Abstract: The present invention relates to a system and method of controlling a linear compressor (10), which is capable of fine-tuning the compressor when necessary, throughout the operating period of the compressor, so that said compressor operates at maximum capacity, wherein the piston (1) achieves a maximum displacement amplitude, closely approaching the cylinder head (2) without colliding with it. The system and the method according to the invention are also intended to control the operation of the linear compressor throughout its operating period, also seeking to maximize its performance and to reduce or optimize its power consumption. According to the present invention, the fine-tuning and control of the operation of the linear compressor are carried out by means of the combination of a technique for controlling a compressor without a sensor, and a technique for controlling the compressor with the aid of a sensor.

Abstract: A linear compressor (100) applicable to a cooling system (20) includes a piston (1) driven by a linear motor (10), the piston (1) having displacement range controlled by means of a controlled voltage (VM), the controlled voltage (VM) having a voltage frequency (?P) applied to the linear motor (10) and adjusted by a processing unit (22), the range of piston (1) displacement being dynamically controlled in function of a variable demand of the cooling system (20), the linear compressor (100) having a resonance frequency, the processing unit (22) adjusting the range of piston (1) displacement, so that the linear compressor (100) will be dynamically kept on resonance throughout the variations in demand of the cooling system (20).

Abstract: A linear compressor control system includes an electronic circuit controlling an electric motor that drive a piston of the compressor, such that the motor is operated intermittently with an on-time (tL) and an off-time (tD) to keep the compression capacity of the compressor substantially constant. The compressor is associated with a closed cooling circuit having an evaporator and a condenser. The off-time (tD) is shorter than the time necessary for the evaporation pressure (PE) in the evaporator and the condensation pressure (Pc) in the condenser to equalize each other after the compressor has been turned off.

Abstract: A linear motor (10), a linear compressor (100), a method of controlling a linear compressor (100), a cooling system (20) and a system of controlling a linear compressor (100) to operate a linear compressor (100) in resonance in it's the greatest possible efficiency throughout its operation are described.

Abstract: The present invention relates to a system and method of controlling a linear compressor (10), which is capable of fine-tuning the compressor when necessary, throughout the operating period of the compressor, so that said compressor operates at maximum capacity, wherein the piston (1) achieves a maximum displacement amplitude, closely approaching the cylinder head (2) without colliding with it. The system and the method according to the invention are also intended to control the operation of the linear compressor throughout its operating period, also seeking to maximize its performance and to reduce or optimize its power consumption. According to the present invention, the fine-tuning and control of the operation of the linear compressor are carried out by means of the combination of a technique for controlling a compressor without a sensor, and a technique for controlling the compressor with the aid of a sensor.

Abstract: A method of detecting the occurrence of impact or collision between a cylinder (2) and piston (1) driven by a linear motor of a gas compressor includes the steps of i) obtainment of a reference signal (Sr) associated to an electrical output of the linear motor before the piston attains the upper dead center; ii) obtainment of a detection signal (Sd) associated to said electrical output of the linear motor after the piston attains the upper dead center; iii) comparison between the reference signal (Sr) and the detection signal (Sd); and iv) record of occurrence of impact when the result of comparison of step iii indicates that the detection signal (Sd) presents a variation deriving from impact between the cylinder (2) and the piston (1), considering a pre-established tolerance. Also disclosed is an electronic detector device capable of executing the methodology described above. A gas compressor (100) and a control system including the above-mentioned detector are also disclosed.

Abstract: The present invention discloses a piston and cylinder combination driven by linear motor with cylinder position recognition system, comprising a support structure (4) forming an air gap (12); a motor winding (6) generating a variable magnetic flow at least along part of the air gap (12); a cylinder (2) having a head at one of its ends; a piston (1) connected to a magnet (5), the magnet being driven by the magnetic flow of the motor winding (6) to move inside a displacement path including at least partially the air gap (12); the displacement of the magnet making the piston (1) reciprocatingly move inside the cylinder (2); and an inductive sensor (8) disposed at a point of the displacement path of the magnet (5), such that when the piston (1) reaches a position of closest approach to the cylinder head, the inductive sensor detects a variation in the magnetic field resulting from the corresponding position of the magnet, and generates a voltage signal arising from this magnetic field variation.

Abstract: The present invention relates to a system of controlling a piston in a linear compressor, a method of controlling a piston in a linear compressor, as well as a linear compressor, particularly applicable to cooling systems that may include, for instance, refrigerators, air-conditioning systems and the like.

Abstract: A linear compressor control system includes an electronic circuit controlling an electric motor that drive a piston of the compressor, such that the motor is operated intermittently with an on-time (tL) and an off-time (tD) to keep the compression capacity of the compressor substantially constant. The compressor is associated with a closed cooling circuit having an evaporator and a condenser. The off-time (tD) is shorter than the time necessary for the evaporation pressure (PE) in the evaporator and the condensation pressure (Pc) in the condenser to equalize each other after the compressor has been turned off.

Abstract: The present invention provides an electric motor movement controlling method, where the electric motor is fed by a total voltage proportional to the network voltage. The method comprises steps of making a first measurement of level of the network voltage at a first moment of measurement and making a second measurement of level of the network voltage; at a second moment of measurement, calculating the value of the derivative of the values of voltage measured in function of the first and second moments of measurement, to obtain a value of a proportional network voltage, and altering the value of the total voltage fed to the motor, proportionally to the value of the proportional network. A system that will implement the steps of the method of the present invention, as well as a compressor comprising the system of the present invention are foreseen.

Abstract: A system and a method for protecting electric motors and their respective control circuits are described, wherein it is possible to distinguish whether a situation of surge current results from a overload or from a short-circuit on the motor (1). This is achieved by means of a system for protecting an electric motor (1) and its control circuit (2), the motor speed control being carried out by means of a set of switches (Ch), the system comprising a control central (7) capable of measuring the electricity conduction time (Tc) of each of the switches (Ch) and to measure the time (Td) passed between the beginning of conduction of one of the switches (Ch) and the occurrence of a surge current, the central (7) making a comparison of said times (Td, Tc) and being capable of determining whether said surge current results from an overload or a short-circuit of the electric motor (1) or on one of the switches (Ch).

Abstract: A method for controlling and protecting electric motors, specially permanent magnet motors electronically actuated by a control system. The system includes a three-phase inverting bridge, in which the position of the rotor can be monitored by using a position detector physically attached to the axle or through the tension induced in the coils by the magnet, in order to correctly control actuation by the control system. The present invention is also directed to a system for controlling electric motors and an electric motor system. The system includes continuously reading the position detector until a minimum expected time has passed. After the minimum expected time has passed, there is continuous reading of the position detector until a maximum expected time has passed to detect if a position change of the rotor is sensed.

Abstract: A system and method for controlling a compressor (1) is provided that prevents the piston (5) of the compressor from colliding against the valve system (8, 9) provided therein. The system and method of the present invention control the stroke of the piston (5), allowing the piston (5) to advance as far as the end of its mechanical stroke in extreme conditions of load, without allowing the piston (5) to collide with the valve system (8,9). The present invention controls the compressor (1) by measuring a movement time of the piston (5); comparing the movement time with a foreseen movement time; and altering the voltage (Vm) if the first movement time is different from the foreseen movement time, the foreseen movement time being such that the movement of the piston (5) will reach a maximum point (M).

Abstract: A system and method for controlling a compressor (1) is provided that prevents the piston (5) of the compressor from colliding against the valve system (8, 9) provided therein. The system and method of the present invention control the stroke of the piston (5), allowing the piston (5) to advance as far as the end of its mechanical stroke in extreme conditions of load, without allowing the piston (5) to collide with the valve system (8,9). The present invention controls the compressor (1) by measuring a movement time of the piston (5); comparing the movement time with a foreseen movement time; and altering the voltage (Vm) if the first movement time is different from the foreseen movement time, the foreseen movement time being such that the movement of the piston (5) will reach a maximum point (M).

Abstract: A driving control system for electric motors, of the type used in refrigeration compressors and including: a power source (20) in direct current having, between positive (21) and negative (22) terminals of equal voltage, a median terminal (25), of null voltage, to which is directly connected a first coil (11) of the electric motor (10); an inverter (30) provided with N−1 commutation arms with opposite ends connected to the power source (20) and each including switch means, each commutation arm being medianly connected to a respective coil; and a control unit (40) operating the switch means, as a function of the signals received from a position sensor means (50), in order to determine to said switch means, in each of a first and a second switching condition thereof, a switching frequency and a switch conduction period, which are defined in order to be effectively applied to the coils a voltage effectively corresponding to the speed and torque required for the motor.