Supplemental electric heater assembly for a heat pump

Abstract

Described herein is a supplemental electric heater assembly for a heat pump. The assembly comprises a plurality of electric heaters, each having a different heating capacity value, wherein the heating capacity values of the plurality of electric heaters are in a geometric progression.

1 . A supplemental electric heater assembly for a heat pump, the supplemental electric heater assembly comprising:
 a plurality of electric heaters, each having a different heating capacity value, wherein the heating capacity values of the plurality of electric heaters are in a geometric progression.   
     
     
         2 . The supplemental electric heater assembly of  claim 1 , wherein the heating capacity values of the plurality of electric heaters are in the geometric progression by a multiple of two or having a common ratio of 2. 
     
     
         3 . The supplemental electric heater assembly of  claim 1 , wherein the assembly is configured downstream or upstream of an indoor coil associated with the heat pump. 
     
     
         4 . The supplemental electric heater assembly of  claim 1 , wherein the heat pump is associated with a heating, ventilation, and air conditioning (HVAC) system that is configured to supply air to an area of interest (AOI), wherein the supplemental electric heater assembly comprises a controller operatively connected to each of the plurality of electric heaters and the heat pump, and wherein the controller is configured to:
 receive data pertaining to a predefined temperature for the air to be supplied to the AOI;   monitor real-time temperature of the air downstream of an indoor coil of the heat pump; and   operate, based on the real-time temperature and the predefined temperature, the heat pump and/or at least one of the plurality of electric heaters to adjust the temperature of the air being supplied to the AOI to the predefined temperature.   
     
     
         5 . The supplemental electric heater assembly of  claim 4 , wherein the controller is a digital control circuitry that comprises one or more processors coupled to a memory storing instructions executable by the one or more processors, which causes the controller to operate the heat pump and/or individually control switching of each of the electric heaters. 
     
     
         6 . The supplemental electric heater assembly of  claim 4 , wherein the assembly or the controller comprises a plurality of control switches, each electrically configured between an electrical power source and one of the plurality of electric heaters, and wherein each of the plurality of control switches comprises:
 a triode for alternating current (TRIAC) electrically connected in series with a heating element associated with a corresponding electric heater from the plurality of electric heaters; and   a gate triggering circuit connected to a gate terminal associated with the TRIAC, wherein the gate triggering circuit is configured to control one or more of a firing angle, a switching frequency, and a switching duration of the TRIAC per cycle of the electrical power to adjust root means square (RMS) value of current supplied by the electric power source to the corresponding heating element via the TRIAC.   
     
     
         7 . The supplemental electric heater assembly of  claim 6 , wherein the gate triggering circuit comprises:
 a voltage sensor electrically connected to the power source to monitor voltage of the electrical power being supplied by the power source;   a zero-crossing detector connected to the voltage sensor to monitor zero-crossing points of a sine waveform associated with the monitored voltage by tracking a change in the waveform from positive to negative or vice versa while the waveform crosses Zero voltage;   a flip-flop connected to an output of the zero-crossing detector; and   a delay circuit configured between a Q-output of the flip-flop and the gate terminal associated with the TRIAC,   wherein the flip-flop is configured to actuate the delay circuit upon detection of the zero-crossing points in the voltage waveform, which causes the delay circuit to trigger the gate of the TRIAC after a predefined time from the zero-crossing points in the voltage waveform to adjust the firing angle of the TRIAC to a predefined value, thereby adjusting the RMS value of the current supplied by the power source to the corresponding heating element.   
     
     
         8 . The supplemental electric heater assembly of  claim 7 , wherein the TRIAC and one or more components associated with the gate triggering circuit are configured on a printed circuit board. 
     
     
         9 . The supplemental electric heater assembly of  claim 4 , wherein the controller is configured to stop the operation of the plurality of electric heaters when occupants are detected to be absent within the AOI and/or when temperature outside of the AOI is above the predefined temperature. 
     
     
         10 . A supplemental electric heater assembly for a heat pump, the supplemental electric heater assembly comprising:
 a first set of electric heaters, each having a fixed electric heating capacity value; and   a second set of electric heaters having a variable heating capacity value, the second set of electric heaters are configured parallelly to the first set of electric heaters, wherein the second set of electric heaters has a maximum heating capacity value equal to the electric heating capacity value associated with an electric heater having a minimum heating capacity value among the first set of electric heaters.   
     
     
         11 . The supplemental electric heater assembly of  claim 10 , wherein the heating capacity values of at least two electric heaters among the first set of electric heaters are the same. 
     
     
         12 . The supplemental electric heater assembly of  claim 10 , wherein the heating capacity values of at least two electric heaters among the first set of electric heaters are different. 
     
     
         13 . The supplemental electric heater assembly of  claim 10 , wherein each electric heater in the first set of electric heaters has a different heating capacity value, and wherein the heating capacity values of the first set of electric heaters are in a geometric progression by a multiple of two. 
     
     
         14 . The supplemental electric heater assembly of  claim 10 , wherein the supplemental electric heater assembly is configured downstream or upstream of an indoor coil associated with the heat pump. 
     
     
         15 . The supplemental electric heater assembly of  claim 10 , wherein the heat pump is associated with a heating, ventilation, and air conditioning (HVAC) system that is configured to supply conditioned air to an area of interest (AOI), wherein the supplemental electric heater assembly comprises a controller operatively connected to each of the first set of electric heaters, the second set of electric heaters, and the heat pump, and wherein the controller is configured to:
 receive data pertaining to a predefined temperature for the air to be supplied to the AOI;   monitor real-time temperature of the air downstream of an indoor coil of the heat pump; and   operate, based on the real-time temperature and the predefined temperature, any or a combination of the heat pump, at least one of the first set of electric heaters, and the second set of electric heaters to adjust the temperature of the air being supplied to the AOI to the predefined temperature.   
     
     
         16 . The supplemental electric heater assembly of  claim 15 , wherein the controller is a digital control circuitry that comprises one or more processors coupled to a memory storing instructions executable by the one or more processors, which causes the controller to operate the heat pump and/or individually control switching of each of the first set or second set of electric heaters. 
     
     
         17 . The supplemental electric heater assembly of  claim 15 , wherein the supplemental electric heater assembly or the controller comprises a plurality of control switches, each electrically configured between an electrical power source and one of the electric heaters, and wherein each of the plurality of control switches comprises:
 a triode for alternating current (TRIAC) electrically connected in series with a heating element associated with a corresponding electric heater from the first set of electric heaters or the second set of electric heaters; and   a gate triggering circuit connected to a gate terminal associated with the TRIAC, wherein the gate triggering circuit is configured to control one or more of a firing angle, a switching frequency, and a switching duration of the TRIAC per cycle of the electrical power to adjust root means square (RMS) value of current supplied by the power source to the corresponding heating element via the TRIAC.   
     
     
         18 . The supplemental electric heater assembly of  claim 17 , wherein the gate triggering circuit comprises:
 a voltage sensor electrically connected to the power source to monitor voltage of the electrical power being supplied by the power source;   a zero-crossing detector connected to the voltage sensor to monitor zero-crossing points of a sine waveform associated with the monitored voltage by tracking a change in the waveform from positive to negative or vice versa while the waveform crosses Zero voltage;   a flip-flop connected to an output of the zero-crossing detector; and   a delay circuit configured between a Q-output of the flip-flop and the gate terminal associated with the TRIAC,   wherein the flip-flop is configured to actuate the delay circuit upon detection of the zero-crossing points in the voltage waveform, which causes the delay circuit to trigger the gate of the TRIAC after a predefined time from the zero-crossing points in the voltage waveform to adjust the firing angle of the TRIAC to a predefined value, thereby adjusting the RMS value of the current supplied by the power source to the corresponding heating element.   
     
     
         19 . The supplemental electric heater assembly of  claim 17 , wherein the TRIAC and one or more components associated with the gate triggering circuit are configured on a printed circuit board. 
     
     
         20 . The supplemental electric heater assembly of  claim 15 , wherein the controller is configured to stop the operation of the first set of electric heaters or the second set of electric heaters when occupants are detected to be absent within the AOI and/or when temperature outside of the AOI is above the predefined temperature.