Electronic Expansion Valve Control Optimization in HVAC

Control system for HVAC systems that optimizes refrigerant flow through the evaporator coil by dynamically regulating the electronic expansion valve. The system employs a master control algorithm that combines feed-forward control and PID control strategies to determine the optimal electronic expansion valve position based on compressor characteristics and external temperature. This enables precise control of refrigerant flow into the evaporator coil while maintaining optimal superheat conditions. The system can operate in three modes: start-up, compressor speed change, and load change, with the master control algorithm automatically switching between these modes based on compressor operating conditions.

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Electronic expansion valve control method for air source heat pumps that improves system stability and efficiency by dynamically adjusting valve opening based on temperature rate of change. The method calculates a rate of change parameter C between current and previous temperature values, then uses this parameter to determine the precise control parameter K for the expansion valve. This enables precise control of valve opening while maintaining system stability and energy efficiency, particularly when temperature changes are small but precise adjustments are required.

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Electronic expansion valve control method, device, and equipment for maintaining consistent cooling and heating performance in multi-story buildings. The method and device enable reliable operation of outdoor units in non-standard installation heights by dynamically adjusting expansion valve settings. The control system monitors outdoor unit performance and adjusts expansion valve flow rates to maintain optimal system operation, even when the outdoor unit is not at the same height as the indoor unit. This ensures consistent indoor comfort while minimizing the impact of installation height differences.

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Control system for electronic expansion valves in heat pumps that optimizes refrigerant flow while preventing compressor failure. The system uses advanced temperature-based control to balance suction and discharge pressures, eliminating the need for separate sensors for each mode. It calculates ideal discharge temperatures and differential temperatures from system parameters, then adjusts expansion valve operation based on these values. The system maintains a predefined threshold of controlled expansion valve steps to prevent excessive flow during normal operation, while automatically detecting and correcting anomalies during abnormal conditions. This approach enables precise control of expansion valve operation while maintaining system performance and preventing potential compressor damage.

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A method for controlling electronic expansion valves in multi-split systems by dynamically adjusting valve opening based on temperature differences between indoor and outdoor units. The method uses temperature compensation values for both the outdoor unit's piping and the indoor unit's evaporator to accurately determine superheat levels. By comparing the indoor unit's actual superheat against a target value, the method calculates the necessary valve opening adjustment to maintain system balance and prevent over- or under-expansion. This approach eliminates the common issues of temperature-based valve control, particularly in long-piping systems or multi-unit environments, while maintaining precise temperature control across all units.

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Air-conditioning apparatus that prevents liquid backflow in the system by dynamically controlling expansion valve operation. The apparatus includes a controller that monitors refrigerant flow rates through the expansion valve and determines when the valve is clogged. When the valve is clogged, the controller activates a bypass valve to maintain system operation while preventing liquid backflow. This approach ensures continuous refrigerant flow through the system, preventing compressor damage and maintaining optimal compressor performance.

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Real-time control of electronic expansion valves in air conditioning systems and battery water cooling systems through advanced temperature and pressure sensing. The control system integrates temperature and pressure signals from the valve outlet to determine superheat levels, enabling precise temperature control, superheat management, and precise valve opening. This integrated sensing approach enables more accurate and reliable valve operation compared to traditional single-point sensing methods.

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Electronic expansion valve control method that improves performance and efficiency of air conditioning systems. The method involves calculating equivalent exhaust temperatures from actual exhaust temperatures, rather than comparing actual and target exhaust temperatures. This approach enables precise control of the expansion valve by adjusting its opening based on the equivalent exhaust temperature, rather than relying on the conventional relationship between actual and target exhaust temperatures. The equivalent temperature calculation process eliminates the lag associated with traditional exhaust temperature comparisons, resulting in faster and more accurate valve adjustments.

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A control method for electronic expansion valves in air conditioning systems that improves efficiency and stability through adaptive control. The method employs a combination of superheating and subcooling control parameters to dynamically adjust expansion valve opening, while incorporating room temperature considerations. The control system uses fuzzy logic to combine pre-calibrated parameters for superheating and subcooling with the room temperature, enabling precise valve opening adjustments. This approach enhances system performance by leveraging the specific characteristics of each parameter while maintaining optimal system balance.

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Method and device for precise electronic expansion valve opening control in heat pump systems. The method and device achieve improved performance by dynamically adjusting expansion valve opening based on actual exhaust gas superheat conditions. When the actual exhaust temperature falls within the target range, the valve opening is gradually increased to maintain system stability. This approach eliminates the need for abrupt valve adjustments, which can lead to over- or under-adjustment. The method and device maintain precise control over the expansion valve while minimizing temperature fluctuations and system parameter variations, thereby enhancing system reliability and performance.

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A method for intelligent control of liquid injection electronic expansion valves in air conditioners that prevents excessive valve opening and liquid return. The method optimizes valve operation based on real-time ambient and exhaust temperature conditions, using a sophisticated algorithm that dynamically adjusts valve opening degree. This approach eliminates the linear adjustment limitations of traditional control methods, ensuring precise temperature control and preventing excessive liquid return. The method is implemented in air conditioners with electronic expansion valves, enabling more efficient and reliable operation.

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Electronic expansion valve control method and device for air conditioners that enables precise control of the valve's opening based on compressor frequency changes and system pressure conditions. The method employs a target superheat and exhaust temperature control strategy to rapidly adjust the valve's opening, eliminating the need for traditional superheat-based adjustments. This approach ensures optimal system balance during compressor frequency changes or high-temperature events, preventing shutdowns and maintaining comfortable indoor conditions.

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Electronic expansion valve control method and device for air conditioning systems that rapidly achieve target exhaust temperatures through precise control of the expansion valve's opening. The method involves determining the target exhaust temperature based on outdoor ambient conditions and continuously monitoring the current exhaust temperature. When the temperature difference between the current and target values exceeds a predetermined threshold, the control system automatically adjusts the expansion valve opening to rapidly approach the target temperature. This approach eliminates the time-consuming search-and-decrement process typically used in traditional expansion valve control methods.

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Electronic expansion valve control method and device for air conditioners that optimizes valve operation in ultra-low temperature environments. The method employs a dynamic adjustment strategy that adapts to the actual DSH (Demand-Satisfaction Heat) value of the system, rather than relying on fixed time-based adjustments. When the outdoor temperature is below a predetermined threshold, the system automatically switches to ultra-low temperature operation and closes the electronic expansion valve. The control system then calculates the DSH difference between the actual and target values, determining the optimal valve opening period. This adaptive approach ensures precise control of the expansion valve during ultra-low temperature operation, preventing excessive pressure drops and maintaining system performance.

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Electronic expansion valve control system for refrigeration systems that dynamically adjusts valve opening based on temperature and refrigerant flow rates. The system uses advanced algorithms to calculate optimal valve opening positions and compensates for temperature variations. This enables precise control of refrigerant flow while maintaining optimal refrigerant capacity and system performance. The system employs automatic and correction mechanisms to continuously monitor and adjust valve performance.

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Electronic expansion valve control system that improves real-time and accuracy of valve operation in air conditioning and battery cooling systems. The system employs a temperature- and pressure-based control approach that continuously monitors the valve's performance parameters and adjusts the control mode based on real-time conditions. This enables precise control of valve opening and flow, enhancing system efficiency and reliability.

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Controlling the electronic expansion valve in a jet enthalpy heat pump system to optimize performance and reliability. The control system monitors system parameters such as exhaust gas temperature, operating frequency, outlet water temperature, and outer loop temperature, and adjusts the electronic expansion valve opening accordingly. The system employs a dynamic control strategy that adapts to different operating modes, including heating and cooling, by linking the valve opening to the system's operating parameters. This approach ensures precise control of the expansion valve while maintaining compressor performance and prolonging its lifespan.

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Electronic expansion valve control for inverter air conditioners that enhances heating capacity and stability. The control method and device optimize expansion valve operation by dynamically adjusting its opening degree, enabling more efficient refrigerant flow and improved system performance, particularly during low-temperature heating cycles.

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Control method and control system for electronic expansion valves in air conditioning systems that improves energy efficiency by precisely compensating for fan-driven temperature deviations. The system calculates the optimal target exhaust temperature for the compressor based on the fan speed, rather than relying solely on compressor operating conditions. This approach ensures accurate temperature control across varying fan speeds, mitigating the typical issues of excessive valve opening at low fan speeds and energy inefficiencies. The system also incorporates a compensation factor for wind speed variations, enabling precise control of the expansion valve's opening degree.

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Improving the performance of electronic expansion valve (EEV) control in air conditioning systems through adaptive PID control. The method enables dynamic adjustment of EEV opening based on real-time temperature deviations from the setpoint, enabling more accurate temperature control and improved energy efficiency. The adaptive control mechanism continuously calculates temperature deviations from the setpoint and applies corrective adjustments to the EEV opening rate, allowing the system to dynamically respond to changing operating conditions.

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