| CPC H02P 1/42 (2013.01) [D06F 34/08 (2020.02); D06F 34/10 (2020.02); D06F 34/20 (2020.02); D06F 58/26 (2013.01); D06F 58/38 (2020.02); G01R 31/343 (2013.01); H02P 1/028 (2013.01); H02P 23/0004 (2013.01); H02P 23/14 (2013.01); H02P 25/062 (2016.02); H05K 7/209 (2013.01); D06F 2103/24 (2020.02); D06F 2103/46 (2020.02); D06F 2105/28 (2020.02); D06F 2105/48 (2020.02)] | 22 Claims |

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1. An electronic starting switch assembly for controlling operation of a dryer having a heating element and having a split-phase induction motor having a main winding and an auxiliary winding wrapped around a stator for rotation of a rotor having a rotor speed, an induction motor power supply and a heater element power supply, the electronic starting switch assembly comprising:
a microcontroller unit (MCU) configured to execute a control method for operating the dryer, including control of the split-phase induction motor of the dryer;
a memory configured to store parameters for a crossover condition;
sensing circuitry for sensing characteristics of the split-phase induction motor;
power switch circuits configured to connect and disconnect the auxiliary winding of the split-phase induction motor and the heater element respectively to the induction motor power supply and the heater element power supply;
wherein the MCU is configured to:
load a crossover coefficient from memory;
connect the auxiliary winding to the induction motor power supply to start ramping the rotor speed during a starting period of operation;
real-time sample a main winding current and an auxiliary winding current to generate a real-time samplings of the main winding current and the auxiliary winding current;
calculate stabilized startup forward magnitude current based on the main winding current and the auxiliary winding current;
determine and store in memory a crossover condition based on the stabilized startup forward magnitude current and the crossover coefficient;
monitor startup real-time forward magnitude current based on the real-time samplings of the main winding current and the auxiliary winding current during a startup period where the auxiliary winding is connected to the induction motor power supply;
determine that the startup real-time forward magnitude current meets the crossover condition and in response 1) disconnect the auxiliary winding from the induction motor power supply; and 2) connect the heater element to the heater element power supply.
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