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CN104121703A - Method and device for controlling direct heat type double-source heat pump water heater - Google Patents

Method and device for controlling direct heat type double-source heat pump water heater Download PDF

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Publication number
CN104121703A
CN104121703A CN201410377586.3A CN201410377586A CN104121703A CN 104121703 A CN104121703 A CN 104121703A CN 201410377586 A CN201410377586 A CN 201410377586A CN 104121703 A CN104121703 A CN 104121703A
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water
heat pump
water temperature
temperature
directly
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CN104121703B (en
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王玉军
秦黄辉
王颖
刘军
杨奕
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Jiangsu Tianshu Electric Appliance Co Ltd
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Jiangsu Tianshu Electric Appliance Co Ltd
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/40Solar thermal energy, e.g. solar towers

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Abstract

The invention discloses a method and device for controlling a direct heat type double-source heat pump water heater and relates to a fluid heater provided with a solar heat collector and a heat pump and a control method of the fluid heater. A control device detects the outlet water temperature of the solar water heater and changes the temperature control strategy according to the outlet water temperature. When the water temperature is in a first water temperature control zone, the heating amount of the heat pump is changed and the water temperature is controlled by adjusting the operation frequency of the direct heat type frequency conversion heat pump. When the water temperature is in a second water temperature control zone, the water temperature is controlled by changing the water supplementing speed of a water supplementing flow adjusting element, solar energy is fully used for accumulating heat, the heat pump heating time in sunlight intensity lowering periods before and after the sunset is shortened, adaptation to different sunlight intensities is achieved, the solar energy is preferably and fully utilized, the water inlet temperature of a unit is low, operation efficiency is high, safety and reliability are achieved, high-pressure protection of the unit due to the excessively high outlet water temperature can be avoided, the requirement for hot water supply can be met, meanwhile, the requirement for the power of a compressor can be lowered, the utilization rate of equipment is improved, and early-stage investment cost is lowered.

Description

A kind of directly-heated type double-source heat pump hot water machine control method and control device thereof
Technical field
The present invention relates to solar thermal collector and utilize fluid heater and the control method thereof of heat pump, relating in particular to a kind of control method and control device of directly-heated type double-source heat pump hot water machine.
Background technology
The high speed of the non-renewable and global reserves of current coal, oil, natural gas etc. " the fossil class energy " reduces; brought global energy shortage; add going from bad to worse of ball ecological environment; make to preserve the ecological environment, accelerate development and utilize regenerative resource, become the urgent and difficult task of the mankind.Air-source heat pump hot water more and more obtains consuming all approving because of advantages such as energy-saving and environmental protection.Air source heat pump hot water product mainly contains directly-heated type, circulating heating type, static heated type, and direct-heating heat pump water heater is able to large-scale popularization because simple, the little engineering cost of engineering water pipeline caliber is low, cold water does not enter heat storage water tank and hot water is stable etc. plurality of advantages is installed.On the other hand, solar product has also obtained consumers in general's approval because of energy-conservation, but when rainy weather does not have the sun or solar illuminance strong, solar product just need to be used electrical heating heat hot water, and this causes product operating cost also higher.Therefore, to carry out the mode in conjunction with heat hot water be the most energy-conservation for solar energy and air source heat pump.But, how by solar energy and heat pump water-heating machine organically the technical problem of combination never effectively solved.The scheme of at present main combination has:
The first combination is that circulation heating heat pump hot water machine and solar energy heat heat storage water tank simultaneously, for example, Chinese invention patent " the auxiliary heating ground source air-conditioning hot water integrated machine of solar energy " (Chinese invention patent number: ZL201110198359.0, Granted publication number: CN102269484B) disclose a kind of auxiliary heating ground source air-conditioning hot water integrated machine of solar energy that is applicable to the heating of life air-conditioning and hot water supply, comprise geothermal heat pump and solar heat exchanger, solar heat water-circulating pump, heat-pump hot-water circulating pump, hot water heat exchanger and heat storage water tank; Hot water heat exchanger is connected in the working medium circulation passage between compressor and reversal valve; Hot water heat exchanger is connected to described heat storage water tank by heat-pump hot-water circulating pump, forms heat-pump hot-water circulation canal, and solar heat exchanger is connected to described heat storage water tank by solar heat water-circulating pump, forms solar heat water circulation channel; Hot water in use heat storage water tank, as heating agent, is realized the direct-coupling of solar energy and geothermal heat pump.The advantage of this scheme is that heat pump and two heating systems of solar energy do not interfere with each other, independent operating.Its shortcoming is that solar energy and heat pump heat simultaneously when there being the solar time, and the hot water temperature of generation is very high, and hot water is easily scalded people, and hot water temperature is high simultaneously, and heat loss also can be very large.On the other hand, when water consumption is large, a large amount of cold water directly covers water tank, also can reduce the supply water temperature of hot water, causes water temperature unstable.
The second combination is that direct-heating heat pump water heater and solar energy combine heat hot water, the hot water of solar energy production is intake as direct-heating heat pump water heater, for example, Chinese invention patent " a kind of solar heat-pump water heater " (Chinese invention patent number: ZL201010214437.7, Granted publication number: CN101865537B) disclose a kind of solar heat-pump water heater, this water heater is placed in solar water container by the condenser in heat pump, directly the water after solar energy heating is heated, the technical scheme of this patent of invention is anti-solar vacuum heat-collecting pipe bombing module, water tank anti-frost protection module, water tank anti-dry protection module, water tank waterproof overflow protection module, connecting pipe anti-frost protection module, heat pump moves module automatically, heat pump economical operation module and a plurality of functions of lightning protection module integrate.Under which no matter solar energy heating effect how; the heat of solar absorption all may effectively utilize, and can guarantee that again 24 hours hot water demands, its shortcoming are when the water temperature of solar energy heating is spent higher than 45 simultaneously; heat pump leaving water temperature is too high, and high voltage protective easily occurs unit.
On the other hand, existing directly-heated type Teat pump boiler adopts thermostatic control valve regulation water temperature conventionally, no matter be mechanical type or the thermostatic mixing valves of electronic type, its basic working modes is in the situation that not changing heat pump and heating power, by changing valve opening, changes discharge and controls water temperature.Yet, because thermostatic mixing valves circulation bore is little, carry out differential force, also easily by impurity, stopped up.Especially when the water temperature of solar energy heating raises, because the actuating range of thermostatic mixing valves regulating water flow is narrow, very easily occur that unit can not be controlled at the leaving water temperature of setting, the too high unit generation high voltage protective problem that causes of leaving water temperature.
In addition, although above-mentioned prior art scheme has solved the combination problem of heat pump and solar energy, because summer fever water demand is little, in addition summer environment temperature is high, the reason such as the illumination of solar energy is good, and heating capacity during source pump water heating is well beyond demand, the unit working time is very short, there is a greater part of time in holding state, cause utilization rate of equipment and installations low, the problem that the investment payback time is long.
Summary of the invention
The object of the invention is to provide a kind of control method of controlling for the operation of directly-heated type double-source heat pump hot water machine, for solving the technical problem of the combination of solar water heater and directly-heated type heat pump.
The present invention solves the problems of the technologies described above adopted technical scheme:
A kind of directly-heated type double-source heat pump hot water machine control method, operation for directly-heated type double-source heat pump hot water machine is controlled, described directly-heated type double-source heat pump hot water machine comprises directly-heated type frequency conversion heat pump, solar water heater, heat storage water tank, refill flow regulating element and control device, is characterized in that comprising the following steps:
S100: operating parameter setting module is obtained hot water consumption per day Qwd setting value, heating duration setting value Qht, the first water temperature setting value Ts1, the second water temperature setting value Ts2, leaving water temperature permissible variation Δ T, the water level higher limit Wsx of heat storage water tank, and heat pump minimum operation frequency Fzd;
S200: the water yield detects control module according to hot water consumption per day Qwd setting value and heating duration setting value Qht, determine predetermined moisturizing speed Vwh=Qwd/Qht, start directly-heated type frequency conversion heat pump, open entering water electromagnetic valve and refill flow regulating element, according to predetermined moisturizing speed Vwh moisturizing hot water preparing;
S220: constant flow variable-frequency heating temperature control strategy: water temperature detects control module and detects in real time the solar energy leaving water temperature Tc2 of solar water heater by the second cooling-water temperature sensor, according to solar energy leaving water temperature Tc2, regulate the running frequency Frb of directly-heated type frequency conversion heat pump, by changing heat pump heating capacity, leaving water temperature is remained in the scope of first water temperature control interval Ts1+ Δ T >=Tcs >=Ts1-Δ T;
S300: in the situation that intensity of sunshine is high, rising along with solar energy leaving water temperature Tc2, the running frequency Frb of directly-heated type frequency conversion heat pump constantly reduces, if running frequency Frb is reduced to heat pump minimum operation frequency Fzd, stop the operation of directly-heated type frequency conversion heat pump, rely on solar energy heating hot water preparing completely;
S320: constant temperature variable-flow temperature control strategy: water temperature detects control module and detects in real time the solar energy leaving water temperature Tc2 of solar water heater by the second cooling-water temperature sensor, when solar energy leaving water temperature Tc2 is elevated to the second water temperature setting value Ts2, the water yield detects control module by refill flow controller, the moisturizing speed Vw that regulates refill flow regulating element, is controlled within the scope of second water temperature control interval Ts1+ Δ T < Tc2≤Ts2 leaving water temperature;
S340: detect high water tank Wyw by liquid level sensor, if high water tank Wyw arrives water level higher limit Wsx, go to step S400;
S380: along with the reduction of solar illumination, moisturizing speed Vw regulates gradually and is returned to predetermined moisturizing speed Vwh, if solar energy leaving water temperature Tc2 drops to Tc2≤Ts1-Δ T, returns to step S200, otherwise, step S320 returned to;
S400: stop the operation of directly-heated type frequency conversion heat pump, close entering water electromagnetic valve and refill flow regulating element, stop hot water preparing.
A kind of preferably technical scheme of directly-heated type double-source heat pump hot water machine control method of the present invention, characterized by further comprising following timing controlled operating procedure:
Between described step S100 and S200, also comprise step S120:
S120: operating parameter setting module is obtained initial heat time Ts and stopped heat time Te, order heating duration setting value Qht=Te-Ts, starts calendar scheduling and waits to arrive initial heat time Ts;
Between described step S340 and S380, also comprise step S360:
S360: stop heat time Te if operation timing arrives, go to step S400.
A kind of better technical scheme of directly-heated type double-source heat pump hot water machine control method of the present invention, characterized by further comprising following steps:
In step S220 and step S320, water temperature detects control module and also by the first temperature sensor, detects in real time heat pump leaving water temperature Tc1, calculates the temperature difference Tc=Tc2-Tc1 between solar water heater water-in and water-out;
In step S220, frequency conversion heat pump controller is determined the coefficient of pid algorithm according to solar energy leaving water temperature Tc2 and temperature difference of outlet water Δ Tc, utilizes pid algorithm to control the running frequency Frb of directly-heated type frequency conversion heat pump;
In step S320, refill flow controller is determined the coefficient of pid algorithm according to solar energy leaving water temperature Tc2 and temperature difference of outlet water Δ Tc, utilizes pid algorithm to control the moisturizing speed Vw of refill flow regulating element.
A kind of improved technical scheme of directly-heated type double-source heat pump hot water machine control method of the present invention, is characterized in that after step S400, also comprises the step S420 that carries out constant temperature circulating low frequency preservation and controlling strategy:
S420: constant temperature circulating low frequency preservation and controlling strategy: water temperature detects control module and detects the water tank water temperature Tsx of heat storage water tank by the 3rd cooling-water temperature sensor, along with the water temperature in heat storage water tank, because dispel the heat, reduce, when water tank water temperature Tsx=Ts1-Δ T, start Constant Temperature Circulator and directly-heated type frequency conversion heat pump, heat pump moves according to minimum operation frequency Fzd, water in heat storage water tank is incubated to circulating-heating, water tank water temperature Tsx is remained in the scope of Ts1+ Δ T > Tsx >=Ts1-Δ T.
Another object of the present invention is to provide a kind of specialized designs for realizing the control device of above-mentioned directly-heated type double-source heat pump hot water machine control method.The present invention solves the problems of the technologies described above adopted technical scheme:
A kind of for realizing the directly-heated type double-source heat pump hot water machine control device of above-mentioned directly-heated type double-source heat pump hot water machine control method, comprise operating parameter setting module, frequency conversion heat pump controller, water temperature detects control module, and the water yield detects control module and refill flow controller; It is characterized in that: described water temperature detects the input of control module, is connected to operating parameter setting module, the first temperature sensor and the second temperature sensor; Described water temperature detects the output of control module, is connected to the input of frequency conversion heat pump controller and refill flow controller; The output of described frequency conversion heat pump controller, is connected to directly-heated type frequency conversion heat pump; The described water yield detects the input of control module, is connected to operating parameter setting module, liquid level sensor and the second temperature sensor; The described water yield detects the output of control module, by refill flow controller, is connected to refill flow regulating element.
A kind of preferably technical scheme of directly-heated type double-source heat pump hot water machine control device of the present invention, is characterized in that described control device also comprises constant temperature circulating pump controller; Described three-temperature sensor is connected to the input that water temperature detects control module; Described water temperature detects the output of control module, by constant temperature circulating pump controller, is connected to Constant Temperature Circulator.
A kind of better technical scheme of directly-heated type double-source heat pump hot water machine control device of the present invention, it is characterized in that described control device adopts the chip microprocessor with multi-channel A/D translation interface and multi-channel PWM output interface to realize programme-control, described liquid level sensor, the first temperature sensor, the second temperature sensor and three-temperature sensor are connected to chip microprocessor by the A/D translation interface of microprocessor; Described control device utilizes the PWM output interface of microprocessor, for frequency conversion heat pump controller and refill flow controller provide VFC output signal or valve opening, controls output signal.
The invention has the beneficial effects as follows:
1, directly-heated type double-source heat pump hot water machine control method of the present invention and control device thereof, take constant flow variable-frequency heating temperature control strategy, by identification solar water heater leaving water temperature, and the running frequency that changes directly-heated type frequency conversion heat pump according to leaving water temperature is controlled water temperature, the method that replaces the use temperature control water valve regulating water flow of existing directly-heated type heat pump routine, can adapt to different intensity of sunshines, make the water temperature stability that enters heat storage water tank at design temperature; After solar water heater series connection is arranged on directly-heated type frequency conversion heat pump delivery port; machine set compressor operates in low frequency energy-saving state when having illuminance; the heating load of source pump reduces automatically until out of service; unit inflow temperature is low; operational efficiency is high and safe and reliable, can avoid causing because leaving water temperature is too high unit high voltage protective.
2, directly-heated type double-source heat pump hot water machine control method of the present invention and control device thereof, by adopting constant temperature variable-flow temperature control strategy, can make full use of solar energy savings heat, save the heat pump time that sunset front and back intensity of sunshine reduces the period, reach the object of effectively utilizing solar energy to save electric energy, and heat duration by prolongation, can be when meeting hot water supply in 24 hours, the power requirement of reduction to heat pump compressor, the utilization rate of raising equipment, reduces unit up-front investment cost.
3, directly-heated type double-source heat pump hot water machine control method of the present invention and control device thereof, having overcome solar water heating system wants preferential and makes full use of solar energy, must identify the different intensity of sunshines of period and the technology prejudice of solar energy heating amount, the mode of temperature controlling mode is selected in employing automatically according to solar water heater leaving water temperature, solar energy heating and heat pump water-heating machine heating are organically combined, do not need to identify this uncertain factor of intensity of sunshine, just can realize preferentially and make full use of the heat that solar energy produces.
Accompanying drawing explanation
Fig. 1 is the structural representation of directly-heated type double-source heat pump hot water machine of the present invention;
Fig. 2 is the schematic diagram of the control device of directly-heated type double-source heat pump hot water machine of the present invention;
Fig. 3 is directly-heated type double-source heat pump hot water machine control method flow chart of the present invention.
The label of each parts in above figure: 100-directly-heated type frequency conversion heat pump, 110-entering water electromagnetic valve, 120-condenser, 200-solar water heater, 210-thermal-collecting tube, 220-inlet water tank, 230-water tank, 300-heat storage water tank, 310-drain valve, 320-overflow pipe, 400-refill flow regulating element, 410-Constant Temperature Circulator, 500-control device, 510-operating parameter setting module, 520-frequency conversion heat pump controller, 530-water temperature detects control module, 531-the first cooling-water temperature sensor, 532-the second cooling-water temperature sensor, 533-the second cooling-water temperature sensor, 534-constant temperature circulating pump controller, the 540-water yield detects control module, 541-liquid level sensor, 550-refill flow controller.
The specific embodiment
In order to understand better technique scheme of the present invention, below in conjunction with drawings and Examples, describe in detail further.Fig. 1 is an embodiment of directly-heated type double-source heat pump hot water machine of the present invention, comprise directly-heated type frequency conversion heat pump 100, solar water heater 200, heat storage water tank 300, refill flow regulating element 400 and control device 500, described directly-heated type frequency conversion heat pump 100 comprises the heat-exchanging water pipeline that entering water electromagnetic valve 110 and condenser 120 are composed in series, the cold water inlet of directly-heated type frequency conversion heat pump 100, successively by entering water electromagnetic valve 110 and condenser 120, is communicated to the hot water outlet of directly-heated type frequency conversion heat pump 100; In Fig. 1, omitted the known refrigerant loop that comprises compressor.The thermal-collecting tube 210 of described solar water heater 200 is low side water inlet, high-end water flowing out structure, the inlet pipeline of solar water heater 200 is connected to the bottom of thermal-collecting tube 210 by inlet water tank 220, the high-end of thermal-collecting tube 210 is connected to hot water effluent's pipeline by water tank 230, outside cold water supply pipeline is by refill flow regulating element 400, be connected to the cold water inlet of directly-heated type frequency conversion heat pump 100, the hot water outlet of directly-heated type frequency conversion heat pump 100 is received the inlet pipeline of solar water heater 200, and the outlet pipeline of solar water heater 200 is connected to heat storage water tank 300, the hot water effluent of directly-heated type frequency conversion heat pump 100, flows through the thermal-collecting tube 210 of solar water heater 200, absorbs after the solar heat secondary temperature elevation that thermal-collecting tube 210 gathers, and flows in heat storage water tank 300, and the hot water by heat storage water tank 300 is for water out heat outputting water, hot water effluent's pipeline of directly-heated type frequency conversion heat pump 100 is provided with the first temperature sensor 531, and hot water effluent's pipeline of solar water heater 200 is provided with the second temperature sensor 532, described control device 500 is by the second cooling-water temperature sensor 532, detect the leaving water temperature of solar water heater 200, according to the leaving water temperature of solar water heater 200, change temperature control strategy: when leaving water temperature is in the first water temperature control interval, heat pump is with constant moisturizing speed supply cold water, by changing the running frequency of directly-heated type frequency conversion heat pump 100, control water temperature, when leaving water temperature is in the second water temperature control interval, directly-heated type frequency conversion heat pump 100 is out of service, by changing the moisturizing speed of refill flow regulating element 400, control water temperature, thereby in the situation that guaranteeing to supply water for 24 hours, make full use of solar energy hot water preparing.The first described water temperature control interval is the water temperature range that is no more than normal hot water supply water temperature permissible variation, for example, and 45 ± 5 ℃; The second described water temperature control interval is to be no more than the water temperature range between the highest permission water temperature higher than normal hot water supply water temperature, for example, and 50~60 ℃.
In the embodiment shown in fig. 1, the bottom of described heat storage water tank 300 is provided with drain valve 310 and overflow pipe 320, emptying water tank when drain valve 310 cleans for overhauling, and overflow pipe 320 water tank when preventing that liquid level is out of control diffuses out.
In the embodiment of the directly-heated type double-source heat pump hot water machine of the present invention shown in Fig. 1, described refill flow regulating element 400 is frequency conversion small pumps, and described refill flow controller 550 is small pump frequency-variable controllers; Described control device 500, according to the leaving water temperature of solar water heater 200, regulates moisturizing speed by changing the operating frequency of frequency conversion small pump, and leaving water temperature is controlled in the second water temperature control interval.
According to another embodiment of directly-heated type double-source heat pump hot water machine of the present invention, described refill flow regulating element 400 is electric flow control valves, and described refill flow controller 550 is motorized adjustment valve controls; Described control device 500, according to the leaving water temperature of solar water heater 200, by changing the aperture of electric flow control valve, is controlled in the second water temperature control interval leaving water temperature.
In the embodiment of the directly-heated type double-source heat pump hot water machine of the present invention shown in Fig. 1, on the entering water electromagnetic valve 110 of directly-heated type frequency conversion heat pump 100 and the connecting line of condenser 120, be provided with constant temperature water inlet; Position at the bottom of the bottom of heat storage water tank 300 is near case is provided with circulating hot water delivery port; Described circulating hot water delivery port is connected to described constant temperature water inlet by Constant Temperature Circulator 410; In the inner close hot water water supply of heat storage water tank 300 exit, be provided with the 3rd cooling-water temperature sensor 533; Described control device 500 detects the water tank water temperature of heat storage water tank by the 3rd cooling-water temperature sensor 533; Water temperature in heat storage water tank is because dispel the heat while reducing, and described control device 500 starts Constant Temperature Circulator 410 and directly-heated type frequency conversion heat pumps 100, and the hot water of heat storage water tank 300 interior storages is incubated to circulating-heating.
An embodiment of the control device 500 of directly-heated type double-source heat pump hot water machine of the present invention as shown in Figure 2, comprise operating parameter setting module 510, frequency conversion heat pump controller 520, water temperature detects control module 530, and the water yield detects control module 540 and refill flow controller 550; Described water temperature detects the input of control module 530, is connected to operating parameter setting module 510, the first temperature sensor 531 and the second temperature sensor 532; Described water temperature detects the output of control module 530, is connected to the input of frequency conversion heat pump controller 520 and refill flow controller 550; The output of described frequency conversion heat pump controller 520, is connected to directly-heated type frequency conversion heat pump 100; The described water yield detects the input of control module 540, is connected to operating parameter setting module 510, liquid level sensor 541 and the second temperature sensor 532; The described water yield detects the output of control module 540, by refill flow controller 550, is connected to refill flow regulating element 400.
In the embodiment of the control device 500 of the directly-heated type double-source heat pump hot water machine of the present invention shown in Fig. 2, control device 500 also comprises constant temperature circulating pump controller 534; Described three-temperature sensor 533 is connected to the input that water temperature detects control module 530; Described water temperature detects the output of control module 530, by constant temperature circulating pump controller 534, is connected to Constant Temperature Circulator 410.
According to an embodiment of directly-heated type double-source heat pump hot water machine of the present invention, described control device 500 adopts the chip microprocessor with multi-channel A/D translation interface and multi-channel PWM output interface to realize programme-control, and described liquid level sensor 541, the first temperature sensor 531, the second temperature sensor 532 and three-temperature sensor 533 is connected to chip microprocessor by the A/D translation interface of microprocessor; Described control device 500 utilizes the PWM output interface of microprocessor, for frequency conversion heat pump controller 520 and refill flow controller 550 provide VFC output signal or valve opening, controls output signal.
Fig. 3 is the flow chart of an embodiment of directly-heated type double-source heat pump hot water machine control method of the present invention, comprises the following steps:
S100: operating parameter setting module is obtained hot water consumption per day Qwd setting value, heating duration setting value Qht, the first water temperature setting value Ts1, the second water temperature setting value Ts2, leaving water temperature permissible variation Δ T, the water level higher limit Wsx of heat storage water tank, and heat pump minimum operation frequency Fzd; According to a preferred embodiment of directly-heated type double-source heat pump hot water machine of the present invention, heating duration setting value Qht is set to 20 hours, like this, can be when meeting hot water supply in 24 hours, the power requirement of reduction to heat pump compressor, thereby improve the utilization rate of equipment, reduce up-front investment cost.
S200: the water yield detects control module according to hot water consumption per day Qwd setting value and heating duration setting value Qht, determine predetermined moisturizing speed Vwh=Qwd/Qht, start directly-heated type frequency conversion heat pump, open entering water electromagnetic valve and refill flow regulating element, according to predetermined moisturizing speed Vwh moisturizing hot water preparing;
S220: constant flow variable-frequency heating temperature control strategy: water temperature detects control module and detects in real time the solar energy leaving water temperature Tc2 of solar water heater by the second cooling-water temperature sensor, according to solar energy leaving water temperature Tc2, regulate the running frequency Frb of directly-heated type frequency conversion heat pump, by changing heat pump heating capacity, leaving water temperature is remained in the scope of first water temperature control interval Ts1+ Δ T >=Tcs >=Ts1-Δ T;
S300: in the situation that intensity of sunshine is high, rising along with solar energy leaving water temperature Tc2, the running frequency Frb of directly-heated type frequency conversion heat pump constantly reduces, if running frequency Frb is reduced to heat pump minimum operation frequency Fzd, stop the operation of directly-heated type frequency conversion heat pump, rely on solar energy heating hot water preparing completely;
S320: constant temperature variable-flow temperature control strategy: water temperature detects control module and detects in real time the solar energy leaving water temperature Tc2 of solar water heater by the second cooling-water temperature sensor, when solar energy leaving water temperature Tc2 is elevated to the second water temperature setting value Ts2, the water yield detects control module by refill flow controller, regulate the moisturizing speed Vw of refill flow regulating element, leaving water temperature is controlled within the scope of second water temperature control interval Ts1+ Δ T < Tc2≤Ts2, to make full use of the heat of solar energy; In the situation that intensity of sunshine is high, directly-heated type double-source heat pump hot water machine of the present invention is by constant temperature variable-flow temperature control strategy, automatically water temperature is elevated to the highest permission water temperature, and accelerate moisturizing speed, make heat storage water tank arrive in advance default water level higher limit Wsx, thereby can make full use of solar energy savings heat, save the heat pump time that sunset front and back intensity of sunshine reduces the period, reach the object of effectively utilizing solar energy to save electric energy.
S340: detect high water tank Wyw by liquid level sensor, if high water tank Wyw arrives water level higher limit Wsx, go to step S400;
S380: along with the reduction of solar illumination, moisturizing speed Vw regulates gradually and is returned to after predetermined moisturizing speed Vwh, keep determining moisturizing speed Vwh moisturizing, if solar energy leaving water temperature Tc2 continues to decline, while reaching Tc2≤Ts1-Δ T, return to step S200 and start directly-heated type frequency conversion heat pump, recover constant flow variable-frequency heating temperature control strategy; Otherwise, return to step S320 and continue to carry out constant temperature variable-flow temperature control strategy;
S400: stop the operation of directly-heated type frequency conversion heat pump, close entering water electromagnetic valve and refill flow regulating element, stop hot water preparing.
In the embodiment of the directly-heated type double-source heat pump hot water machine control method of the present invention shown in Fig. 3, also comprise following timing controlled operating procedure:
Between described step S100 and S200, also comprise step S120:
S120: operating parameter setting module is obtained initial heat time Ts and stopped heat time Te, order heating duration setting value Qht=Te-Ts, starts calendar scheduling and waits to arrive initial heat time Ts; One group of preferred initial heat time Ts is 22 points, and stopping heat time Te is 18 points, can make full use of valley power night like this, and can make full use of solar energy daytime, reaches energy-efficient effect.
Between described step S340 and S380, also comprise step S360:
S360: stop heat time Te if operation timing arrives, go to step S400.
According to a preferred embodiment of directly-heated type double-source heat pump hot water machine control method of the present invention, further comprising the steps of:
In step S220 and step S320, water temperature detects control module and also by the first temperature sensor, detects in real time heat pump leaving water temperature Tc1, calculates the temperature difference Tc=Tc2-Tc1 between solar water heater water-in and water-out;
In step S220, frequency conversion heat pump controller is determined the coefficient of pid algorithm according to solar energy leaving water temperature Tc2 and temperature difference of outlet water Δ Tc, utilizes pid algorithm to control the running frequency Frb of directly-heated type frequency conversion heat pump;
In step S320, refill flow controller is determined the coefficient of pid algorithm according to solar energy leaving water temperature Tc2 and temperature difference of outlet water Δ Tc, utilizes pid algorithm to control the moisturizing speed Vw of refill flow regulating element.
In the embodiment of the directly-heated type double-source heat pump hot water machine control method of the present invention shown in Fig. 3, be also included in after step S400 stops water heating, carry out the step S420 of constant temperature circulating low frequency preservation and controlling strategy:
S420: constant temperature circulating low frequency preservation and controlling strategy: water temperature detects control module and detects the water tank water temperature Tsx of heat storage water tank by the 3rd cooling-water temperature sensor, along with the water temperature in heat storage water tank, because dispel the heat, reduce, when water tank water temperature Tsx=Ts1-Δ T, start Constant Temperature Circulator and directly-heated type frequency conversion heat pump, heat pump moves according to minimum operation frequency Fzd, water in heat storage water tank is incubated to circulating-heating, water tank water temperature Tsx is remained in the scope of Ts1+ Δ T > Tsx >=Ts1-Δ T.
Those of ordinary skill in the art will be appreciated that; above embodiment is only for technical scheme of the present invention is described; and be not used as limitation of the invention; any variation of the above embodiment being done based on connotation of the present invention, modification, all will drop in the protection domain of claim of the present invention.

Claims (7)

1. a directly-heated type double-source heat pump hot water machine control method, operation for directly-heated type double-source heat pump hot water machine is controlled, described directly-heated type double-source heat pump hot water machine comprises directly-heated type frequency conversion heat pump, solar water heater, heat storage water tank, refill flow regulating element and control device, is characterized in that comprising the following steps:
S100: operating parameter setting module is obtained hot water consumption per day Qwd setting value, heating duration setting value Qht, the first water temperature setting value Ts1, the second water temperature setting value Ts2, leaving water temperature permissible variation Δ T, the water level higher limit Wsx of heat storage water tank, and heat pump minimum operation frequency Fzd;
S200: the water yield detects control module according to hot water consumption per day Qwd setting value and heating duration setting value Qht, determine predetermined moisturizing speed Vwh=Qwd/Qht, start directly-heated type frequency conversion heat pump, open entering water electromagnetic valve and refill flow regulating element, according to predetermined moisturizing speed Vwh moisturizing hot water preparing;
S220: constant flow variable-frequency heating temperature control strategy: water temperature detects control module and detects in real time the solar energy leaving water temperature Tc2 of solar water heater by the second cooling-water temperature sensor, according to solar energy leaving water temperature Tc2, regulate the running frequency Frb of directly-heated type frequency conversion heat pump, by changing heat pump heating capacity, leaving water temperature is remained in the scope of first water temperature control interval Ts1+ Δ T >=Tcs >=Ts1-Δ T;
S300: in the situation that intensity of sunshine is high, rising along with solar energy leaving water temperature Tc2, the running frequency Frb of directly-heated type frequency conversion heat pump constantly reduces, if running frequency Frb is reduced to heat pump minimum operation frequency Fzd, stop the operation of directly-heated type frequency conversion heat pump, rely on solar energy heating hot water preparing completely;
S320: constant temperature variable-flow temperature control strategy: water temperature detects control module and detects in real time the solar energy leaving water temperature Tc2 of solar water heater by the second cooling-water temperature sensor, when solar energy leaving water temperature Tc2 is elevated to the second water temperature setting value Ts2, the water yield detects control module by refill flow controller, the moisturizing speed Vw that regulates refill flow regulating element, is controlled within the scope of second water temperature control interval Ts1+ Δ T < Tc2≤Ts2 leaving water temperature;
S340: detect high water tank Wyw by liquid level sensor, if high water tank Wyw arrives water level higher limit Wsx, go to step S400;
S380: along with the reduction of solar illumination, moisturizing speed Vw regulates gradually and is returned to predetermined moisturizing speed Vwh, if solar energy leaving water temperature Tc2 drops to Tc2≤Ts1-Δ T, returns to step S200, otherwise, step S320 returned to;
S400: stop the operation of directly-heated type frequency conversion heat pump, close entering water electromagnetic valve and refill flow regulating element, stop hot water preparing.
2. directly-heated type double-source heat pump hot water machine control method according to claim 1, characterized by further comprising following timing controlled operating procedure:
Between described step S100 and S200, also comprise step S120:
S120: operating parameter setting module is obtained initial heat time Ts and stopped heat time Te, order heating duration setting value Qht=Te-Ts, starts calendar scheduling and waits to arrive initial heat time Ts;
Between described step S340 and S380, also comprise step S360:
S360: stop heat time Te if operation timing arrives, go to step S400.
3. directly-heated type double-source heat pump hot water machine control method according to claim 1, characterized by further comprising following steps:
In step S220 and step S320, water temperature detects control module and also by the first temperature sensor, detects in real time heat pump leaving water temperature Tc1, calculates the temperature difference Tc=Tc2-Tc1 between solar water heater water-in and water-out;
In step S220, frequency conversion heat pump controller is determined the coefficient of pid algorithm according to solar energy leaving water temperature Tc2 and temperature difference of outlet water Δ Tc, utilizes pid algorithm to control the running frequency Frb of directly-heated type frequency conversion heat pump;
In step S320, refill flow controller is determined the coefficient of pid algorithm according to solar energy leaving water temperature Tc2 and temperature difference of outlet water Δ Tc, utilizes pid algorithm to control the moisturizing speed Vw of refill flow regulating element.
4. according to the directly-heated type double-source heat pump hot water machine control method described in claim 1,2 or 3, it is characterized in that after step S400 water, also comprise the step S420 that carries out constant temperature circulating low frequency preservation and controlling strategy:
S420: constant temperature circulating low frequency preservation and controlling strategy: water temperature detects control module and detects the water tank water temperature Tsx of heat storage water tank by the 3rd cooling-water temperature sensor, along with the water temperature in heat storage water tank, because dispel the heat, reduce, when water tank water temperature Tsx=Ts1-Δ T, start Constant Temperature Circulator and directly-heated type frequency conversion heat pump, heat pump moves according to minimum operation frequency Fzd, water in heat storage water tank is incubated to circulating-heating, water tank water temperature Tsx is remained in the scope of Ts1+ Δ T > Tsx >=Ts1-Δ T.
5. one kind for realizing the directly-heated type double-source heat pump hot water machine control device of the directly-heated type double-source heat pump hot water machine control method described in arbitrary claim of claim 1 to 4, comprise operating parameter setting module, frequency conversion heat pump controller, water temperature detects control module, and the water yield detects control module and refill flow controller; It is characterized in that: described water temperature detects the input of control module, is connected to operating parameter setting module, the first temperature sensor and the second temperature sensor; Described water temperature detects the output of control module, is connected to the input of frequency conversion heat pump controller and refill flow controller; The output of described frequency conversion heat pump controller, is connected to directly-heated type frequency conversion heat pump; The described water yield detects the input of control module, is connected to operating parameter setting module, liquid level sensor and the second temperature sensor; The described water yield detects the output of control module, by refill flow controller, is connected to refill flow regulating element.
6. directly-heated type double-source heat pump hot water machine control device according to claim 5, be used for realizing directly-heated type double-source heat pump hot water machine control method claimed in claim 5, it is characterized in that described control device also comprises constant temperature circulating pump controller; Described three-temperature sensor is connected to the input that water temperature detects control module; Described water temperature detects the output of control module, by constant temperature circulating pump controller, is connected to Constant Temperature Circulator.
7. according to the directly-heated type double-source heat pump hot water machine control device described in claim 5 or 6, it is characterized in that described control device adopts the chip microprocessor with multi-channel A/D translation interface and multi-channel PWM output interface to realize programme-control, described liquid level sensor, the first temperature sensor, the second temperature sensor and three-temperature sensor are connected to chip microprocessor by the A/D translation interface of microprocessor; Described control device utilizes the PWM output interface of microprocessor, for frequency conversion heat pump controller and refill flow controller provide VFC output signal or valve opening, controls output signal.
CN201410377586.3A 2014-08-01 2014-08-01 Method and device for controlling direct heat type double-source heat pump water heater Expired - Fee Related CN104121703B (en)

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