Optimizing energy efficiency ratio feedback control for direct expansion air-conditioners and heat pumps
AssigneeAdvantek Consulting Engineering, Inc.
InventorMichael Kenneth West
Life of this patent
Estimating the term…
Abstract
Measured EER and COP are affected by the load under which an air conditioning, refrigeration or heating system is running; the load is a function of the evaporating and condensing temperatures. The invention makes adjustments for the purpose of maximizing measured EER and COP in a feedback loop utilized to optimize cooling or heating capacity relative to power consumed. The maximum EER is continuously achieved by incrementally adjusting each operating parameter to realize an incremental increase in EER, even as conditions such as ambient temperature are changing.
Claims8
A system for maximizing the energy efficiency ratio or coefficient of performance of an air conditioner or a heat pump comprising:
- a first pressure sensor adapted to measure a first refrigerant pressure selectively at a condenser outlet or a condenser inlet and to generate a first pressure signal indicative of the first refrigerant pressure;
- a first temperature sensor adapted to measure a first refrigerant temperature at an evaporator outlet and to generate a first temperature signal indicative of the first refrigerant temperature;
- a second pressure sensor adapted to measure a second refrigerant pressure at the evaporator outlet or a compressor inlet and to generate a second pressure signal indicative of the second refrigerant pressure;
- a second temperature sensor adapted to measure a second refrigerant temperature selectively at a condenser outlet and to generate a second temperature signal indicative of the second refrigerant temperature;
- a flow sensor adapted to measure a refrigerant flow rate and to generate a flow signal indicative of the refrigerant flow rate;
- a power voltage sensor configured to measure an electrical voltage input to the air conditioner or the heat pump and generate a power voltage signal proportional to the electrical voltage input;
- a power current sensor configured to measure an electrical current input to the air conditioner or the heat pump and to generate a power current signal proportional to the electrical current input;
- and
- a processor in electrical communication with the first pressure sensor, the first temperature sensor, the second pressure sensor, the second temperature sensor, the flow sensor, the power voltage sensor, and the power current sensor, wherein the processor is adapted to receive the first pressure signal, the first temperature signal, the second pressure signal, the second temperature signal, the flow signal, the power voltage signal, and the power current signal;
- wherein the processor is configured to calculate a first enthalpy based on the first pressure signal;
- wherein the processor is configured to calculate a second enthalpy based on the second pressure signal;
- wherein the processor is configured to calculate a measured energy efficiency ratio or a coefficient of performance as the difference between the first enthalpy the second enthalpy divided by a value proportional to the power voltage signal or the power current signal;
- wherein the processor is configured to provide an evaporator fan motor speed control signal to an evaporator fan motor;
- wherein the processor is configured to provide a condenser fan motor speed control signal to a condenser fan motor;
- wherein the processor is configured to provide a compressor control signal to a compressor;
- and
- wherein the processor is configured to adjust the value of one or more of the evaporator fan motor speed control signal, condenser fan motor speed control signal, or compressor control signal based on the calculated measured energy efficiency ratio or coefficient of performance.
Dependencies are inferred from the claim text.