KR100575688B1 - Driving control apparatus for capacity variable type reciprocating compressor - Google Patents

Abstract

The present invention relates to a variable displacement reciprocating compressor, in which two coils and two capacitors having the same winding ratio are connected in series or in parallel according to the operating load of the compressor to vary the capacitance and inductance to perform resonance operation. . To this end, the present invention is the first and second capacitor having the same capacitance; First and second coils having the same turns ratio; First switching means for connecting the first coil and the second coil in series or in parallel by a control signal; Second switching means for connecting the first and second capacitors in parallel by a control signal; And control means for outputting a control signal for controlling the switching operation of the first and second switching means according to the load size of the compressor capacity.

Description

Operation control device for variable displacement reciprocating compressors {DRIVING CONTROL APPARATUS FOR CAPACITY VARIABLE TYPE RECIPROCATING COMPRESSOR}

Figure 1 is a block diagram showing the configuration for the operation control device of a typical reciprocating compressor.

2 is a circuit diagram of an embodiment of an operation control apparatus of a conventional variable displacement reciprocating compressor.

Figure 3 is a circuit diagram of an embodiment of the operation control apparatus of the present invention variable displacement reciprocating compressor.

Figure 4 is a circuit diagram of another embodiment of the operation control apparatus of the present invention variable displacement reciprocating compressor.

Figure 5 is a circuit diagram of another embodiment of the operation control apparatus of the present invention variable displacement reciprocating compressor.

Fig. 6 is an equivalent circuit diagram of a series connection at low load in Fig. 5;

7 is a parallel connection equivalent circuit diagram in the case of overload in FIG.

***** Description of the symbols for the main parts of the drawings *****

A coil, B coil: Coil Ry1, Ry2, Ry3: Relay

C1, C2: Capacitor

The present invention relates to a variable displacement reciprocating compressor, and in particular, two coils and two capacitors having the same winding ratio are connected in series or in parallel according to the operating load of the compressor to vary the capacitance and inductance to perform resonance operation. A variable displacement reciprocating compressor.

In general, the reciprocating compressor has an advantage that it can be used for variable cooling power control by varying the compression ratio as the voltage applied to the motor is variable, refer to the accompanying drawings of the reciprocating compressor. Will be explained.

1 is a block diagram showing a configuration of an operation control apparatus of a general reciprocating compressor. As shown in FIG. 1, a reciprocating compressor in which a piston changes a stroke in vertical motion by adjusting a stroke voltage according to a stroke command value. (L.COMP); A voltage detector 30 which detects a voltage generated in the reciprocating compressor L.COMP as the stroke is increased by the stroke voltage; A current detector 20 which detects a current applied to the reciprocating compressor L.COMP as the stroke is increased by the stroke voltage; A microcomputer (40) for calculating a stroke from the voltage and current detected by the voltage detector (30) and the current detector (20), comparing the stroke with a stroke command value, and outputting a switching control signal accordingly; In accordance with the switching control signal of the microcomputer 40, it is composed of an electric circuit portion 10 for interrupting the AC power to the triac (Tr1) to apply a stroke voltage to the reciprocating compressor (L.COMP), as described above. The operation of the configured conventional device will be described.

First, in the reciprocating compressor L.COMP, the piston is linearly moved by the stroke voltage according to the stroke command value set by the user, whereby the stroke is variable to adjust the cooling force.

On the other hand, the triac Tr1 of the electric circuit unit 10 increases the stroke due to the longer turn-on period due to the switching control signal of the microcomputer 40, and at this time, the voltage generated in the reciprocating compressor L.COMP The current is detected by the voltage detector 30 and the current detector 20, and applied to the microcomputer 40.

Then, the microcomputer 40 calculates a stroke by using the voltage and current detected from the voltage detector 30 and the current detector 20, and compares the stroke with the stroke command value, thereby converting the switching control signal accordingly. Output

That is, when the calculated stroke is smaller than the stroke command value, the microcomputer 40 outputs a switching control signal that lengthens the on-cycle of the triac Tr1 to output the stroke voltage applied to the reciprocating compressor L.COMP. Increase.

Here, in the motor provided in the reciprocating compressor (L.COMP), the coil is wound uniformly at a predetermined turns ratio, and the driving voltage is generated by the stroke voltage to be driven.

Unlike the above, when the calculated stroke is larger than the stroke command value, the microcomputer 40 outputs a switching control signal for shortening the on-cycle of the triac Tr1 and is applied to the reciprocating compressor L.COMP. Reduce stroke voltage.

The reciprocating compressor drive circuit described above has a problem that noise is generated by switching a voltage by a triac and applying it to a motor for stroke control, and an additional circuit for removing the noise is required.

In order to solve this problem, as shown in FIG. 2, the main coil and the sub coil are optimized to change the capacity by changing the number of turns of the coil by itself to cope with load and voltage fluctuations. Drive with efficiency.

In the motor M of the reciprocating compressor as shown in FIG. 2, the coil wound around the main coil is divided into a main coil and a sub coil, and according to a voltage change and a load change, a main coil The main coil is selected as the motor coil, or the main coil and the sub coil are selected as the motor coils to alter the capacity of the motor.

In other words, when the current load is greater than the reference load (overload), the relay electromotive force constant of the motor is reduced by switching only the contact of the relay Ry to the ① contact and selecting only the main coil as the motor coil.

Accordingly, when commercial power is applied, the input current and the stroke are increased to increase the cooling power.

On the contrary, when the current load is smaller than the reference load (low load), by switching the contact point of the relay Ry to contact point ③ and using both the main coil and the sub coil as the motor coil, Increase the back EMF constant of the motor

Accordingly, when commercial power is applied, the input current and the stroke are reduced to reduce the cooling power.

That is, since the winding number N of the coil wound on the motor M of the reciprocating compressor has a proportional relationship with the motor back EMF constant, when the constant input voltage is applied, the number of turns N of the stroke and the coil is in inverse proportion. Expressed as

Therefore, in order to vary the motor capacity by using the above characteristics, the number of windings N of the coil is driven by the relay driving control signal of the microcomputer 200 in accordance with the input power and the load to drive the motor Ry. The stroke voltage is varied by itself.

However, the above-mentioned capacitively variable reciprocating compressor uses a resonant capacitor in common under overload or underload. However, the resonant operation becomes difficult when the number of turns of the coil, i.e., the difference in coil inductance is large in both cases. There is a problem that the system is incompletely operated.

In addition, during overload operation, since the sub coil is not used, efficient use of the coil is difficult, and the copper wire of the main coil is increased to increase the coil resistance, thereby increasing the loss due to motor heating.

The present invention has been made to solve the above problems, by connecting two coils and two capacitors having the same turns ratio, in series or parallel according to the operating load of the compressor to vary the capacitance and inductance to resonate operation It is an object of the present invention to provide an operation control device for a variable displacement reciprocating compressor.

According to an aspect of the present invention, there is provided a reciprocating compressor operating at a resonance frequency of a capacitor and a coil, the first and second capacitors having the same capacitance; First and second coils having the same turns ratio; First switching means for connecting the first coil and the second coil in series or in parallel by a control signal; Second switching means for connecting the first and second capacitors in parallel by a control signal; And control means for outputting a control signal for controlling the switching operation of the first and second switching means according to the load size of the compressor capacity.

According to an aspect of the present invention, there is provided a reciprocating compressor operating at a resonance frequency of a capacitor and a coil, the first and second capacitors having the same capacitance; First and second coils having the same turns ratio; Switching means for connecting the first coil and the second coil, the first capacitor and the second capacitor in series or in parallel by a control signal; And control means for outputting a control signal for controlling the switching operation of the switching means according to the load size of the compressor capacity.

The present invention for achieving the above object, In the reciprocating compressor, First and second coil having the same turns ratio; Switching means for connecting the first coil and the second coil in series or in parallel by a control signal; According to the load size of the compressor capacity, it characterized in that it comprises a control means for outputting a control signal for controlling the switching operation of the switching means.

Hereinafter, with reference to the accompanying drawings, the operation and effect of the operation control device of the variable displacement reciprocating compressor according to the present invention will be described in detail.

Figure 3 is a circuit diagram showing the configuration of an embodiment of the operation control device of the variable displacement reciprocating compressor of the present invention.

3, first and second capacitors having the same capacitance; First and second coils (A coils) having the same turns ratio; First and second relays Ry1 and Ry2 for connecting the first coil A and the second coil B in series or in parallel by a control signal; A third relay Ry3 connecting the first and second capacitors C1 and C2 in parallel by a control signal; According to the load size of the compressor capacity, the control signal for controlling the switching operation of the first, second, third relays (Ry1, Ry2, Ry3) is output and the switching of the triac (not shown) is controlled. It comprises a control means (not shown).

The first and second coils (B coils) connect the front end of the first coil (A coil) and the rear end of the second coil (B coil) through a first relay (bridge 1). The connection point of the rear end of a 1st coil A and the front end of a 2nd coil B coil is connected to a power supply terminal via a 2nd relay (bridge 2).

Such operation of the present invention will be described.

First, the control means (not shown), by experiment, the reference load as a reference for selecting the first, second coil (A coil) (B coil) and the first, second capacitors (C1, C2) And a memory (not shown) which is preset and stored.

In this state, the control means (not shown) compares the user's desired temperature with the present temperature, and detects the load based on the comparison result.

At this time, a load corresponding to the desired temperature and the present temperature is preset by experiment.

The control means (not shown) compares the detected load with a reference load previously stored in a memory (not shown), and outputs a control signal for varying the capacity of the compressor based on the comparison result.

That is, when the capacity load of the compressor is smaller than the reference load, the control means (not shown) recognizes the low load, turns off the first relay Ry1 as shown in FIG. By connecting the relay Ry2 to the contact ②, the first and second coils A are connected in series to be selected as a motor coil, thereby increasing the counter electromotive force constant of the motor and at the same time, the third relay Ry3. Is controlled to connect only the capacitor C2.

Accordingly, when a commercial power source is applied, the output current can be reduced by efficiently reducing the input current and the stroke.

On the other hand, when the capacity load of the compressor is greater than the reference load, the control means (not shown) recognizes as an overload, and connects the first and second coils (A coil) in parallel, The first and second capacitors C1 and C2 are connected in parallel to increase the capacitance. As shown in FIG. 3A, the first relay Ry1 is turned on and the second relay Ry2 is contacted. By switching to ①, the back EMF constant of the motor is made small. At this time, by turning on the third relay Ry3, two capacitors C1 and C2 are connected in parallel to perform LC resonance operation.

Accordingly, when a commercial power source is applied, the output can be increased by stably increasing the input current and the stroke.

Figure 4 is a circuit diagram showing the configuration of another embodiment of the operation control apparatus of the present invention variable displacement reciprocating compressor.

As shown in Fig. 4, the present invention includes: first and second capacitors C1 and C2 having the same capacitance; First and second coils (A coils) having the same turns ratio; Switching means (Ry1, Ry2) for connecting the first and second coils (B coil) and the first and second capacitors (C1, C2) in series or in parallel by a control signal; According to the load size of the compressor capacity, and outputs a control signal for controlling the switching operation of the switching means (Ry1, Ry2), and includes a control means (not shown) for controlling the switching of the triac (not shown) The operation of the present invention will be described.

First, the control means (not shown), by experiment, the reference load as a reference for selecting the first, second coil (A coil) (B coil) and the first, second capacitors (C1, C2) And a memory (not shown) which is preset and stored.

In this state, the control means (not shown) compares the user's desired temperature with the present temperature, and detects the load based on the comparison result.

At this time, a load corresponding to the desired temperature and the present temperature is preset by experiment.

The control means (not shown) compares the detected load with a reference load previously stored in a memory (not shown), and outputs a control signal for varying the capacity of the compressor based on the comparison result.

When the capacity load of the compressor is smaller than the reference load, the control means (not shown) recognizes as a low load, and connects the contact ① and the contact ③ of the switching means Ry1 as shown in FIG. By connecting the first and second coils (A coils) in series and selecting them as motor coils, the counter electromotive force constant of the motor is increased. That is, when the capacity load of the compressor is smaller than the reference load, the first capacitor The first coil A connected to C1 and the second coil B coil connected to the second capacitor C2 at the front end are connected in series.

In this case, the first and second capacitors C1 and C2 are connected to the first and second coils B, respectively, so that resonance may occur, thereby significantly reducing the phase difference between the currents flowing through the two coils. have.

Accordingly, when a commercial power source is applied, the output current can be reduced by efficiently reducing the input current and the stroke.

On the other hand, the control means (not shown), when the capacity load of the compressor is greater than the reference load, it is recognized as an overload, and controls to connect the first coil (A coil) (B coil) in parallel 4, the contact ① and the contact ④ of the switching means Ry2 are connected, and the contact ③ and the contact ⑤ are connected to reduce the counter electromotive force constant of the motor, and further, the first and second coils. (A coil) (B coil) performs LC resonant operation with capacitors C1 and C2 connected to one side, respectively.

That is, the control means (not shown), if the capacity load of the compressor is greater than the reference load, the control means (not shown) in front of the first capacitor (C1) and the second coil (B coil) connected to the front end of the first coil (A coil) By connecting the connected second capacitor C2 and controlling the rear ends of the first and second capacitors C1 and C2 to be connected to each other, the amount of each current flowing in the two coils B coils is increased. The loss is significantly reduced.

However, the present invention described above has a problem in that a manufacturing cost increases as a capacitor is used as a whole, and a high voltage is applied to the triac to damage the triac in the process of canceling back electromotive force applied to the capacitor.

Therefore, in another embodiment of the present invention, by removing the capacitor and configured as shown in Figure 5, the manufacturing cost is reduced, the operation principle of Figure 5 is the same as Figures 3 and 4.

That is, the control means (not shown), when the capacity load of the compressor is less than the reference load, the first relay Ry1 so that the first coil (A coil) and the second coil (B coil) are connected in series. Connect to the 'L' terminal and control to turn off the second relay (Ry2).

If the capacity load of the compressor is greater than the reference load, the first relay Ry1 is connected to the 'H' terminal and the second relay is connected so that the first coil A and the second coil B are connected in parallel. Control to turn on (Ry2).

6 is an equivalent circuit diagram of a series connection at low load, and FIG. 7 is an equivalent circuit diagram of a parallel connection at overload.

In this case, the memory (not shown) sets and stores a reference load as a reference for selecting the first and second coils by experiment.

In the event of an overload, two coils are connected in parallel to flow current to each coil to reduce the amount of heat generated from the coil windings, thereby improving the reliability of the winding coils, and connecting the two coils in series. When applied, output can be reduced by efficiently reducing input current and stroke.

The specific embodiments or examples made in the detailed description of the present invention are intended to clarify the technical contents of the present invention to the extent that they should not be construed as limited to these specific embodiments and should not be construed in consultation. Various changes can be made within the scope of.

As described in detail above, in the present invention, two coils and two capacitors having the same turns ratio are connected in series or in parallel according to the operating load of the compressor to vary the capacitance and inductance, thereby resonantly operating the system. It is effective to drive.

In addition, by eliminating the capacitor and using only two coils having the same turns ratio, the inductance is varied by operating in series or parallel according to the operating load of the compressor. have.

Claims (16)

In a reciprocating compressor operating at the resonance frequency of a capacitor and a coil, First and second capacitors having the same capacitance; First and second coils having the same turns ratio; First switching means for connecting the first coil and the second coil in series or in parallel by a control signal; Second switching means for connecting the first and second capacitors in parallel by a control signal; And a control means for outputting a control signal for controlling the switching operation of the first and second switching means, in accordance with the load size of the compressor capacity. The method of claim 1, wherein the control means, When the capacity load of the compressor is less than the reference load, the operation control device of the variable displacement reciprocating compressor characterized in that the control to connect the first and second coils in series. The method of claim 1, wherein the control means, When the capacity load of the compressor is greater than the reference load, the operation control device of the variable displacement reciprocating compressor characterized in that the control to connect the first and second coils in parallel. The method of claim 1, wherein the control means, When the capacity load of the compressor is smaller than the reference load, the operation control device of a variable displacement reciprocating compressor characterized in that the control to connect only one of the first capacitor or the second capacitor. The method of claim 1, wherein the control means, When the capacity load of the compressor is greater than the reference load, the operation control device of the variable displacement reciprocating compressor characterized in that the control to connect the first capacitor and the second capacitor in parallel. The method of claim 1, wherein the first and second capacitors, Operation control apparatus of a variable displacement reciprocating compressor characterized in that connected in parallel to each other via a relay. The method of claim 1, wherein the first and second coils, The front end of the first coil and the rear end of the second coil are connected via the first relay, And a connection point between the rear end of the first coil and the front end of the second coil is connected to the entire far end through a second relay. The variable displacement reciprocating device of claim 1, further comprising a memory configured to store, by experiment, a reference load that is a reference for selecting the first and second coils and the first and second capacitors. Operation control device of same type compressor. In a reciprocating compressor operating at the resonance frequency of a capacitor and a coil, First and second capacitors having the same capacitance; First and second coils having the same turns ratio; Switching means for connecting the first coil and the second coil, the first capacitor and the second capacitor in series or in parallel by a control signal; And a control means for outputting a control signal for controlling the switching operation of the switching means, in accordance with the load size of the compressor capacity. The method of claim 9, wherein the control means, When the capacity load of the compressor is smaller than the reference load, the variable displacement reciprocating compressor characterized in that the first coil connected to the first capacitor connected to the front end, and the second coil connected to the second capacitor connected to the front end connected in series Operation control device. The method of claim 9, wherein the control means, If the capacity load of the compressor is greater than the reference load, the first capacitor connected to the front end of the first coil and the second capacitor connected to the front end of the second coil are connected. And controlling the rear ends of the first and second capacitors to be connected to each other. 10. The variable displacement reciprocating device of claim 9, further comprising a memory configured to, by experiment, preset and store a reference load as a reference for selecting the first and second coils and the first and second capacitors. Operation control device of same type compressor. In a reciprocating compressor, First and second coils having the same turns ratio; Switching means for connecting the first coil and the second coil in series or in parallel by a control signal; And a control means for outputting a control signal for controlling the switching operation of the switching means, in accordance with the load size of the compressor capacity. The method of claim 13, wherein the control means, And if the capacity load of the compressor is smaller than the reference load, the first and second coils are connected in series to control the operation of the capacity variable reciprocating compressor. The method of claim 13, wherein the control means, If the capacity load of the compressor is greater than the reference load, the operation control device of the variable displacement reciprocating compressor characterized in that the control to connect the first coil and the second coil in parallel. 14. The operation control apparatus for a variable displacement reciprocating compressor according to claim 13, further comprising a memory for presetting and storing a reference load serving as a reference for selecting the first and second coils by experiment.

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