An electronic expansion valve includes an electromagnetic coil, a valve body provided with a valve port, and a valve needle. The valve needle includes a main body section and a first conical surface portion arranged adjacent to the main body section. The valve port includes a straight section portion having equal diameters. When the electromagnetic coil applies a zero pulse, the straight section portion is not in contact with the valve needle, and an intersecting surface of a plane, where a top end of the straight section portion is located, and the valve needle is on the first conical surface portion. With the electronic expansion valve, flow can be precisely adjusted at a low-pulse stage, and during assembly, a position of the 0 pulse can be directly obtained by adjusting relative positions of the valve needle and the valve port and by using a flow meter.

A refrigeration apparatus including a compressor (301), a condenser (302), an expansion device (304), and an evaporator (305), fluidly connected to form a refrigeration cycle for a refrigerant, wherein the compressor (301) has a variable working capacity, and wherein the expansion device (304) has a configurable flow resistance with respect to the refrigerant passing through the expansion device. The apparatus further includes a controller (300) which is configured to determine a current working capacity of the compressor (301) and to control the resistance of the expansion device (304) in dependence on the current working capacity of the compressor (301). The controller (300) is further configured to control the resistance of the expansion device (304) in order to achieve a mass flow of the refrigerant through the expansion device (304), which mass flow corresponds to a mass flow of the refrigerant through the compressor (301).

A method of maintaining a fluid flow rate in a heating, ventilating, air conditioning, and refrigeration (HVAC-R) system while maintaining superheat in the HVAC-R system at a desired level includes: continuously measuring an operating fluid temperature of the HVAC-R system, continuously calculating HVAC-R system superheat at a pre-determined rate, determining if the calculated HVAC-R system superheat is stable, measuring and recording the operating fluid pressure of the HVAC-R system each time the calculated HVAC-R system superheat is stable, recording an average operating fluid pressure each subsequent time the superheat is stable, calculating an output PWM according to the equation: Output PWM=(Flow Rate Component)+(Superheat Component), and reducing fluid flow through a metering valve in the HVAC-R system when an actual HVAC-R system PWM is greater than the calculated output HVAC-R system PWM by adjusting a PWM signal to a microvalve in the metering valve, and increasing fluid flow through the metering valve in the HVAC-R system when the actual HVAC-R system PWM is less than the calculated output HVAC-R system PWM by adjusting the PWM signal to the microvalve in the metering valve.

Systems and methods for disrupting a flow of refrigerant within a heat exchanger assembly. One embodiment provides a method that includes receiving, with a controller, a first signal from a first sensor, the first signal indicative of a pressure of the refrigerant flowing through the heat exchanger. The method includes setting, with the controller, an operating frequency of a valve based on the first signal. The operating frequency includes a rate at which the valve actuates between a first valve position that sets a first refrigerant flow rate through the heat exchanger and a second valve position that sets a second refrigerant flow rate through the heat exchanger. The method includes controlling, with the controller, operation of a solenoid to actuate the valve at the operating frequency.

A cooling system is disclosed. The cooling system may have an evaporator, an evaporator fan, a condenser, and at least one compressor. The compressor may be either a single speed or a variable speed compressor. In addition, the system can use a mechanical or electrical pulsed operation refrigerant flow control valve for controlling refrigerant flow to the evaporator.

Various embodiments of the teachings herein include a cold exchange system. An example includes: thermal energy exchangers connected to a refrigerant pipe system; and a control system comprising: an orifice adjusting system including a valve and an actuator, the valve comprising a flow chamber with an adjustable orifice in the pipe; a position sensor to sense a position of the adjustable orifice and/or the actuator and generate a signal indicative of the sensed position; and a controller. The orifice adjusting system adjusts the adjustable orifice in response to a control signal. The control system uses a software-wise change of a characteristic curve of the orifice adjusting system. The position sensor operates using a static measurement principle. The controller compares the signal to a set position of the adjustable orifice and generates the control signal based on the comparison.

An electronic expansion valve includes an electromagnetic coil, a valve body provided with a valve port, and a valve needle. The valve needle includes a main body section and a first conical surface portion arranged adjacent to the main body section. The valve port includes a straight section portion having equal diameters. When the electromagnetic coil applies a zero pulse, the straight section portion is not in contact with the valve needle, and an intersecting surface of a plane, where a top end of the straight section portion is located, and the valve needle is on the first conical surface portion. With the electronic expansion valve, flow can be precisely adjusted at a low-pulse stage, and during assembly, a position of the 0 pulse can be directly obtained by adjusting relative positions of the valve needle and the valve port and by using a flow meter.

Disclosed is an electronic expansion valve. The electronic expansion valve includes a valve seat provided with a valve cavity and a valve port, wherein the valve port is arranged at an end portion of the valve cavity; a guide sleeve fixedly arranged on the valve seat, the guide sleeve is provided with a first guide hole, and the first guide hole is in communication with the valve cavity; and a valve needle movably arranged in the guide sleeve, wherein a first end of the valve needle penetrates out of the first guide hole to be arranged corresponding to the valve port, the valve needle is in clearance fit with the first guide hole, the valve needle is configured to control the valve port to be opened or closed, and a swingable amplitude of the valve needle in the first guide hole ranges from 0.4 to 2.4.