US 11,990,743 B2
Half-wave condition detection in electrical appliances
Christopher Lee Hettinger, Louisville, KY (US)
Assigned to Haier US Appliance Solutions, Inc., Wilmington, DE (US)
Filed by Haier US Appliance Solutions, Inc., Wilmington, DE (US)
Filed on Sep. 23, 2022, as Appl. No. 17/951,990.
Prior Publication US 2024/0106227 A1, Mar. 28, 2024
Int. Cl. H02H 7/08 (2006.01); H02H 7/085 (2006.01)
CPC H02H 7/0844 (2013.01) [H02H 7/085 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A system for detecting a half-wave condition in an electrical appliance, the system comprising:
an electric motor;
a triac circuit electrically coupled to the electric motor, the triac circuit configured to control the electric motor;
a feedback circuit, the feedback circuit comprising
a dual-channel optocoupler electrically coupled to the triac circuit and the electronic controller, and
an electronic controller electrically coupled to the triac circuit and the feedback circuit, the electronic controller comprising:
one or more processors and a non-transitory, computer readable medium comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform a process, the process comprising:
providing, by the electronic controller, an input signal to the triac circuit for controlling the electric motor;
receiving, at the electronic controller, a feedback signal from the feedback circuit indicative of an output of the triac circuit, wherein the dual-channel optocoupler observes the output of the triac circuit;
determining that the feedback signal indicates a half-wave condition is present when the dual-channel optocoupler observes only one of a positive half-wave and a negative half-wave of the output of the triac circuit;
generating a shutdown signal for the electric motor; and
providing the shutdown signal, by the electronic controller, to the triac circuit.