CN1258664C - Control method of one-driving-several air conditioner - Google Patents

Abstract

The present invention relates to a control method of a one-to-many air conditioner in the field of air conditioners. Various temperature sensors are arranged in the proper position of a refrigeration system of the air conditioner, signals which are detected are input into a preset control and regulating system, and after the signals are processed, the signals are output so as to control a compressor in the refrigeration system, a plurality of electronic expansion valves of indoor machines, etc. The present invention achieves the aim of control. The present invention adopts an integral scheme to solve the problem of the control of the compressor and the electronic expansion valves in the refrigeration system, and simultaneously, the control function of an outdoor machine is strengthened. A control system in the outdoor machine is used for finishing the control of the entire system, and therefore, the present invention has the advantages of high reliability and convenient repair.

Description

One drags the control method of many air-conditionings

Technical field

The present invention relates to field of air conditioning, more particularly, relate to a kind of be applied to residential central air conditioner unit (residential central air-) and convertible frequency air-conditioner control field, a control method of dragging many air-conditionings.

Background technology

Present field of air conditioning, aspect relevant compressor, the evaporation degree of superheat, electronic expansion valve opening, room temperature, the return-air degree of superheat, pressure at expulsion, back pressure or the like control, do not form a cover and be fit to above control model various controlled quentity controlled variables, that have the dynamic compensation correction, relatively more chaotic.As aspect the compressor control, generally regulate the operating frequency of frequency-changeable compressor by the difference variation between user's design temperature and the room actual temperature, give different proportionality coefficients according to different temperature difference ranks, reach the purpose of adjusting the compressor operation frequency.And aspect electronic expansion valve controls, substantially do not form unified, ripe control scheme at present, the evaporating temperature according to refrigerant that has is regulated its aperture, some regulates aperture according to the deviation of evaporator refrigerant temperature and design temperature, is in addition to control aperture by the degree of superheat of heat exchanger inlet and outlet refrigerant in the control room; Method is varied.

Drag many small central air conditionings field one, owing to have many indoor sets, the controlled quentity controlled variable that relates to is many, and the control complexity is big, does not also have ripe control scheme at present.

In addition, the control of compressor is a sets of plan, and electronic Expansion Valve Control is again a sets of plan, even the control of back pressure is again a sets of plan, or the like these certainly will cause the control scheme too complicated, occur the phenomenon of attending to one thing and lose sight of another easily, drag many control field one especially, tool two compressors, its control method is different fully, the control target temperature difference of many indoor sets, controlled quentity controlled variable is many, easier going wrong.

Summary of the invention

The technical problem to be solved in the present invention is, at the above-mentioned defective of prior art, provides a kind of one control method of dragging many air-conditionings, drags compressor and electronic Expansion Valve Control problem in many air-conditionings by the scheme solution one of an integral body.

The all temps sensor of the present invention by installing in the appropriate location of air-conditioning refrigeration system, detected signal is input to pre-set control and regulation system, output after treatment, be used for controlling the mechanisms such as electric expansion valve of compressor and each indoor set of refrigeration system, reach the purpose of control.

Be used for dragging the control method of many air-conditionings among the present invention, may further comprise the steps:

(1), according to the indoor temperature T of reality _r, user's design temperature T _sAnd actual indoor-unit cooling-medium temperature T _n, calculate actual indoor-unit cooling-medium temperature T _nWith target refrigerant temperature T _N-setBetween refrigerant temperature difference Δ T _n

(2), according to the indoor-unit cooling-medium temperature T of reality _n, off-premises station refrigerant temperature T _g, outdoor temperature T _a, the total operating frequency Hz of compressor and actual compressor exhaust temperature T _b, calculate actual compressor exhaust temperature T _bWith target exhaust temperature T _kBetween delivery temperature difference Δ T _b

(3), by a multivariable controller according to described refrigerant temperature difference Δ T _nWith delivery temperature difference Δ T _bCalculate the variation delta Ev of expansion valve opening Ev and the variation delta Hz of operating frequency Hz,, control expansion valve and compressor respectively according to described Δ Ev and Δ Hz; Wherein, described expansion valve opening variation delta Ev is directly outputed to electric expansion valve to control its aperture; The variation delta Hz of described compressor operation frequency is input to a double-compressor running ability Distribution Calculation device, calculates two compressors running ability code N1, N2 separately to control two compressors by described capability distribution calculator.

According to method of the present invention, in described (3) step, earlier by a deviation compensator to described refrigerant temperature difference Δ T _nCompensate, with delivery temperature difference Δ T _bWith the refrigerant temperature difference Δ T after the compensation _n' be input to described multivariable controller simultaneously; Then by the dynamic model in the described multivariable controller according to described refrigerant temperature difference Δ T _n' and delivery temperature difference Δ T _bCalculate expansion valve opening variation delta Ev and operating frequency variation delta Hz, be respectively applied for control expansion valve and compressor.

According to method of the present invention, in described (3) step, earlier by a deviation compensator simultaneously to described refrigerant temperature difference Δ T _nWith delivery temperature difference Δ T _bCompensate, with the Δ T after the compensation _n' and Δ T _b' be input to described multivariable controller simultaneously; Then by the Δ T of the dynamic model in the described multivariable controller after according to described compensation _n' and Δ T _b' calculate expansion valve opening variation delta Ev and operating frequency variation delta Hz, be respectively applied for control expansion valve and compressor.

According to method of the present invention, in described (3) step, earlier by the dynamic model in the described multivariable controller according to described refrigerant temperature difference Δ T _nWith delivery temperature difference Δ T _bCalculate expansion valve opening variation delta Ev and operating frequency variation delta Hz; Again described Δ Ev and Δ Hz are input to a deviation compensator and compensate, draw aperture variation delta Ev ' and operating frequency variation delta Hz ' after the compensation, be respectively applied for control expansion valve and compressor.

Control method of the present invention designs solution with employings such as intrasystem compressor, electric expansion valve one cover dynamic deviation compensation method, reach and control effect preferably, the penalty coefficient of system can be adjusted automatically according to the operation of a machine state in the control, and the dynamic model of control can be selected for use arbitrarily.The capability distribution scheme that adopts solves the running ability assignment problem of double-compressor.

Description of drawings

Fig. 1 is the refrigerant system configurations schematic diagram that double-compressor one drags many air-conditionings;

Fig. 2 is the schematic diagram of control system major part in the embodiment of the invention one;

Fig. 3,4, the 5th, the control flow chart of control system in the embodiment of the invention one;

Fig. 6 is the schematic diagram of control system major part in the embodiment of the invention two;

Fig. 7, the 8th, the control flow chart of control system in the embodiment of the invention two;

Fig. 9 is the schematic diagram of control system major part in the embodiment of the invention three;

Figure 10, the 11st, the control flow chart of control system in the embodiment of the invention three.

The specific embodiment

One, refrigeration system constitutes

Among the present invention, the formation of multi-split air conditioner comprises outdoor unit and indoor unit as shown in Figure 1.

Wherein, outdoor unit is mainly by variable displacement compressor 101, and constant volume compressor 102, cross valve 107, outdoor heat converter 108, indoor and outdoor machine electric expansion valve 111,118, high-low pressure reservoir 112,113, lubricating oil are handled pipeline etc. and partly formed.

When cooling condition, the refrigerant sequence of flow is as follows, and forms the closed loop refrigerating circuit:

Compressor 101,102 → oil eliminator 103,104 → check valve, 122 → cross valve, 107 → outdoor heat converter 108 → outdoor electric expansion valve 111 → high pressure reservoir 112 → indoor electric expansion valve 118 → indoor heat converter 119 → cross valve 107 → low-pressure oil storage 113 → compressor 101,102.

When heating condition, the sequence of flow of refrigerant is as follows, and the formation closed loop heats the loop:

Compressor 101,102 → oil eliminator 103,104 → check valve, 122 → cross valve, 107 → indoor heat converter 119 → indoor electric expansion valve 118 → high pressure reservoir 112 → outdoor electric expansion valve 111 → outdoor heat converter 108 → cross valve 107 → low-pressure oil storage 113 → compressor 101,102.

As seen this air-conditioning system has adopted two high performance compressors, one is the variable compressor of ability 101, and another is the compressor 102 of power surely, in the operation process, different abilities by two compressors make up the energy output that realizes different energy levels, satisfy the needs of indoor ability.

As can be seen from Figure 1, in the outdoor unit of above-mentioned refrigeration system, between check valve 122 and cross valve 107, exhaust gas temperature sensor 105 is housed, is used to detect the delivery temperature T of compressor 101,102 _bBetween low-pressure oil storage 113 and compressor 101,102, suction temperature sensor 115 is housed, is used to detect the suction temperature of compressor 101,102; Air suction inlet at outdoor heat converter 108 is equipped with outdoor temperature sensor 110, is used to detect the operating ambient temperature T of off-premises station _aOutdoor refrigerant temperature sensor 109 is housed in outdoor heat converter 108, is used for the temperature T of testing refrigerant _g(can be evaporating temperature or condensation temperature); Between check valve 122 and cross valve 107, back pressure transducer 106 is housed, is used to detect the pressure at expulsion of compressor 101,102; Back pressure sensor 114 is housed between low-pressure oil storage 113 and compressor, is used to detect the back pressure of compressor 101,102.

In the indoor unit of above-mentioned refrigeration system, in the air inlet of indoor heat converter 119 indoor temperature transmitter 120 is housed, be used for detecting the temperature T of indoor set place environment _rIndoor refrigerant temperature sensor 121 also is housed in indoor heat converter 119, is used for the refrigerant temperature T of testing _n

As can be seen from Figure 1, between two compressors 101,102, oil balance tube 116 is housed also, is used for the lubricating oil between balance two compressors.The effect of oil eliminator 103,104 is to separate the lubricating oil of taking out of with compressor air-discharging, and sends lubricating oil back to separately compressor by special pipeline.

Two, control system constitutes

In control system, major part such as Fig. 2 of controller constitute, and record various parameters in the operation of air conditioner, as outdoor environment temperature T _a, indoor environment temperature T _rDeng, all be input in the controller, through after the calculation process of controller, at last as compressor operation frequency Hz, the output of electronic expansion valve opening Ev signal pulse, be used for controlling compressor and electric expansion valve, meaning of parameters, control algolithm in its control procedure and the process will be described below.

1, the course of work

1-1, according to user's design temperature T _sWith by the measured indoor temperature T of indoor temperature transmitter 120 _r, calculate between the two temperature difference Δ T by adder 10 _rBy target evaporation/condensation temperature calculator 11, calculate target refrigerant temperature T again _N-setCalculate T through adder 13 again _N-setWith by indoor refrigerant temperature sensor 121 measured indoor refrigerant temperature T _nBetween difference DELTA T _n(can be evaporating temperature Δ T _eOr condensation temperature Δ T _c), output in the deviation compensator 15.

1-2, on the other hand is according to detected outdoor environment temperature T _a, outdoor heat converter refrigerant temperature T _g, indoor heat converter refrigerant temperature T _nAnd the operating frequency Hz of compressor, calculate the target exhaust temperature T of compressor by target exhaust temperature calculator 12 _k, calculate the target exhaust temperature T of compressors again through adder 14 _kWith the actual exhaust air temperature T _bBetween difference DELTA T _b, output to deviation compensator 15.

1-3, deviation compensator 15 are according to the Δ T that imports _nWith Δ T _b, penalty coefficient is defined as the linear function of compressor operation frequency, calculate function, the deviation delta T after being compensated _n' (can be evaporating temperature Δ T _e' or condensation temperature Δ T _c') and Δ T _b', output to multivariable controller 16 again.

1-4, multivariable controller 16 are according to the Δ T that is imported _n' and Δ T _b', calculate the changing value Δ Ev and the frequency change value Δ Hz of expansion valve opening according to pre-set dynamic model, at last to electric expansion valve output Ev, to double-compressor running ability calculator 17 output frequency Hz.

1-5, double-compressor running ability calculator 17 calculate the code of the running ability separately N of two compressors according to the total operating frequency Hz that is imported according to the capability distribution computing formula of compiling and editing in advance ₁, N ₂, and send running to two compressors and instruct, compressor is turned round according to pre-provisioning request.

In above-mentioned steps: T _sFor setting indoor temperature, T _aBe outdoor temperature, T _rBe indoor temperature, T _bBe compressor exhaust temperature, T _gBe off-premises station refrigerant temperature, T _nBe indoor-unit cooling-medium temperature, T _kBe the compressor target exhaust temperature, Hz is the total operating frequency of compressor, E _vBe expansion valve opening, N ₁Be variable displacement compressor energy code, N ₂Be constant volume compressor energy code.

2, the calculating of algorithm-compensation

2-1, target exhaust temperature are calculated by following formula:

T _K=A * T _C+ B * T _e+ C * Hz ²+ D * Hz+E * T _aFormula 1 wherein A, B, C, D, E is a constant, T _CBe the condensation temperature of refrigerant, T _eEvaporating temperature for refrigerant.

The calculating of 2-2, target evaporating temperature

When 2-2-1, refrigeration:

$T_{n-\mathrm{set}}=T_{n-\mathrm{set}}+{\mathrm{<figure-callout\; id="1"\; label="K\; P"\; filenames="C0211474900213.png"\; state="\{\{state\}\}">K</figure-callout>}}_P\&times;(\mathrm{\&Delta;}{T}_r-\mathrm{\&Delta;}{T}_{r-1}+\frac{\mathrm{\&Delta;}{T}_r+{\mathrm{\&Delta;T}}_{r-1}}{2K_{i1}})$ Formula 2

Wherein, K _P1, K _I1Be constant, Δ T _rBe the room temperature deviation, Δ T _R-1Room temperature deviation for the last time sampling.

2-2-2, when heating:

$T_{n-\mathrm{set}}=T_{n-\mathrm{set}}+K_{P2}\&times;(\mathrm{\&Delta;}{T}_r-\mathrm{\&Delta;}{T}_{r-1}+\frac{\mathrm{\&Delta;}{T}_r+{\mathrm{\&Delta;T}}_{r-1}}{2K_{i2}})$ Formula 3

Wherein, K _P2, K _I2Be constant.

The compensation temperature difference is calculated when 2-3, refrigeration

ΔTe’＝ΔTe×(a×Hz+b)

Formula 4, formula 5

Δ T _b'=Δ T _b* (c * Hz+d) wherein, a, b, c, d are constant, and Δ Te is the evaporating temperature deviation, and Δ Te ' is the evaporating temperature deviation after compensating.

2-4, compensation temperature difference calculating when heating

ΔTc’＝ΔTc×(e×Hz+f)

Formula 6, formula 7

ΔT _b’＝ΔT _b×(g×Hz+h)

Wherein, e, f, g, h are constant, and Δ Tc is the condensation temperature deviation, the condensation temperature deviation after the Δ Tc ' compensation.

Constant a-h in the above-mentioned algorithm will set according to test, makes that when pilot system was moved under according to the standard state that configures, every penalty coefficient was 1, promptly under this state, and above-mentioned deviation delta T _n(Δ T _eOr Δ T _c), Δ T _bWith the deviation delta T after the compensation _n' (Δ T _e' and Δ T _c'), Δ T _b' be identical.

In above discussion, penalty coefficient is set at linear function, but the form of function is not limited to linear function, and any type of function can.In addition, controlled quentity controlled variable also is not limited only to the aperture of the operating frequency and the electric expansion valve of compressor, as long as can reflect the value or the amount of operation of air conditioner state, all can be used as the variable of function.As the amount of the operating condition that can reflect air-conditioning, can consider following several: the refrigerant degree of supercooling (degree of superheat) of exhaust (return-air) pressure of the environment temperature of exhaust (return-air) temperature of the evaporation of refrigerant (condensation) temperature, compressor, the environment temperature of indoor set, off-premises station, evaporation (condensation) pressure of refrigerant, compressor, air conditioner load, heat exchanger outlet etc.

3, the calculating of algorithm-controlled quentity controlled variable

Multivariable controller 16 is according to the dynamic model of setting and the deviation delta T that is imported by deviation compensator _b', Δ T _n' (Δ T _e' Δ T _C'), calculate Δ Ev and Δ Hz, finally to compressor and electric expansion valve output signal Hz and Ev.

During refrigeration:

$Z=A_1\&times;Z_P+{\mathrm{<figure-callout\; id="1"\; label="B"\; filenames="C0211474900213.png"\; state="\{\{state\}\}">B</figure-callout>}}_1\&times;\left[\frac{\mathrm{\&Delta;}{T_e}^{\&prime;}}{\mathrm{\&Delta;}{T_b}^{\&prime;}}\right]$ Formula 8

$\left[\frac{\mathrm{\&Delta;Hz}}{\mathrm{\&Delta;Ev}}\right]={\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="C0211474900213.png"\; state="\{\{state\}\}">C</figure-callout>}}_1\&times;(Z-Z_P)$ Formula 9

Wherein, A ₁, B ₁, C ₁The control parameter square of using during for refrigeration is old, Δ T _e' be the evaporating temperature deviation behind the deviation compensation, Δ T _b' be the delivery temperature deviation behind the deviation compensation, Δ Hz is the frequency regulating amount of compressor operation, and Δ Ev is the aperture regulated quantity of electric expansion valve, and Z is the state vector of controller, Z _PThe state vector of the controller when taking a sample for the last time.

When heating

$Z=A_2\&times;Z_P+B_2\&times;\left[\frac{{{\mathrm{\&Delta;T}}_c}^{\&prime;}}{\mathrm{\&Delta;}{T_b}^{\&prime;}}\right]$ Formula 10

$\left[\frac{\mathrm{\&Delta;Hz}}{\mathrm{\&Delta;Ev}}\right]=C_2\&times;(Z-Z_P)$ Formula 11

Wherein, A ₂, B ₂, C ₂The control parameter square of using when heating is old, Δ T _c' be the condensation temperature deviation behind the deviation compensation.

By the way, control Hz and E _v, make compressor exhaust temperature T _bMove closer to compressor target exhaust temperature T _K, the indoor-unit cooling-medium temperature T _nMove closer to indoor-unit cooling-medium target temperature T _N-set

Below the control procedure of the embodiment of the invention one middle controller will be described according to the control flow chart shown in Fig. 3 to Fig. 5.

At first, shown in Figure 3 as flow process, operation of air conditioner begins, carry out initializing set in step 301, move to step 302 after initializing set finishes, to indoor control clock-reset and begin, move to step 303 thereafter, startup subroutine carries out the running of compressor, moves to step 304 after the control indoor temperature, judges whether room temperature control clock is overtime.If not overtime, then move to step 305, wait is determined to get back to step 304 after the time, carries out above-mentioned judgement again, if the room temperature control time is overtime, then gets back to 302, moves to step 303 after indoor clock is resetted, starts and carries out indoor temperature T _rControl, in the real-world operation process, will repeat this action.

The subprogram control action of above-mentioned steps 303 is described according to flow chart 4 below.At first, judge whether to require to carry out cooling operation in step 402 at detected signals such as step 401 input exhaust gas temperature sensor, temperature sensor, indoor heat converter sensors.

If require to carry out cooling operation, then move to step 403 from step 402, calculate target exhaust temperature T _kAnd target evaporating temperature T _N-etBe that calculator 11 and 12 among Fig. 2 carries out correlation computations respectively.

Move to step 404 subsequently, calculate target exhaust temperature T by adder 14 _kWith the detected actual exhaust air temperature T of Tail Pipe Temperature sensor _bBetween deviation delta T _bSimultaneously, calculate target evaporating temperature and the detected actual evaporator refrigerant temperature T of indoor heat converter refrigerant temperature sensor by adder 13 _nBetween difference DELTA T _n

Then to step 405, deviation compensator 15 is according to pre-set formula, the Δ T that imports according to two adders _bWith Δ T _n, be multiplied by the penalty coefficient that the operating frequency Hz according to compressor calculates (a * Hz+b, c * Hz+d), the deviation delta T after being compensated _b' and Δ T _n'.

Continue to move to step 406, the dynamic model of being represented according to formula by multivariable controller 16 is according to the deviation delta T after the compensation of being imported _b' and Δ T _n', calculate the operating frequency Δ Hz of compressor and the controlled quentity controlled variable Δ Ev of electronic expansion valve opening.Move to step 407 then, to double-compressor running ability Distribution Calculation device 17 output sum frequency signal delta Hz, double-compressor running ability Distribution Calculation device is according to the sum frequency change amount signal Δ Hz that is imported, in conjunction with the duty of current two compressors, dispensed arrives the energy force signal N of compressor separately ₁, N ₂

Move to step 408, according to the energy force signal N of compressor separately that is assigned to that calculates ₁, N ₂, send the driving instruction to two compressors, corresponding ability is exported in the running of drive compression machine.Export the control variables Δ Ev of aperture simultaneously to the electric expansion valve of correspondence, after being finished, control program turns back on the main program, by carrying out above step repeatedly, reaches the control cooling operation.

In addition, in flow process shown in Figure 4, be that the judged result of above-mentioned steps 402 is N0 when heating running when what require, the control step jumps to the step 501 of flow chart 5, and similar with above-mentioned steps 403, the calculated signals of gathering according to sensor target exhaust temperature T _kAnd target refrigerant condensation temperature T _N-set

Then to step 502, adder 14 is calculated target exhaust temperature T _kWith the detected actual exhaust air temperature T of Tail Pipe Temperature sensor _bDeviation delta T _bSimultaneously, adder 13 is calculated target condensation temperature and the detected actual refrigerant condensation temperature T of indoor heat converter refrigerant temperature sensor _cDifference DELTA T _c

Step 503 is calculated the deviation delta T after compensating _b' and Δ T _c'.

Move to step 504, similar with step 406, multivariable controller 16 is according to the deviation delta T after the compensation of being imported _b' and Δ T _n', calculate the total operating frequency Δ Hz of compressor and the controlled quentity controlled variable Δ Ev of electronic expansion valve opening.Move to step 505 then, Δ Hz according to input, change signal delta Hz to double-compressor running ability Distribution Calculation device output sum frequency, double-compressor running ability Distribution Calculation device is according to the sum frequency change amount signal Δ Hz that is imported, in conjunction with the duty of current two compressors, dispensed arrives the energy force signal N of compressor separately ₁, N ₂

Step 506, similar to step 408, according to the energy force signal N of compressor separately that is assigned to that calculates ₁, N ₂, send the driving instruction to two compressors, corresponding ability is exported in the running of drive compression machine, exports the control variables Δ Ev of aperture simultaneously to the electric expansion valve of correspondence.After being finished, control program turns back on the main program, equally by carrying out above step repeatedly, reach heating running.

Below the control procedure of the embodiment of the invention two middle controllers will be described according to Fig. 6 to Fig. 8.

As can be seen from Figure 6, in embodiment two, its deviation compensator 15 is located at after the multivariable controller 16, to multivariable controller according to target variable T _e, T _kThe control variables that calculates compensates, and is identical among other parts in addition and the embodiment one.

Concrete implementation such as flow chart 3, Fig. 7 and shown in Figure 8 that is to say that its main flow and embodiment one are identical, and two sub-processes and embodiment one have any different.Fig. 7 and Fig. 4 are contrasted as can be seen, step 701,702,703,704,707,708 respectively with Fig. 4 in 401,402,403,404,407,408 identical, difference is to calculate Δ Hz, Δ Ev by multivariable controller earlier in the step 705, tastes unit 15 to step 706 by the deviation benefit again and calculates Δ Hz ', Δ Ev '.

Equally, Fig. 8 and Fig. 5 are contrasted as can be seen, step 801,802,805,806 respectively with Fig. 4 in 501,502,505,506 identical, difference is to calculate Δ Hz, Δ Ev by multivariable controller earlier in the step 803, tastes unit 15 to step 804 by the deviation benefit again and calculates Δ Hz ', Δ Ev '.

Below the control procedure of the embodiment of the invention three middle controllers will be described according to Fig. 9 to Figure 11.

As can be seen from Figure 9, in the embodiment of the invention three, changed the operating characteristic of deviation compensator 15, with two deviation delta T of compensation among the embodiment one _bWith Δ T _nCompare, herein the indoor refrigerant temperature deviation delta T that only adder is calculated _nCompensate, in the present embodiment except that deviation compensator other parts and embodiment one identical.

Specifically, the indoor refrigerant temperature deviation delta T that calculates according to adder of deviation compensator _nWith the operating frequency Hz of compressor,, calculate indoor refrigerant temperature deviation delta T the linear function of penalty coefficient as the compressor operation frequency _nPenalty coefficient, again penalty coefficient and deviation delta T _nMultiply each other the deviation delta T after being compensated _n'.

During refrigeration: compensating unit calculates deviation delta T after the compensation according to following formula _e',

Δ T _e'=Δ T _e* (the formula 12 of a * Hz+b)

When heating: compensating unit calculates deviation delta T after the compensation according to following formula _c',

Δ T _c'=Δ T _c* (formula of a * Hz+b) is coefficient a in two formulas more than 13, and b is a constant.

Figure 10 and Fig. 4 are contrasted as can be seen, remove in the step 105 and only calculate Δ T _e' and do not calculate Δ T _b' outside, all the other steps 101,102,103,104,106,107,108 respectively with Fig. 4 in 401,402,403,404,406,407,408 identical.

Figure 11 and Fig. 5 are contrasted as can be seen, remove in the step 113 and only calculate Δ T _c' and do not calculate Δ T _b' outside, all the other steps 111,112,114,115,116 respectively with Fig. 4 in 401,402,404,405,406 identical.

Claims (8)

1, a kind of control method that is used for dragging many air-conditionings is characterized in that, may further comprise the steps:

(1), according to the indoor temperature T of reality _r, user's design temperature T _sAnd actual indoor-unit cooling-medium temperature T _n, calculate actual indoor-unit cooling-medium temperature T _nWith target refrigerant temperature T _N-setBetween refrigerant temperature difference Δ T _n

(2), according to the indoor-unit cooling-medium temperature T of reality _n, off-premises station refrigerant temperature T _g, outdoor temperature T _a, the total operating frequency Hz of compressor and actual compressor exhaust temperature T _b, calculate actual compressor exhaust temperature T _bWith target exhaust temperature T _kBetween delivery temperature difference Δ T _b

(3), by a multivariable controller according to described refrigerant temperature difference Δ T _nWith delivery temperature difference Δ T _bCalculate the variation delta Ev of expansion valve opening Ev and the variation delta Hz of operating frequency Hz,, control expansion valve and compressor respectively according to described Δ Ev and Δ Hz; Wherein, described expansion valve opening variation delta Ev is directly outputed to electric expansion valve to control its aperture; The variation delta Hz of described compressor operation frequency is input to a double-compressor running ability Distribution Calculation device, calculates two compressors running ability code N1, N2 separately to control two compressors by described capability distribution calculator.

2, according to claim 1 one control method of dragging many air-conditionings is characterized in that, in described (1) step, calculates actual indoor temperature T earlier _rWith user's design temperature T _sBetween temperature difference Δ T _rThen according to described temperature difference Δ T _r, calculate target refrigerant temperature T by target refrigerant temperature calculator _N-setCalculate actual indoor-unit cooling-medium temperature T at last _nWith described target refrigerant temperature T _N-setBetween refrigerant temperature difference Δ T _n

3, according to claim 1 one control method of dragging many air-conditionings is characterized in that, in described (2) step, earlier by the indoor-unit cooling-medium temperature T of a target exhaust temperature calculator according to described reality _n, off-premises station refrigerant temperature T _g, outdoor temperature T _aAnd the total operating frequency Hz of compressor, calculate compressor target exhaust temperature T _kAnd then calculate actual compressor exhaust temperature T _bWith described target exhaust temperature T _kBetween temperature difference exhaust Δ T _b

4, according to claim 1 one control method of dragging many air-conditionings is characterized in that, in described (3) step, earlier by a deviation compensator to described refrigerant temperature difference Δ T _nCompensate, with delivery temperature difference Δ T _bWith the refrigerant temperature difference Δ T after the compensation _n' be input to described multivariable controller simultaneously; Then by the dynamic model in the described multivariable controller according to described refrigerant temperature difference Δ T _n' and delivery temperature difference Δ T _bCalculate expansion valve opening variation delta Ev and operating frequency variation delta Hz, be respectively applied for control expansion valve and compressor.

5, according to claim 1 one control method of dragging many air-conditionings is characterized in that, in described (3) step, earlier by a deviation compensator simultaneously to described refrigerant temperature difference Δ T _nWith delivery temperature difference Δ T _bCompensate, with the Δ T after the compensation _n' and Δ T _b' be input to described multivariable controller simultaneously; Then by the Δ T of the dynamic model in the described multivariable controller after according to described compensation _n' and Δ T _b' calculate expansion valve opening variation delta Ev and operating frequency variation delta Hz, be respectively applied for control expansion valve and compressor.

6, according to claim 1 one control method of dragging many air-conditionings is characterized in that, in described (3) step, earlier by the dynamic model in the described multivariable controller according to described refrigerant temperature difference Δ T _nWith delivery temperature difference Δ T _bCalculate expansion valve opening variation delta Ev and operating frequency variation delta Hz; Again described Δ Ev and Δ Hz are input to a deviation compensator and compensate, draw aperture variation delta Ev ' and operating frequency variation delta Hz ' after the compensation, be respectively applied for control expansion valve and compressor.

7, according to claim 6 one control method of dragging many air-conditionings is characterized in that, in described (3) step, described expansion valve opening variation delta Ev ' is directly outputed to electric expansion valve to control its aperture; The variation delta Hz ' of described compressor operation frequency is input to a double-compressor running ability Distribution Calculation device, calculates two compressors running ability code N1, N2 separately to control two compressors by described capability distribution calculator.

8, according to each described one control method of dragging many air-conditionings in the claim 1 to 6, it is characterized in that described indoor-unit cooling-medium temperature difference Δ T _nComprise evaporator refrigerant temperature difference Δ T _eOr refrigerant condensation temperature difference Δ T _cIndoor-unit cooling-medium temperature difference Δ T after the described compensation _n' comprise the evaporator refrigerant temperature difference Δ T after the compensation _e' or the compensation after refrigerant condensation temperature difference Δ T _c'.

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