Three-phase neutral-point-clamped power conversion device
First Claim
1. A three-phase neutral point clamped power conversion apparatus comprising a control circuit which comprises:
- a first three-phase to two-phase converter configured to convert a three-phase detected current to a two-phase detected current of a d-axis detected current and a q-axis detected current;
a current control section configured to calculate a two-phase command voltage with a current control function of performing a PI control in accordance with a deviation between a d-axis command current and the d-axis detected current and a deviation between a q-axis command current and the q-axis detected current;
a two-phase to three-phase converter configured to convert the two-phase command voltage to a three-phase command voltage;
a neutral point potential control section configured to calculate a neutral point control compensation quantity in accordance with a deviation between a positive side dc voltage and a negative side dc voltage, and to add the neutral point control compensation quantity to the three-phase command voltage thereby to calculate a corrected command voltage;
a limiter configured to output a limiter processed command voltage by limiting the corrected command voltage to or below a threshold value; and
a second three-phase to two-phase converter configured to output a feedback quantity by three-phase to two-phase conversion of the limiter processed command voltage;
the current control section being configured to perform an integral control in accordance with the feedback quantity resulting from the three-phase to the two-phase conversion, the deviation between the d-axis command current and the d-axis detected current and the deviation between the q-axis command current and the q-axis detected current,wherein the limiter is configured to output the limiter processed command voltage to a processor to perform pulse width modulation processing, andwherein the limiter is configured to receive the corrected command voltage after a neutral point potential compensation quantity is added but before the processor performs the pulse width modulation processing.
1 Assignment
0 Petitions
Accused Products
Abstract
Current control section 2 performs PI control based on deviation between d-axis command current Id_cmd and d-axis detected current Id_det and deviation between q-axis command current Iq_cmd and q-axis detected current Iq_det. Neutral point potential control section 4 calculates corrected command voltage V_cmd′ by addition of neutral point control compensation quantity V_cmp to three-phase command voltage V_cmd. Limiter LMT3 outputs limiter processed command voltage V_cmd″ by liming the output of corrected command voltage V_cmd′. Three-phase to two-phase converter 5 outputs feedback quantities Vd_back, Vq_back by three-phase to two-phase conversion of the limiter processed command voltage V_cmd″. Current control section 2 performs integral control in accordance with quantities resulting from addition of the feedback quantities Vd_back, Vq_back to the deviations. Accordingly, the three-phase neutral point clamed power conversion apparatus performing the PWM control suppresses interference between the current control and the neutral point potential control.
16 Citations
18 Claims
-
1. A three-phase neutral point clamped power conversion apparatus comprising a control circuit which comprises:
-
a first three-phase to two-phase converter configured to convert a three-phase detected current to a two-phase detected current of a d-axis detected current and a q-axis detected current; a current control section configured to calculate a two-phase command voltage with a current control function of performing a PI control in accordance with a deviation between a d-axis command current and the d-axis detected current and a deviation between a q-axis command current and the q-axis detected current; a two-phase to three-phase converter configured to convert the two-phase command voltage to a three-phase command voltage; a neutral point potential control section configured to calculate a neutral point control compensation quantity in accordance with a deviation between a positive side dc voltage and a negative side dc voltage, and to add the neutral point control compensation quantity to the three-phase command voltage thereby to calculate a corrected command voltage; a limiter configured to output a limiter processed command voltage by limiting the corrected command voltage to or below a threshold value; and a second three-phase to two-phase converter configured to output a feedback quantity by three-phase to two-phase conversion of the limiter processed command voltage; the current control section being configured to perform an integral control in accordance with the feedback quantity resulting from the three-phase to the two-phase conversion, the deviation between the d-axis command current and the d-axis detected current and the deviation between the q-axis command current and the q-axis detected current, wherein the limiter is configured to output the limiter processed command voltage to a processor to perform pulse width modulation processing, and wherein the limiter is configured to receive the corrected command voltage after a neutral point potential compensation quantity is added but before the processor performs the pulse width modulation processing. - View Dependent Claims (2, 3, 4, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18)
-
-
5. A three-phase neutral point clamped power conversion process comprising:
-
a first three-phase to two-phase converting step of converting a three-phase detected current to a two-phase detected current of a d-axis detected current and a q-axis detected current; a current control step of calculating a two-phase command voltage with a current control function of performing a PI control in accordance with a deviation between a d-axis command current and the d-axis detected current and a deviation between a q-axis command current and the q-axis detected current; a two-phase to three-phase converting step of converting the two-phase command voltage to a three-phase command voltage; a neutral point potential control step of calculating a neutral point control compensation quantity in accordance with a deviation between a positive side dc voltage and a negative side dc voltage, and adding the neutral point control compensation quantity to the three-phase command voltage thereby to calculate a corrected command voltage; a limiting step of outputting a limiter processed command voltage by limiting, by a limiter, the corrected command voltage to or below a threshold value; and a second three-phase to two-phase converting step of outputting a feedback quantity by three-phase to two-phase conversion of the limiter processed command voltage; wherein, in the current control step, an integral control is performed in accordance with the feedback quantity resulting from the three-phase to the two-phase conversion, the deviation between the d-axis command current and the d-axis detected current and the deviation between the q-axis command current and the q-axis detected current, wherein the limiter is configured to output the limiter processed command voltage to a processor to perform pulse width modulation processing, and wherein the limiter is configured to receive the corrected command voltage after a neutral point potential compensation quantity is added but before the processor performs the pulse width modulation processing.
-
-
13. A three-phase neutral point clamped power conversion apparatus comprising a control circuit which comprises:
-
a first three-phase to two-phase converter configured to convert a three-phase detected current to a two-phase detected current of a d-axis detected current and a q-axis detected current; a current control section configured to calculate a two-phase command voltage with a current control function of performing a PI control in accordance with a deviation between a d-axis command current and the d-axis detected current and a deviation between a q-axis command current and the q-axis detected current; a two-phase to three-phase converter configured to convert the two-phase command voltage to a three-phase command voltage; a neutral point potential control section configured to calculate a neutral point control compensation quantity in accordance with a deviation between a positive side dc voltage and a negative side dc voltage, and to add the neutral point control compensation quantity to the three-phase command voltage thereby to calculate a three-phase corrected command voltage; a limiter configured to output a limiter processed three-phase command voltage by limiting the three-phase corrected command voltage to or below a threshold value; and a second three-phase to two-phase converter configured to output a feedback quantity by three-phase to two-phase conversion of the limiter processed three-phase command voltage; the current control section including a proportional control section to perform a proportional control based on a control deviation which is one of the deviation between the d-axis command current and the d-axis detected current or the deviation between the q-axis command current and the q-axis detected current without using the feedback quantity, and an integral control section to perform the integral control based on the control deviation by using the feedback quantity, wherein the limiter is configured to output the limiter processed three-phase command voltage to a processor to perform pulse width modulation processing, and wherein the limiter is configured to receive the three-phase corrected command voltage after a neutral point potential compensation quantity is added but before the processor performs the pulse width modulation processing.
-
Specification