原理

眾所周知，三相電的鎖相環(huán)只需要進行Clark變換和Park變換得到dq分量，進行PI運算就可以輕松的完成鎖相，這里就不簡述Clark變換和Park變換了，網(wǎng)上一搜一大把資料，在此僅簡單闡述。

鎖相環(huán)的原理：

鎖相環(huán)就是講ABC三相通過clark變換和Park變換轉(zhuǎn)換成dq分量，通過dq來進行鎖相，鎖相環(huán)框圖如下：

clark變換：將abc 變換到 靜止 的αβ 坐標(biāo)系下。

設(shè)ABC三相電壓為：

通過U=x+ac+a^c變換合成矢量為

如圖所示，將它們投影到αβ軸上，有Clark transformation 3s−2s（僅考慮三相三線制情形，零序分量被忽略，詳細(xì)推導(dǎo)可參考陳伯時《電力拖動自動控制系統(tǒng)-運動控制系統(tǒng)》第三版 P263）。

Park變換：將abc 變換到 旋轉(zhuǎn) 的 dq 坐標(biāo)系下

clark變換到park變換

變換矩陣為

仿真

源碼

主要代碼如下：

//
// Included Files
//
#include <math.h>
#include "Interrupt.h"

/* ABC電壓值變量定義  */
FLOAT32 g_f32Ua;
FLOAT32 g_f32Ub;
FLOAT32 g_f32Uc;

typedef struct STRUCT_SPLL
{
    /* input data */
    FLOAT32 g_f32VoltD;
    FLOAT32 g_f32VoltQ;
    FLOAT32 g_f32Theta;
    /* output data */
    FLOAT32 g_f32SinWT;
    FLOAT32 g_f32CosWT;
    /* parameter */
    FLOAT32 g_f32VoltAlpha;
    FLOAT32 g_f32VoltBeta;
    PI_CONTROL_STRUCT PllLoop;
}ST_SPLL;
/* 鎖相環(huán)PI控制    */
#define PLL_MAX_OUT     2000
#define PLL_MIN_OUT    -2000

#define PLL_KP          48.0 * 2.0//12       // 0.3
#define PLL_KI          0.1 * 2.0//0.04    // 0.001




ST_SPLL g_stSpll = {0};

UINT16 g_u16VoltageIndex = 0;
UINT16 g_u16SendFlag = 0;
FLOAT32 g_f32VoltageSample[3] = {0};

void ISR_APP_ThreePhaseSPLL(ST_SPLL *t_spll, const FLOAT32 *VABC, UINT32 Ts);

//中斷頻率50k
#pragma CODE_SECTION(ISR_InterruptTask, ".TI.ramfunc");
__interrupt void ISR_InterruptTask(void)
{

	g_u16VoltageIndex++;
	if(g_u16VoltageIndex > 1000)
		g_u16VoltageIndex = 0;
	g_f32VoltageSample[0] = sinf(2 * M_PI * 100 / 1000 * g_u16VoltageIndex);//模擬輸出A相電壓,可由adc采樣值替換
	g_f32VoltageSample[1] = sinf(2 * M_PI * 100 / 1000 * g_u16VoltageIndex - 2*M_PI/3.0f);//模擬輸出B相電壓
	g_f32VoltageSample[2] = sinf(2 * M_PI * 100 / 1000 * g_u16VoltageIndex + 2*M_PI/3.0f);//模擬輸出C相電壓

	g_f32Ua = g_f32VoltageSample[0];
	g_f32Ub = g_f32VoltageSample[1];
	g_f32Uc = g_f32VoltageSample[2];
	ISR_APP_ThreePhaseSPLL(&g_stSpll, g_f32VoltageSample, 1000);//鎖相環(huán)函數(shù)

}


void APP_InitSpll(ST_SPLL *t_spll)
{
    t_spll->g_f32VoltD = 0;
    t_spll->g_f32VoltQ = 0;
    t_spll->g_f32Theta = 0;
    /* output data */
    t_spll->g_f32SinWT = 0;
    t_spll->g_f32CosWT = 0;
    /* parameter */
    t_spll->g_f32VoltAlpha = 0;
    t_spll->g_f32VoltBeta = 0;

    t_spll->PllLoop.m_u16CtrFlg = INCREMENTAL_CONTROL;		/* 增量式PI控制標(biāo)志  */

    t_spll->PllLoop.m_f32Ref = 0;							/* 給定                       */
    t_spll->PllLoop.m_f32Fed = 0;               			/* 反饋                       */

    t_spll->PllLoop.m_f32Err = 0;               			/* 誤差                       */
    t_spll->PllLoop.m_f32ErrPre = 0;            			/* 前拍誤差                */

    t_spll->PllLoop.m_f32Kp = PLL_KP;                		/* 比例參數(shù)                 */
    t_spll->PllLoop.m_f32Ki = PLL_KI;                		/* 積分參數(shù)                 */

    t_spll->PllLoop.m_f32Acc = 0;               			/* 積分累加               */
    t_spll->PllLoop.m_f32LoopOut = 0;           			/* 輸出                       */
    t_spll->PllLoop.m_f32KiMaxACC = PLL_MAX_OUT;          	/* 積分累加最大限幅  */
    t_spll->PllLoop.m_f32KiMinACC = PLL_MIN_OUT;          	/* 積分累加最小限幅  */
    t_spll->PllLoop.m_f32MaxOutput = PLL_MAX_OUT;         	/* 輸出最大限幅           */
    t_spll->PllLoop.m_f32MinOutput = PLL_MIN_OUT;         	/* 輸出最小限幅           */
}
#pragma CODE_SECTION(ISR_APP_ABC2ab, ".TI.ramfunc");
void ISR_APP_ThreePhaseSPLL(ST_SPLL *t_spll, const FLOAT32 *VABC, UINT32 Ts)
{

    FLOAT32 t_f32TempValue = 0;
    t_spll->g_f32VoltAlpha = 0.6666667f * (VABC[0]-(0.5f*VABC[1])-(0.5*VABC[2]));//Clark變換
    t_spll->g_f32VoltBeta = 0.6666667f*(((sqrtf(3)/2)*VABC[1])-((sqrtf(3)/2)*VABC[2]));

    #if 0                       //開環(huán)
    theta = 2 * M_PI * 50;
    #endif
	
	//Park變換
    t_spll->g_f32VoltD = t_spll->g_f32CosWT * t_spll->g_f32VoltAlpha + t_spll->g_f32SinWT * t_spll->g_f32VoltBeta;
    t_spll->g_f32VoltQ = -t_spll->g_f32SinWT * t_spll->g_f32VoltAlpha + t_spll->g_f32CosWT * t_spll->g_f32VoltBeta;
	
	//鎖相環(huán)環(huán)路計算
    t_spll->PllLoop.m_f32Ref = t_spll->g_f32VoltD;//0;
    t_spll->PllLoop.m_f32Fed = 0;//t_spll->g_f32VoltD;
    
    t_spll->PllLoop.m_f32Err = t_spll->PllLoop.m_f32Ref - t_spll->PllLoop.m_f32Fed;

    t_f32TempValue = t_spll->PllLoop.m_f32Ki * t_spll->PllLoop.m_f32Err;                              /* 積分計算  */
    t_f32TempValue += t_spll->PllLoop.m_f32Kp * (t_spll->PllLoop.m_f32Err - t_spll->PllLoop.m_f32ErrPre);          /* 比例計算  */
    t_spll->PllLoop.m_f32LoopOut += t_f32TempValue;/* 增量運算  */

    t_spll->PllLoop.m_f32ErrPre = t_spll->PllLoop.m_f32Err;

    if (t_spll->PllLoop.m_f32LoopOut > t_spll->PllLoop.m_f32MaxOutput)                                    /* 輸出限幅   */
    {
        t_spll->PllLoop.m_f32LoopOut = t_spll->PllLoop.m_f32MaxOutput;
    }

    if (t_spll->PllLoop.m_f32LoopOut < t_spll->PllLoop.m_f32MinOutput)
    {
        t_spll->PllLoop.m_f32LoopOut = t_spll->PllLoop.m_f32MinOutput;
    }


    t_spll->g_f32Theta += (t_spll->PllLoop.m_f32LoopOut / Ts);//環(huán)路輸出即為w，需要t積分

    if(t_spll->g_f32Theta > (2 * M_PI))
    {
        t_spll->g_f32Theta = t_spll->g_f32Theta - (2 * M_PI);
    }
    if(t_spll->g_f32Theta < 0)
    {
        t_spll->g_f32Theta = t_spll->g_f32Theta + (2 * M_PI);
    }
    t_spll->g_f32SinWT = sinf(t_spll->g_f32Theta);
    t_spll->g_f32CosWT = cosf(t_spll->g_f32Theta);
}

//
// End of File
//