Kp adjustment#

void uz_CurrentControl_adjust_Kp(uz_CurrentControl_t *self, uz_3ph_dq_t i_reference_Ampere, uz_3ph_dq_t i_actual_Ampere, float BO_factor)#

Function to adjust the Kp parameter of the PI-Controllers during runtime based on nonlinear flux-maps.

Parameters:

  • self – uz_CurrentControl_t instance

  • i_reference_Ampere – uz_dq_t struct for reference dq-currents in Ampere

  • i_actual_Ampere – uz_dq_t struct for measured dq-currents in Ampere

  • BO_factor – factor for magnitude optimum

Example#

Listing 83 Example function call to calculate kp adjustment parameters.#
 1int main(void) {
 2  struct uz_CurrentControl_config config = {
 3  config_iq.samplingTime_sec = 0.00001f
 4  };  //only this parameter is needed
 5  uz_CurrentControl_t* instance = uz_CurrentControl_init(config);
 6  struct uz_3ph_dq_t i_actual_Ampere = {.d = 0.8f, .q = 0.8f, .zero = 0.0f};
 7  struct uz_3ph_dq_t i_reference_Ampere = {.d = 1.0f, .q = 1.0f, .zero = 0.0f};
 8  struct uz_3ph_dq_t flux_approx_real = {.d = 0.00040f, .q = 0.0019f, .zero = 0.0f};
 9  struct uz_3ph_dq_t flux_approx_reference = {.d = 0.00045f, .q = 0.002f, .zero = 0.0f};
10  float factor = 2.0f //Magnitude optimum factor
11  uz_CurrentControl_set_flux_approx(instance,flux_approx_real,flux_approx_reference);
12  uz_CurrentControl_adjust_Kp(i_actual_Ampere, i_reference_Ampere, factor);
13  }

Description#

Calculates the new adjusted values of the kp parameters following the functions described in [[1], p. 913] or [[2], p. 102]. It has to be used in conjunction with Set flux approximation.

\[\begin{split}\overline{L}_{dd} = \frac{\psi_{d}(i_{d}^*,i_{q})-\psi_{d}(i_{d},i_{q})}{i_{d}^*-i_{d}} \\ \overline{L}_{qq} = \frac{\psi_{q}(i_{d},i_{q}^*)-\psi_{q}(i_{d},i_{q})}{i_{q}^*-i_{q}}\end{split}\]

Then the new Kp parameters can be calculated:

\[K_{p,d} = \frac{\overline{L}_{dd}}{2\tau_\sigma} \qquad \qquad \qquad K_{p,q} = \frac{\overline{L}{qq}}{2\tau_\sigma}\]

If the flag Kp_adjustment_flag is set to true in the uz_CurrentControl_config, the calculated \(K_{p,d}\) and \(K_{p,q}\) are automatically written to the pi controllers. If false, no adjustment of \(K_{p,d}\) and \(K_{p,q}\) is done.