KR20050111096A - Apparatus for controlling operation of linear compressor - Google Patents

Abstract

The present invention relates to a control device of a linear compressor, and in particular, the present invention can detect the initial stop position of the sensor core before driving the linear compressor, so that it is possible to compensate for the stroke deviation caused by the external environment such as assembly deviation of the sensor. Improves cold power deviation.

To this end, the present invention provides a position detection unit for detecting the initial stop position of the sensor core that operates in conjunction with the piston reciprocally installed in the compression chamber, and the position where the initial stop position of the sensor core detected through the position detection unit is preset. And a compressor control unit for resetting the stroke of the piston based on the deviation, and a compressor driving unit for driving the linear compressor based on the reset stroke according to the control signal of the control unit.

Description

Control device for linear compressors {Apparatus for controlling operation of linear compressor}

The present invention relates to a control device for a linear compressor, and more particularly, to a control device for a linear compressor having a sensor capable of detecting a vertical reciprocating motion of a piston of the linear compressor.

In general, the linear compressor is composed of a sealed outer casing 1, a compression part 3 for suction-pressing and discharging a refrigerant, and a driving part 5 for generating power, as shown in FIG.

The compression unit 3 is provided in the cylinder block 11 forming the compression chamber 12, the piston 10 installed in the compression chamber 12 so as to reciprocate, and the lower region of the cylinder block 11. And a cylinder head 13 in which a suction chamber (not shown) and a discharge chamber (not shown) of the refrigerant are formed.

The driving unit 5 is fixed to the inner core 15 provided to surround the outer side of the cylinder block 11 and the fixed frame 17 so as to surround the outer circumferential surface of the inner core at a predetermined interval, and the coil 45 therein. The winding is composed of an outer core 19, and a magnet 18 interposed between the inner and outer cores 19 to electromagnetically interact with the magnetic fields of the inner and outer cores 19 to reciprocate up and down. It is.

The piston 23 of the compression unit 3 is coupled to the upper end of the piston 10, one region is interposed between the inner and outer core 19 of the drive unit 5, the supporter 23 for holding and fixing the magnet 18. The mover 23 is linked to the up and down reciprocation of the magnet 18 described above, whereby the piston 10 performs the up and down reciprocating motion in the compression chamber 12.

On the other hand, the sensor core 20 of the magnetic material is installed on the outer edge of the upper end of the movable member 23, the stroke of the sensor core 20 to reciprocate up and down with the movable member 23 on the upper end of the fixed frame 17. Sensor 30 for detecting the is installed.

One end of the sensor 30 is fixed to the upper end of the columnar sensor support member 31 standing upright on the upper surface of the fixed frame 17, so that the sensor core 20 can pass through the free end of the sensor 30. The sensing hole 33 is formed, and the sensor core 20 is a pillar-shaped support member standing upright on the upper part of the movable member 23 to vertically reciprocate in the sensing hole 33 of the sensor 30 ( 21) It is fixedly installed on the upper part.

With this configuration, when an external power source is applied and the compressor is driven, the magnet 18 installed in the movable member 23 is interposed between the inner and outer cores 19 so that the magnetic fields and the electrons of the inner and outer cores 19 are increased. By virtue of interacting miraculously, the piston 10 associated with the mover 23 moves up and down reciprocally in the compression chamber 12 of the cylinder block while compressing and discharging the refrigerant. At this time, the sensor core 20 installed in the mover 23 is moved up and down in the sensing hole 33 of the sensor 30 in the same way as the stroke amount of the piston 10, the sensor 30 is By detecting the up and down reciprocating motion of the sensor core 20 is to detect the exact stroke of the piston (10).

In this way, the sensor core is installed in the mover so as to have the same stroke amount as the piston, and the sensor for detecting the up and down movement of the sensor core is provided in the fixed frame, thereby detecting the correct position and stroke amount of the piston.

The position of the sensor core of the sensor is finally determined by the deviation and the accumulated accumulation deviation of each sensor of the sensor and the pressure biased when refrigerant is injected into the compressor. At this time, the sensor core moves between the position at which the sensor core initially stops and the position when it comes to zero. The movement distance of the sensor core is the movement distance of the piston, which determines the stroke.

The top dead center of the linear compressor adjusts the sensor core to the sensor's zero point (mechanical top dead center) when assembling, so all compressors have the same top dead center regardless of the external environment, but the initial stop position of the sensor core is assembling deviation and bias. Deviation exists in each linear compressor due to an external environment such as the like.

Therefore, since the initial stop position of the sensor core is not constant, a stroke deviation occurs in each of the linen compressors, and thus, there is a problem in that a cold force deviation occurs in each linear compressor.

The present invention is to solve the above-mentioned problems, an object of the present invention is to compensate for the deviation of the stroke of the linear compressor caused by the change of the initial stop position of the sensor core linear to improve the variation of the cooling power of the linear compressor It is to provide a control device of the compressor.

In the control apparatus of the linear compressor of the present invention for achieving the above object, in the control apparatus of the linear compressor comprising a piston which is installed to reciprocate in the compression chamber, and a sensor core that operates in conjunction with the piston, the sensor A position detection unit for detecting an initial stop position of the core, a compressor control unit for resetting a stroke of the piston based on a degree out of a preset position of the sensor core detected through the position detection unit, and Comprising a compressor drive unit for driving the linear compressor based on the reset stroke in accordance with the control signal, if the initial stop position of the sensor core deviated from the reference position due to assembly deviation or cumulative deviation, etc. to compensate the stroke deviation accordingly Can improve the cold power deviation of the linear compressor. have.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

The control apparatus of the linear compressor according to the present invention includes a sensor core that operates in conjunction with a piston as in the prior art.

In addition, the control apparatus of the linear compressor according to the present invention, as shown in Figure 2, detects the initial stop position of the sensor core 20 before driving the linear compressor, and the position and stroke of the piston when the linear compressor is driven. Before the position detection unit 40 and the linear compressor are driven, the stroke of the linear compressor is reset according to the initial stop position of the sensor core, and when the linear compressor is driven, the position and the stroke amount of the piston are based on the reset stroke value. Therefore, the compressor controller 60 controls the stroke of the linear compressor, and the compressor driver 70 which drives the linear compressor by varying the voltage and phase provided to the compressor motor 80 according to the control signal of the compressor controller 60. It includes.

As illustrated in FIG. 2, the position detecting unit includes a first coil and a second coil wound symmetrically on the outside of the sensor core, and the first coil L1 and the first coil L1 of the sensor according to the position of the sensor core 20. And a first detection circuit for detecting the initial stop position of the sensor core before driving the linear compressor by using the change in inductance between the two coils L2. At this time, the position detection unit may further include a second detection circuit for detecting the position and the stroke amount of the piston when driving the linear compressor. In this case, the control device of the linear compressor according to the present invention is switched to supply power only to the first detection circuit before driving the linear compressor, and to supply power only to the second detection circuit when driving the linear compressor. It includes a switching circuit for reducing.

The first detection circuit includes the divided resistors R7 to R14 connected to the first coil L1 and the second coil L2, and the comparators OP1 and OP2 connected to the divided resistors R7 to R14. The first detection circuit detects an initial stop position of the sensor core using two comparators (OP1 and OP2) for the voltage difference represented by the position of the sensor core by applying the voltage distribution law by the resistance. The reason for using two comparators (OP1, OP2) is to determine the comparable up and down position with respect to the standard position within the position accuracy by using the carrier frequency and the distribution resistance when the standard stop position of the sensor core is determined.

The divided resistors R11 and R13 in the first detection circuit are connected in series between one end and the other end of the first coil of the sensor connected to the triangular wave generating circuit, and the comparator OP1 is connected to the connection point between the divided resistors R11 and R13. The non-inverting terminal (+) of is connected, and the divided resistors R12 and R14 are connected in series between one end and the other end of the second coil of the sensor, and at the connection point of the divided resistors R11 and R14, the comparator OP1 Inverting terminal (-) is connected. In addition, the voltage divider R7 and R9 are connected in series between one end and the other end of the first coil of the sensor connected to the triangular wave generating circuit, and the non-inverting terminal of the comparator OP2 is connected to the connection point between the voltage divider R7 and R9. (+) Is connected, the voltage divider resistors R8 and R10 are connected in series between one end and the other end of the second coil of the sensor, and the inverting terminal (-) of the comparator OP2 is connected to the connection point of the voltage divider resistors R8 and R10. ) Is connected.

In addition, the second detection circuit includes detection resistors R1 and R2 connected to the first coil L1 and the second coil L2, and comparators OP3 and OP4 connected to the voltage divider resistors R3 to R6. .

At this time, when the sensor core is positioned at a preset position (reference position), the first comparator OP1 and the second comparator OP2 output a low signal LOW, and the sensor core exceeds the reference position, When positioned on the upper side, the first comparator OP1 outputs the high signal HIGH, the second comparator OP2 outputs the low signal LOW, and the sensor core falls short of the reference position. When the lower side is located, the first comparator OP1 outputs the low signal LOW and the second comparator OP2 outputs the high signal HIGH. It is adjusted in advance.

Therefore, when the output signals of the first comparator OP1 and the second comparator OP2 are the low signal LOW, respectively, it is determined that the sensor core 30 is located at the reference position as shown in FIG. In the case of HIGH and LOW signals, as shown in FIG. 4, it is determined that the sensor core 30 is located above the reference position, and conversely, in the case of the low and high signals, It is determined that the core 30 is located below the reference position.

Therefore, when the output signals of the first comparator OP1 and the second comparator OP2 are LOW and LOW signals, the sensor core is located at the reference position. Therefore, the stroke of the linear compressor is controlled by the initially set stroke command value. If the signal is LOW, the sensor core 30 is located on the upper side than the reference position, so that the stroke of the linear compressor is compensated by setting the stroke command value less than the initial command value. The large setting compensates for the stroke of the linear compressor. In this case, the HIGH and HIGH signals are not considered because they do not have a sensor core or because they occur in a phenomenon of complete departure.

5 is a control flowchart illustrating a method of controlling a control device of a linear compressor according to an embodiment of the present invention. Referring to FIG. 5, in operation 100, an initial stop position of a sensor core corresponding to an output signal of a first comparator OP1 and a second comparator OP2 is previously set (100). That is, when the initial stop position of the sensor core is a preset position, that is, the reference position, the output signals of the first comparator OP1 and the second comparator OP2 are set to be LOW and LOW, respectively. In addition, when the initial stop position of the sensor core is located farther from the reference position with respect to the zero position, which is the top dead center position, the output signals of the first comparator OP1 and the second comparator OP2 are respectively HIGH and LOW. Set it to On the other hand, if the initial stop position of the sensor core is located closer to the reference position relative to the zero position, the output signal of the first comparator (OP1) and the second comparator (OP2) is set to output LOW, HIGH, respectively.

Then, in step 101, the compressor controller 60 determines whether the linear compressor is in the idle period (101).

As a result of the determination in step 100, if the compressor is in the rest period, the compressor controller 60 turns on the switching circuits S1 to S6 (102).

In operation 103, the compressor controller 60 compares signals output from the first comparator and the second comparator of the initial stop position detection circuit of the position detector.

As a result of the comparison in step 103, if the output signals of the first comparator and the second comparator are HIGH and LOW, respectively, it is determined that the initial stop position of the sensor core is located farther from the reference position as set in step 100 (104). ), The current stroke command value is reset lower to reduce the cooling force due to the initial stop position deviation of the sensor core (105).

If the output signals of the first comparator and the second comparator are OW and LOW, respectively, in step 103, as determined in step 100, it is determined that the initial stop position of the sensor core is located at a preset position (106). ), The current stroke command value is maintained to maintain the currently set cooling force (107).

If the output signal of the first comparator and the second comparator is LOW and HIGH, respectively, in step 103, it is determined that the initial stop position of the sensor core is located closer to the reference position as set in step 100 ( 108), the current stroke command value is reset higher so as to increase the cooling force according to the initial stop position deviation of the sensor core (109).

After the current stroke command value is maintained or increased according to the comparison result in step 103, the switching circuits S1 to S5 are turned off in step 110.

Then, in step 111, the compressor controller 60 determines whether the linear compressor needs to be driven after the idle period of the linear compressor is over (111).

If it is determined in step 111 that the compressor needs to be driven, the compressor controller 60 drives the linear compressor based on the stroke command value held or reset in step 105, 107, or step 109.

As described in detail above, an object of the present invention is to detect the initial stop position of the sensor core, and if the initial stop position of the sensor core is shifted from the reference position, by compensating the stroke deviation according to the sensor by assembly deviation or cumulative deviation, etc. Since the initial stop position of the core is changed, even if the stroke deviation of the linear compressor occurs, the stroke deviation can be compensated, thereby improving the cooling power deviation of the linear compressor.

In addition, the present invention can reduce the number of replacement and disposal of the linear compressor due to poor assembly, poor cooling power, there is an effect that can improve the reliability for the linear compressor.

1 is a block diagram of a general linear compressor.

2 is a control block diagram of a control apparatus of the linear compressor according to the embodiment of the present invention.

3 shows the motion of the sensor core during normal stroke.

4 is a view showing the motion of the sensor core during the stroke of the initial stop position is moved to the upper side.

5 is a control flowchart illustrating a method of controlling a control device of a linear compressor according to an embodiment of the present invention.

* Description of the code for the main functions of the drawings

40: position detection unit 50: digital signal processing circuit

60: compressor control unit 70: compressor driving unit

80: compressor motor

Claims (5)

In the control device of the linear compressor having a piston installed in the compression chamber so as to reciprocate, and a sensor core that operates in conjunction with the piston, A position detector for detecting an initial stop position of the sensor core; A compressor control unit for resetting the stroke of the linear compressor based on the degree to which the initial stop position of the sensor core detected by the position detection unit is out of a preset position; And a compressor driver for driving the linear compressor based on the reset stroke according to the control signal of the controller. The method of claim 1, wherein the position detecting unit is a first coil and the second coil wound symmetrically on the outside of the sensor core, the voltage divider (R11, R13) connected in series between one end and the other end of the first coil, A connection point between the divided resistors R12 and R14 connected in series between one end and the other end of the second coil and the divided resistors R11 and R13 is connected to a non-inverting terminal (+), and the divided resistors R12 and R14 are connected. Is connected to the first comparator (OP1) connected to the inverting terminal (-), the voltage divider (R7, R9) connected in series between one end and the other end of the first coil, and connected in series between one end and the other end of the second coil A connection point between the voltage divider resistors R8 and R10 and the voltage divider resistors R9 and R9 is connected to a non-inverting terminal (+), and a connection point of the voltage divider resistors R8 and R10 is connected to an inverting terminal (−). Control device for a linear compressor, characterized in that it comprises a two comparators (OP2). The method of claim 2, wherein the voltage dividing resistance (R7 ~ R14) value is a predetermined position or the zero position of the sensor core in consideration of the change in inductance of the first coil and the second coil that changes according to the position of the sensor core When the reference position is higher or lower than the preset position, the combination of the output values of the first comparator and the second comparator may be determined so that the relative position of the sensor core can be recognized only by the output values of the first comparator and the second comparator. Control device of a linear compressor, characterized in that preset to be output differently. The apparatus of claim 1, wherein the compressor control unit resets the stroke at every idle period of the linear compressor. 2. The compressor of claim 1, wherein the position detection unit comprises a first detection circuit that detects an initial stop position of the sensor core, and a second detection circuit that detects a position and a stroke amount of the piston, and the compressor control unit comprises: a first detection circuit; The switching circuit selectively switches the power supply to the detection circuit and the second detection circuit so that the power is supplied only to the first detection circuit before the linear compressor is driven, and only the second detection circuit is supplied when the linear compressor is driven. Control device of a linear compressor, characterized in that the loss.