US 12,237,785 B2
Electrical power conversion apparatus
Ryo Shinohara, Tokyo (JP)
Assigned to Mitsubishi Electric Corporation, Tokyo (JP)
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
Filed on Apr. 20, 2023, as Appl. No. 18/303,714.
Claims priority of application No. 2022-089371 (JP), filed on Jun. 1, 2022.
Prior Publication US 2023/0396198 A1, Dec. 7, 2023
Int. Cl. H02P 21/16 (2016.01); H02P 21/22 (2016.01); H02P 27/12 (2006.01)
CPC H02P 21/16 (2016.02) [H02P 21/22 (2016.02); H02P 27/12 (2013.01)] 21 Claims
OG exemplary drawing
 
1. An electrical power conversion apparatus, comprising:
a semiconductor switching element for converting electric power through switching operations thereof;
a cooling device for cooling said semiconductor switching element;
a control device for controlling said semiconductor switching element;
a temperature detector for detecting a temperature of said semiconductor switching element; and
an electric current detector for detecting an electric current flowing through said semiconductor switching element, wherein
the control device comprises:
a semiconductor-switching-element loss calculator for calculating a loss of said semiconductor switching element on a basis of an electric current detection value obtained by the electric current detector;
a temperature-detection change-rate estimation-calculation device for estimating a change rate of a temperature detection value obtained by the temperature detector, on a basis of a switching-element loss calculation value of the semiconductor-switching-element loss calculator;
a temperature-detection change-rate calculation device for calculating a temperature-detection change-rate from a temperature detection value obtained by the temperature detector; and
a heat generation abnormality-state determination device for estimating a heat generation abnormality-state of said semiconductor switching element by comparing a temperature-detection change-rate estimation value obtained by the temperature-detection change-rate estimation-calculation device with a temperature-detection change-rate calculation value obtained by the temperature-detection change-rate calculation device.