US 11,843,287 B2
Motor thermal protection device and operation method thereof
Zhangji Zhou, Shanghai (CN); Lei Shi, Shanghai (CN); Ying Shi, Shanghai (CN); Bing Shuang, Shanghai (CN); Haijun Zhao, Shanghai (CN); Wenhua Wang, Shanghai (CN); Shuang Sun, Shanghai (CN); and Siyu Liu, Shanghai (CN)
Assigned to Schneider Electric Industries SAS, Rueil-Malmaison (FR)
Filed by Schneider Electric Industries SAS, Rueil-Malmaison (FR)
Filed on Jul. 16, 2021, as Appl. No. 17/377,824.
Claims priority of application No. 202010685927.9 (CN), filed on Jul. 16, 2020.
Prior Publication US 2022/0021279 A1, Jan. 20, 2022
Int. Cl. H02K 11/25 (2016.01); G01R 31/34 (2020.01); H02H 7/085 (2006.01)
CPC H02K 11/25 (2016.01) [G01R 31/343 (2013.01); H02H 7/0852 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A motor thermal protection device which utilizes a power supply of a motor for power supplying, the motor thermal protection device comprises:
a capacitor timing circuit, configured to time after the motor is powered off;
a power-off time determining unit, configured to perform a reading operation of reading an output voltage of the capacitor timing circuit after the motor is powered on, and determine a power-off time from when the motor is powered off to when the motor is powered on according to the output voltage; and
a heat accumulation calculating unit, configured to calculate a remaining heat accumulation when the motor is powered on according to the power-off time determined by the power-off time determining unit and a heat accumulation when the motor is powered off, wherein:
the capacitor timing circuit comprises a power supply unit, a capacitor, a first resistor, a semiconductor switch module, a charging terminal, and an output terminal;
the power supply unit is powered by a power supply of the motor and outputs a voltage to be applied to a control terminal of the semiconductor switch module, after the motor is powered off, the power supply unit stops outputting the output voltage to be applied to the control terminal of the semiconductor switch module;
the semiconductor switch module comprises a first terminal, a second terminal and the control terminal, the control terminal of the semiconductor switch module controls the first terminal and the second terminal of the semiconductor switch module to be conducted when receiving the voltage output by the power supply unit, the first terminal of the semiconductor switch module is connected to a first terminal of the capacitor, and the second terminal of the semiconductor switch module is connected to the charging terminal and the output terminal;
a second terminal of the capacitor is grounded;
a first terminal of the first resistor is connected to the first terminal of the capacitor, and a second terminal of the first resistor is grounded; and
the power-off time determining unit is connected to the charging terminal and the output terminal, the power-off time determining unit performs the reading operation through the output terminal after the motor is powered on, and performs a charging operation of providing a capacitor charging voltage to the capacitor timing circuit through the charging terminal after the reading operation is completed.