float32_t) 0.5, (float32_t) 20000);
   SPLL_1PH_SOGI_FLL_coeff_calc(&spll3);
   spll3.k=0.5;
   spll3.gamma=20000;

   
   
4. Using the module

   SPLL_1PH_SOGI_FLL_run(&spll3, ac_vol_sensed);
   spll_sine=spll3.sine;
   spll_cosine=spll3.cosine;

   
   Note: The functions are typically called in an interrupt source routine (ISR) which is called at the defined rate, ISR_FREQUENCY.

API Integration Information

There is only one module in this package, the APIs can be referenced at SPLL_1PH_SOGI_FLL. The module headers are located at spll_1ph_sogi_fll.h.

Macro Definition Documentation

C2000_IEEE754_TYPES

#define C2000_IEEE754_TYPES

Definition at line 48 of file spll_1ph_sogi_fll.h.

Typedef Documentation

float32_t

typedef float float32_t

Definition at line 53 of file spll_1ph_sogi_fll.h.

float64_t

typedef long double float64_t

Definition at line 54 of file spll_1ph_sogi_fll.h.

Function Documentation

SPLL_1PH_SOGI_FLL_reset()

static void SPLL_1PH_SOGI_FLL_reset ( SPLL_1PH_SOGI_FLL *  spll_obj )

inlinestatic

Resets internal data to zero,.

Parameters

*spll_obj

The SPLL_1PH_SOGI_FLL structure pointer

Returns

None

Definition at line 117 of file spll_1ph_sogi_fll.h.

SPLL_1PH_SOGI_FLL_coeff_calc()

static void SPLL_1PH_SOGI_FLL_coeff_calc ( SPLL_1PH_SOGI_FLL *  spll_obj )

inlinestatic

Calculates the SPLL_1PH_SOGI_FLL coefficients.

Parameters

*spll_obj

The SPLL_1PH_SOGI_FLL structure pointer

Returns

None

Definition at line 157 of file spll_1ph_sogi_fll.h.

SPLL_1PH_SOGI_FLL_config()

static void SPLL_1PH_SOGI_FLL_config ( SPLL_1PH_SOGI_FLL *  spll_obj, float32_t  acFreq, float32_t  isrFrequency, float32_t  lpf_b0, float32_t  lpf_b1, float32_t  k, float32_t  gamma  )

inlinestatic

Configures the SPLL_1PH_SOGI_FLL coefficients.

Parameters

*spll_obj	The SPLL_1PH_SOGI_FLL structure pointer
acFreq	Nominal AC frequency for the SPLL Module
isrFrequency	Nominal AC frequency for the SPLL Module
lpf_b0	B0 coefficient of LPF of SPLL
lpf_b1	B1 coefficient of LPF of SPLL
k	k parameter for FLL
gamma	gamma parameter for FLL

Returns

None

Definition at line 188 of file spll_1ph_sogi_fll.h.

SPLL_1PH_SOGI_FLL_run()

static void SPLL_1PH_SOGI_FLL_run ( SPLL_1PH_SOGI_FLL *  spll_obj, float32_t  acValue  )

inlinestatic

Runs SPLL_1PH_SOGI_FLL module.

Parameters

*spll_obj	The SPLL_1PH_SOGI_FLL structure pointer
acValue	AC grid voltage in per unit (pu)

Returns

None

Definition at line 214 of file spll_1ph_sogi_fll.h.