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diff --git a/Drivers/CMSIS/DSP/Include/dsp/controller_functions.h b/Drivers/CMSIS/DSP/Include/dsp/controller_functions.h new file mode 100644 index 0000000..7c08c24 --- /dev/null +++ b/Drivers/CMSIS/DSP/Include/dsp/controller_functions.h @@ -0,0 +1,791 @@ +/****************************************************************************** + * @file controller_functions.h + * @brief Public header file for CMSIS DSP Library + * @version V1.10.0 + * @date 08 July 2021 + * Target Processor: Cortex-M and Cortex-A cores + ******************************************************************************/ +/* + * Copyright (c) 2010-2020 Arm Limited or its affiliates. All rights reserved. + * + * SPDX-License-Identifier: Apache-2.0 + * + * Licensed under the Apache License, Version 2.0 (the License); you may + * not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an AS IS BASIS, WITHOUT + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + + +#ifndef _CONTROLLER_FUNCTIONS_H_ +#define _CONTROLLER_FUNCTIONS_H_ + +#include "arm_math_types.h" +#include "arm_math_memory.h" + +#include "dsp/none.h" +#include "dsp/utils.h" + +#ifdef __cplusplus +extern "C" +{ +#endif + + /** + * @brief Macros required for SINE and COSINE Controller functions + */ + +#define CONTROLLER_Q31_SHIFT (32 - 9) + /* 1.31(q31) Fixed value of 2/360 */ + /* -1 to +1 is divided into 360 values so total spacing is (2/360) */ +#define INPUT_SPACING 0xB60B61 + +/** + * @defgroup groupController Controller Functions + */ + + + /** + * @ingroup groupController + */ + + /** + * @addtogroup SinCos + * @{ + */ + +/** + * @brief Floating-point sin_cos function. + * @param[in] theta input value in degrees + * @param[out] pSinVal points to the processed sine output. + * @param[out] pCosVal points to the processed cos output. + */ + void arm_sin_cos_f32( + float32_t theta, + float32_t * pSinVal, + float32_t * pCosVal); + + + /** + * @brief Q31 sin_cos function. + * @param[in] theta scaled input value in degrees + * @param[out] pSinVal points to the processed sine output. + * @param[out] pCosVal points to the processed cosine output. + */ + void arm_sin_cos_q31( + q31_t theta, + q31_t * pSinVal, + q31_t * pCosVal); + + /** + * @} end of SinCos group + */ + + /** + * @ingroup groupController + */ + +/** + * @defgroup PID PID Motor Control + * + * A Proportional Integral Derivative (PID) controller is a generic feedback control + * loop mechanism widely used in industrial control systems. + * A PID controller is the most commonly used type of feedback controller. + * + * This set of functions implements (PID) controllers + * for Q15, Q31, and floating-point data types. The functions operate on a single sample + * of data and each call to the function returns a single processed value. + * <code>S</code> points to an instance of the PID control data structure. <code>in</code> + * is the input sample value. The functions return the output value. + * + * \par Algorithm: + * <pre> + * y[n] = y[n-1] + A0 * x[n] + A1 * x[n-1] + A2 * x[n-2] + * A0 = Kp + Ki + Kd + * A1 = (-Kp ) - (2 * Kd ) + * A2 = Kd + * </pre> + * + * \par + * where \c Kp is proportional constant, \c Ki is Integral constant and \c Kd is Derivative constant + * + * \par + * \image html PID.gif "Proportional Integral Derivative Controller" + * + * \par + * The PID controller calculates an "error" value as the difference between + * the measured output and the reference input. + * The controller attempts to minimize the error by adjusting the process control inputs. + * The proportional value determines the reaction to the current error, + * the integral value determines the reaction based on the sum of recent errors, + * and the derivative value determines the reaction based on the rate at which the error has been changing. + * + * \par Instance Structure + * The Gains A0, A1, A2 and state variables for a PID controller are stored together in an instance data structure. + * A separate instance structure must be defined for each PID Controller. + * There are separate instance structure declarations for each of the 3 supported data types. + * + * \par Reset Functions + * There is also an associated reset function for each data type which clears the state array. + * + * \par Initialization Functions + * There is also an associated initialization function for each data type. + * The initialization function performs the following operations: + * - Initializes the Gains A0, A1, A2 from Kp,Ki, Kd gains. + * - Zeros out the values in the state buffer. + * + * \par + * Instance structure cannot be placed into a const data section and it is recommended to use the initialization function. + * + * \par Fixed-Point Behavior + * Care must be taken when using the fixed-point versions of the PID Controller functions. + * In particular, the overflow and saturation behavior of the accumulator used in each function must be considered. + * Refer to the function specific documentation below for usage guidelines. + */ + + + /** + * @brief Instance structure for the Q15 PID Control. + */ + typedef struct + { + q15_t A0; /**< The derived gain, A0 = Kp + Ki + Kd . */ +#if !defined (ARM_MATH_DSP) + q15_t A1; /**< The derived gain A1 = -Kp - 2Kd */ + q15_t A2; /**< The derived gain A1 = Kd. */ +#else + q31_t A1; /**< The derived gain A1 = -Kp - 2Kd | Kd.*/ +#endif + q15_t state[3]; /**< The state array of length 3. */ + q15_t Kp; /**< The proportional gain. */ + q15_t Ki; /**< The integral gain. */ + q15_t Kd; /**< The derivative gain. */ + } arm_pid_instance_q15; + + /** + * @brief Instance structure for the Q31 PID Control. + */ + typedef struct + { + q31_t A0; /**< The derived gain, A0 = Kp + Ki + Kd . */ + q31_t A1; /**< The derived gain, A1 = -Kp - 2Kd. */ + q31_t A2; /**< The derived gain, A2 = Kd . */ + q31_t state[3]; /**< The state array of length 3. */ + q31_t Kp; /**< The proportional gain. */ + q31_t Ki; /**< The integral gain. */ + q31_t Kd; /**< The derivative gain. */ + } arm_pid_instance_q31; + + /** + * @brief Instance structure for the floating-point PID Control. + */ + typedef struct + { + float32_t A0; /**< The derived gain, A0 = Kp + Ki + Kd . */ + float32_t A1; /**< The derived gain, A1 = -Kp - 2Kd. */ + float32_t A2; /**< The derived gain, A2 = Kd . */ + float32_t state[3]; /**< The state array of length 3. */ + float32_t Kp; /**< The proportional gain. */ + float32_t Ki; /**< The integral gain. */ + float32_t Kd; /**< The derivative gain. */ + } arm_pid_instance_f32; + + + + /** + * @brief Initialization function for the floating-point PID Control. + * @param[in,out] S points to an instance of the PID structure. + * @param[in] resetStateFlag flag to reset the state. 0 = no change in state 1 = reset the state. + */ + void arm_pid_init_f32( + arm_pid_instance_f32 * S, + int32_t resetStateFlag); + + + /** + * @brief Reset function for the floating-point PID Control. + * @param[in,out] S is an instance of the floating-point PID Control structure + */ + void arm_pid_reset_f32( + arm_pid_instance_f32 * S); + + + /** + * @brief Initialization function for the Q31 PID Control. + * @param[in,out] S points to an instance of the Q15 PID structure. + * @param[in] resetStateFlag flag to reset the state. 0 = no change in state 1 = reset the state. + */ + void arm_pid_init_q31( + arm_pid_instance_q31 * S, + int32_t resetStateFlag); + + + /** + * @brief Reset function for the Q31 PID Control. + * @param[in,out] S points to an instance of the Q31 PID Control structure + */ + + void arm_pid_reset_q31( + arm_pid_instance_q31 * S); + + + /** + * @brief Initialization function for the Q15 PID Control. + * @param[in,out] S points to an instance of the Q15 PID structure. + * @param[in] resetStateFlag flag to reset the state. 0 = no change in state 1 = reset the state. + */ + void arm_pid_init_q15( + arm_pid_instance_q15 * S, + int32_t resetStateFlag); + + + /** + * @brief Reset function for the Q15 PID Control. + * @param[in,out] S points to an instance of the q15 PID Control structure + */ + void arm_pid_reset_q15( + arm_pid_instance_q15 * S); + + + + /** + * @addtogroup PID + * @{ + */ + + /** + * @brief Process function for the floating-point PID Control. + * @param[in,out] S is an instance of the floating-point PID Control structure + * @param[in] in input sample to process + * @return processed output sample. + */ + __STATIC_FORCEINLINE float32_t arm_pid_f32( + arm_pid_instance_f32 * S, + float32_t in) + { + float32_t out; + + /* y[n] = y[n-1] + A0 * x[n] + A1 * x[n-1] + A2 * x[n-2] */ + out = (S->A0 * in) + + (S->A1 * S->state[0]) + (S->A2 * S->state[1]) + (S->state[2]); + + /* Update state */ + S->state[1] = S->state[0]; + S->state[0] = in; + S->state[2] = out; + + /* return to application */ + return (out); + + } + +/** + @brief Process function for the Q31 PID Control. + @param[in,out] S points to an instance of the Q31 PID Control structure + @param[in] in input sample to process + @return processed output sample. + + \par Scaling and Overflow Behavior + The function is implemented using an internal 64-bit accumulator. + The accumulator has a 2.62 format and maintains full precision of the intermediate multiplication results but provides only a single guard bit. + Thus, if the accumulator result overflows it wraps around rather than clip. + In order to avoid overflows completely the input signal must be scaled down by 2 bits as there are four additions. + After all multiply-accumulates are performed, the 2.62 accumulator is truncated to 1.32 format and then saturated to 1.31 format. + */ +__STATIC_FORCEINLINE q31_t arm_pid_q31( + arm_pid_instance_q31 * S, + q31_t in) + { + q63_t acc; + q31_t out; + + /* acc = A0 * x[n] */ + acc = (q63_t) S->A0 * in; + + /* acc += A1 * x[n-1] */ + acc += (q63_t) S->A1 * S->state[0]; + + /* acc += A2 * x[n-2] */ + acc += (q63_t) S->A2 * S->state[1]; + + /* convert output to 1.31 format to add y[n-1] */ + out = (q31_t) (acc >> 31U); + + /* out += y[n-1] */ + out += S->state[2]; + + /* Update state */ + S->state[1] = S->state[0]; + S->state[0] = in; + S->state[2] = out; + + /* return to application */ + return (out); + } + + +/** + @brief Process function for the Q15 PID Control. + @param[in,out] S points to an instance of the Q15 PID Control structure + @param[in] in input sample to process + @return processed output sample. + + \par Scaling and Overflow Behavior + The function is implemented using a 64-bit internal accumulator. + Both Gains and state variables are represented in 1.15 format and multiplications yield a 2.30 result. + The 2.30 intermediate results are accumulated in a 64-bit accumulator in 34.30 format. + There is no risk of internal overflow with this approach and the full precision of intermediate multiplications is preserved. + After all additions have been performed, the accumulator is truncated to 34.15 format by discarding low 15 bits. + Lastly, the accumulator is saturated to yield a result in 1.15 format. + */ +__STATIC_FORCEINLINE q15_t arm_pid_q15( + arm_pid_instance_q15 * S, + q15_t in) + { + q63_t acc; + q15_t out; + +#if defined (ARM_MATH_DSP) + /* Implementation of PID controller */ + + /* acc = A0 * x[n] */ + acc = (q31_t) __SMUAD((uint32_t)S->A0, (uint32_t)in); + + /* acc += A1 * x[n-1] + A2 * x[n-2] */ + acc = (q63_t)__SMLALD((uint32_t)S->A1, (uint32_t)read_q15x2 (S->state), (uint64_t)acc); +#else + /* acc = A0 * x[n] */ + acc = ((q31_t) S->A0) * in; + + /* acc += A1 * x[n-1] + A2 * x[n-2] */ + acc += (q31_t) S->A1 * S->state[0]; + acc += (q31_t) S->A2 * S->state[1]; +#endif + + /* acc += y[n-1] */ + acc += (q31_t) S->state[2] << 15; + + /* saturate the output */ + out = (q15_t) (__SSAT((q31_t)(acc >> 15), 16)); + + /* Update state */ + S->state[1] = S->state[0]; + S->state[0] = in; + S->state[2] = out; + + /* return to application */ + return (out); + } + + /** + * @} end of PID group + */ + + /** + * @ingroup groupController + */ + + /** + * @defgroup park Vector Park Transform + * + * Forward Park transform converts the input two-coordinate vector to flux and torque components. + * The Park transform can be used to realize the transformation of the <code>Ialpha</code> and the <code>Ibeta</code> currents + * from the stationary to the moving reference frame and control the spatial relationship between + * the stator vector current and rotor flux vector. + * If we consider the d axis aligned with the rotor flux, the diagram below shows the + * current vector and the relationship from the two reference frames: + * \image html park.gif "Stator current space vector and its component in (a,b) and in the d,q rotating reference frame" + * + * The function operates on a single sample of data and each call to the function returns the processed output. + * The library provides separate functions for Q31 and floating-point data types. + * \par Algorithm + * \image html parkFormula.gif + * where <code>Ialpha</code> and <code>Ibeta</code> are the stator vector components, + * <code>pId</code> and <code>pIq</code> are rotor vector components and <code>cosVal</code> and <code>sinVal</code> are the + * cosine and sine values of theta (rotor flux position). + * \par Fixed-Point Behavior + * Care must be taken when using the Q31 version of the Park transform. + * In particular, the overflow and saturation behavior of the accumulator used must be considered. + * Refer to the function specific documentation below for usage guidelines. + */ + + /** + * @addtogroup park + * @{ + */ + + /** + * @brief Floating-point Park transform + * @param[in] Ialpha input two-phase vector coordinate alpha + * @param[in] Ibeta input two-phase vector coordinate beta + * @param[out] pId points to output rotor reference frame d + * @param[out] pIq points to output rotor reference frame q + * @param[in] sinVal sine value of rotation angle theta + * @param[in] cosVal cosine value of rotation angle theta + * @return none + * + * The function implements the forward Park transform. + * + */ + __STATIC_FORCEINLINE void arm_park_f32( + float32_t Ialpha, + float32_t Ibeta, + float32_t * pId, + float32_t * pIq, + float32_t sinVal, + float32_t cosVal) + { + /* Calculate pId using the equation, pId = Ialpha * cosVal + Ibeta * sinVal */ + *pId = Ialpha * cosVal + Ibeta * sinVal; + + /* Calculate pIq using the equation, pIq = - Ialpha * sinVal + Ibeta * cosVal */ + *pIq = -Ialpha * sinVal + Ibeta * cosVal; + } + + +/** + @brief Park transform for Q31 version + @param[in] Ialpha input two-phase vector coordinate alpha + @param[in] Ibeta input two-phase vector coordinate beta + @param[out] pId points to output rotor reference frame d + @param[out] pIq points to output rotor reference frame q + @param[in] sinVal sine value of rotation angle theta + @param[in] cosVal cosine value of rotation angle theta + @return none + + \par Scaling and Overflow Behavior + The function is implemented using an internal 32-bit accumulator. + The accumulator maintains 1.31 format by truncating lower 31 bits of the intermediate multiplication in 2.62 format. + There is saturation on the addition and subtraction, hence there is no risk of overflow. + */ +__STATIC_FORCEINLINE void arm_park_q31( + q31_t Ialpha, + q31_t Ibeta, + q31_t * pId, + q31_t * pIq, + q31_t sinVal, + q31_t cosVal) + { + q31_t product1, product2; /* Temporary variables used to store intermediate results */ + q31_t product3, product4; /* Temporary variables used to store intermediate results */ + + /* Intermediate product is calculated by (Ialpha * cosVal) */ + product1 = (q31_t) (((q63_t) (Ialpha) * (cosVal)) >> 31); + + /* Intermediate product is calculated by (Ibeta * sinVal) */ + product2 = (q31_t) (((q63_t) (Ibeta) * (sinVal)) >> 31); + + + /* Intermediate product is calculated by (Ialpha * sinVal) */ + product3 = (q31_t) (((q63_t) (Ialpha) * (sinVal)) >> 31); + + /* Intermediate product is calculated by (Ibeta * cosVal) */ + product4 = (q31_t) (((q63_t) (Ibeta) * (cosVal)) >> 31); + + /* Calculate pId by adding the two intermediate products 1 and 2 */ + *pId = __QADD(product1, product2); + + /* Calculate pIq by subtracting the two intermediate products 3 from 4 */ + *pIq = __QSUB(product4, product3); + } + + /** + * @} end of park group + */ + + + /** + * @ingroup groupController + */ + + /** + * @defgroup inv_park Vector Inverse Park transform + * Inverse Park transform converts the input flux and torque components to two-coordinate vector. + * + * The function operates on a single sample of data and each call to the function returns the processed output. + * The library provides separate functions for Q31 and floating-point data types. + * \par Algorithm + * \image html parkInvFormula.gif + * where <code>pIalpha</code> and <code>pIbeta</code> are the stator vector components, + * <code>Id</code> and <code>Iq</code> are rotor vector components and <code>cosVal</code> and <code>sinVal</code> are the + * cosine and sine values of theta (rotor flux position). + * \par Fixed-Point Behavior + * Care must be taken when using the Q31 version of the Park transform. + * In particular, the overflow and saturation behavior of the accumulator used must be considered. + * Refer to the function specific documentation below for usage guidelines. + */ + + /** + * @addtogroup inv_park + * @{ + */ + + /** + * @brief Floating-point Inverse Park transform + * @param[in] Id input coordinate of rotor reference frame d + * @param[in] Iq input coordinate of rotor reference frame q + * @param[out] pIalpha points to output two-phase orthogonal vector axis alpha + * @param[out] pIbeta points to output two-phase orthogonal vector axis beta + * @param[in] sinVal sine value of rotation angle theta + * @param[in] cosVal cosine value of rotation angle theta + * @return none + */ + __STATIC_FORCEINLINE void arm_inv_park_f32( + float32_t Id, + float32_t Iq, + float32_t * pIalpha, + float32_t * pIbeta, + float32_t sinVal, + float32_t cosVal) + { + /* Calculate pIalpha using the equation, pIalpha = Id * cosVal - Iq * sinVal */ + *pIalpha = Id * cosVal - Iq * sinVal; + + /* Calculate pIbeta using the equation, pIbeta = Id * sinVal + Iq * cosVal */ + *pIbeta = Id * sinVal + Iq * cosVal; + } + + +/** + @brief Inverse Park transform for Q31 version + @param[in] Id input coordinate of rotor reference frame d + @param[in] Iq input coordinate of rotor reference frame q + @param[out] pIalpha points to output two-phase orthogonal vector axis alpha + @param[out] pIbeta points to output two-phase orthogonal vector axis beta + @param[in] sinVal sine value of rotation angle theta + @param[in] cosVal cosine value of rotation angle theta + @return none + + @par Scaling and Overflow Behavior + The function is implemented using an internal 32-bit accumulator. + The accumulator maintains 1.31 format by truncating lower 31 bits of the intermediate multiplication in 2.62 format. + There is saturation on the addition, hence there is no risk of overflow. + */ +__STATIC_FORCEINLINE void arm_inv_park_q31( + q31_t Id, + q31_t Iq, + q31_t * pIalpha, + q31_t * pIbeta, + q31_t sinVal, + q31_t cosVal) + { + q31_t product1, product2; /* Temporary variables used to store intermediate results */ + q31_t product3, product4; /* Temporary variables used to store intermediate results */ + + /* Intermediate product is calculated by (Id * cosVal) */ + product1 = (q31_t) (((q63_t) (Id) * (cosVal)) >> 31); + + /* Intermediate product is calculated by (Iq * sinVal) */ + product2 = (q31_t) (((q63_t) (Iq) * (sinVal)) >> 31); + + + /* Intermediate product is calculated by (Id * sinVal) */ + product3 = (q31_t) (((q63_t) (Id) * (sinVal)) >> 31); + + /* Intermediate product is calculated by (Iq * cosVal) */ + product4 = (q31_t) (((q63_t) (Iq) * (cosVal)) >> 31); + + /* Calculate pIalpha by using the two intermediate products 1 and 2 */ + *pIalpha = __QSUB(product1, product2); + + /* Calculate pIbeta by using the two intermediate products 3 and 4 */ + *pIbeta = __QADD(product4, product3); + } + + /** + * @} end of Inverse park group + */ + +/** + * @ingroup groupController + */ + + /** + * @defgroup clarke Vector Clarke Transform + * Forward Clarke transform converts the instantaneous stator phases into a two-coordinate time invariant vector. + * Generally the Clarke transform uses three-phase currents <code>Ia, Ib and Ic</code> to calculate currents + * in the two-phase orthogonal stator axis <code>Ialpha</code> and <code>Ibeta</code>. + * When <code>Ialpha</code> is superposed with <code>Ia</code> as shown in the figure below + * \image html clarke.gif Stator current space vector and its components in (a,b). + * and <code>Ia + Ib + Ic = 0</code>, in this condition <code>Ialpha</code> and <code>Ibeta</code> + * can be calculated using only <code>Ia</code> and <code>Ib</code>. + * + * The function operates on a single sample of data and each call to the function returns the processed output. + * The library provides separate functions for Q31 and floating-point data types. + * \par Algorithm + * \image html clarkeFormula.gif + * where <code>Ia</code> and <code>Ib</code> are the instantaneous stator phases and + * <code>pIalpha</code> and <code>pIbeta</code> are the two coordinates of time invariant vector. + * \par Fixed-Point Behavior + * Care must be taken when using the Q31 version of the Clarke transform. + * In particular, the overflow and saturation behavior of the accumulator used must be considered. + * Refer to the function specific documentation below for usage guidelines. + */ + + /** + * @addtogroup clarke + * @{ + */ + + /** + * + * @brief Floating-point Clarke transform + * @param[in] Ia input three-phase coordinate <code>a</code> + * @param[in] Ib input three-phase coordinate <code>b</code> + * @param[out] pIalpha points to output two-phase orthogonal vector axis alpha + * @param[out] pIbeta points to output two-phase orthogonal vector axis beta + * @return none + */ + __STATIC_FORCEINLINE void arm_clarke_f32( + float32_t Ia, + float32_t Ib, + float32_t * pIalpha, + float32_t * pIbeta) + { + /* Calculate pIalpha using the equation, pIalpha = Ia */ + *pIalpha = Ia; + + /* Calculate pIbeta using the equation, pIbeta = (1/sqrt(3)) * Ia + (2/sqrt(3)) * Ib */ + *pIbeta = (0.57735026919f * Ia + 1.15470053838f * Ib); + } + + +/** + @brief Clarke transform for Q31 version + @param[in] Ia input three-phase coordinate <code>a</code> + @param[in] Ib input three-phase coordinate <code>b</code> + @param[out] pIalpha points to output two-phase orthogonal vector axis alpha + @param[out] pIbeta points to output two-phase orthogonal vector axis beta + @return none + + \par Scaling and Overflow Behavior + The function is implemented using an internal 32-bit accumulator. + The accumulator maintains 1.31 format by truncating lower 31 bits of the intermediate multiplication in 2.62 format. + There is saturation on the addition, hence there is no risk of overflow. + */ +__STATIC_FORCEINLINE void arm_clarke_q31( + q31_t Ia, + q31_t Ib, + q31_t * pIalpha, + q31_t * pIbeta) + { + q31_t product1, product2; /* Temporary variables used to store intermediate results */ + + /* Calculating pIalpha from Ia by equation pIalpha = Ia */ + *pIalpha = Ia; + + /* Intermediate product is calculated by (1/(sqrt(3)) * Ia) */ + product1 = (q31_t) (((q63_t) Ia * 0x24F34E8B) >> 30); + + /* Intermediate product is calculated by (2/sqrt(3) * Ib) */ + product2 = (q31_t) (((q63_t) Ib * 0x49E69D16) >> 30); + + /* pIbeta is calculated by adding the intermediate products */ + *pIbeta = __QADD(product1, product2); + } + + /** + * @} end of clarke group + */ + + + /** + * @ingroup groupController + */ + + /** + * @defgroup inv_clarke Vector Inverse Clarke Transform + * Inverse Clarke transform converts the two-coordinate time invariant vector into instantaneous stator phases. + * + * The function operates on a single sample of data and each call to the function returns the processed output. + * The library provides separate functions for Q31 and floating-point data types. + * \par Algorithm + * \image html clarkeInvFormula.gif + * where <code>pIa</code> and <code>pIb</code> are the instantaneous stator phases and + * <code>Ialpha</code> and <code>Ibeta</code> are the two coordinates of time invariant vector. + * \par Fixed-Point Behavior + * Care must be taken when using the Q31 version of the Clarke transform. + * In particular, the overflow and saturation behavior of the accumulator used must be considered. + * Refer to the function specific documentation below for usage guidelines. + */ + + /** + * @addtogroup inv_clarke + * @{ + */ + + /** + * @brief Floating-point Inverse Clarke transform + * @param[in] Ialpha input two-phase orthogonal vector axis alpha + * @param[in] Ibeta input two-phase orthogonal vector axis beta + * @param[out] pIa points to output three-phase coordinate <code>a</code> + * @param[out] pIb points to output three-phase coordinate <code>b</code> + * @return none + */ + __STATIC_FORCEINLINE void arm_inv_clarke_f32( + float32_t Ialpha, + float32_t Ibeta, + float32_t * pIa, + float32_t * pIb) + { + /* Calculating pIa from Ialpha by equation pIa = Ialpha */ + *pIa = Ialpha; + + /* Calculating pIb from Ialpha and Ibeta by equation pIb = -(1/2) * Ialpha + (sqrt(3)/2) * Ibeta */ + *pIb = -0.5f * Ialpha + 0.8660254039f * Ibeta; + } + + +/** + @brief Inverse Clarke transform for Q31 version + @param[in] Ialpha input two-phase orthogonal vector axis alpha + @param[in] Ibeta input two-phase orthogonal vector axis beta + @param[out] pIa points to output three-phase coordinate <code>a</code> + @param[out] pIb points to output three-phase coordinate <code>b</code> + @return none + + \par Scaling and Overflow Behavior + The function is implemented using an internal 32-bit accumulator. + The accumulator maintains 1.31 format by truncating lower 31 bits of the intermediate multiplication in 2.62 format. + There is saturation on the subtraction, hence there is no risk of overflow. + */ +__STATIC_FORCEINLINE void arm_inv_clarke_q31( + q31_t Ialpha, + q31_t Ibeta, + q31_t * pIa, + q31_t * pIb) + { + q31_t product1, product2; /* Temporary variables used to store intermediate results */ + + /* Calculating pIa from Ialpha by equation pIa = Ialpha */ + *pIa = Ialpha; + + /* Intermediate product is calculated by (1/(2*sqrt(3)) * Ia) */ + product1 = (q31_t) (((q63_t) (Ialpha) * (0x40000000)) >> 31); + + /* Intermediate product is calculated by (1/sqrt(3) * pIb) */ + product2 = (q31_t) (((q63_t) (Ibeta) * (0x6ED9EBA1)) >> 31); + + /* pIb is calculated by subtracting the products */ + *pIb = __QSUB(product2, product1); + } + + /** + * @} end of inv_clarke group + */ + + + + +#ifdef __cplusplus +} +#endif + +#endif /* ifndef _CONTROLLER_FUNCTIONS_H_ */ |