Background technology
The lithium bromide absorption type first-class heat pump unit mainly is comprised of regenerator, condenser, evaporator, absorber, heat exchanger, cryogenic fluid pump, solution pump etc.The principle of work of this unit can be divided into 3 cyclic processes: (1), lithium-bromide solution cyclic process, enter regenerator from absorber lean solution out through over-heat-exchanger, the driven thermal source heating of solution simmer down to strong solution in regenerator, strong solution enters absorber by regenerator through over-heat-exchanger and absorbs the refrigerant vapour of flash-pot to become lean solution.(2), the refrigerant cycle process, the refrigerant vapour that is evaporated from regenerator enters condenser to carry out condensing heat-exchange and becomes water as refrigerant and enter evaporator, absorbing the heat source water heat of vaporization in evaporator is refrigerant vapour, then is absorbed the solution absorption of device.(3), water system circulation, low-temperature heat source water circulates in evaporator tube, its heat is managed outer water as refrigerant and is absorbed; Warm water circulates in absorber, condenser tube, realizes temperature-rise period twice, absorbs for the first time the absorption heat of absorber, the heat of condensation of absorptive condenser for the second time.
Existing lithium bromide absorption type first-class heat pump unit, liquid level signal according to regenerator and evaporator, the start-stop of control solution pump and cryogenic fluid pump is adjusted solution and refrigerant cycle amount, when liquid level is higher than the liquid level state of a control, solution pump and cryogenic fluid pump stop, but this kind level regulating method is when sub-load, and regenerator and evaporator level fluctuation amplitude are larger, to cause the frequent start-stop of solution pump and cryogenic fluid pump, and then cause the unstable and load control accuracy decline of unit operation.
Existing lithium bromide absorption type first-class heat pump unit is not considered the control technology of unit inverse put heat.The inverse put heat of so-called source pump refers to that heat source water does not only provide heat to unit, on the contrary from the phenomenon of unit absorbing heat.When the generation inverse put was hot, if do not controlled, unit continued operation, can cause a large amount of wastes of the energy.
Existing lithium bromide absorption type first-class heat pump unit, normally dilute shutdown after, solution concentration and is retained a large amount of water as refrigerants greatly about about 55% in the evaporator.Shut down for a long time under the winter low temperature environment, may cause that solution crystallization, cryogen freeze.
Summary of the invention
The purpose of this invention is to provide a kind of lithium bromide absorption type first-class heat pump unit device and control method thereof, solve that unit onstream regeneration device and evaporator level fluctuation amplitude are large, unit inverse put heat, solution crystallization and cryogen frozen problem, realize steady control and the inverse put heat control of unit onstream regeneration device and evaporator liquid level, prevent that solution crystallization and cryogen from freezing.
The technical scheme that the present invention adopts for achieving the above object is: a kind of liquid level integrated control method of lithium bromide absorption type first-class heat pump unit is characterized in that: at first gather the liquid level state of a control by level electrode; Calculate the fluid level condition currency; Going out calculating according to range computation under the fluid level condition currency controls the running of output valve and control pump, stops; According to calculating the control output valve, adjust liquid circulation amount by frequency converter, circulation by-pass pipe and bypass regulator valve, adjust liquid level.
The liquid level integrated control method of described a kind of lithium bromide absorption type first-class heat pump unit is characterized in that: the fluid level condition currency is to draw according to fluid level condition time value the last week, predicted time, liquid level state of a control and forecast value revision coefficient calculations.
The liquid level integrated control method of described a kind of lithium bromide absorption type first-class heat pump unit is characterized in that: calculating the control output valve is that the initial value according to calculating control output valve, minimum and the fluid level condition currency of calculating control output valve calculate.
A kind of inverse put heat control method of lithium bromide absorption type first-class heat pump unit is characterized in that: at first detect heat source water out temperature, warm water temperature in and regenerator temperature by heat source water out temperature sensor, warm water inlet temperature sensor, regenerator temperature sensor; Judge inverse put heat; After the inverse put heat condition is set up, carry out variable valve control or the controlling alarm of source pump.
The inverse put heat control method of described a kind of lithium bromide absorption type first-class heat pump unit is characterized in that: the mode of judging inverse put heat has two kinds, and a kind of is when the heat source water outlet temperature is higher than the heat source water temperature in, is judged as inverse put heat; A kind of is to draw the hot state of inverse put according to heat source water temperature in, warm water temperature in and regenerator temperature calculating and judgement.
A kind of lithium bromide absorption type first-class heat pump unit device that described liquid level integrated control method and inverse put heat control method are used, comprise the pipeline of regenerator, condenser, evaporator, absorber, heat exchanger, solution pump, cryogenic fluid pump, level electrode and each link, it is characterized in that: solution pump frequency converter, cryogenic fluid pump frequency converter are installed; Be provided with the solution circulation by-pass pipe between solution pump and the absorber, the solution circulation by-pass pipe is provided with the solution bypass regulator valve; Be provided with the refrigerant cycle by-pass pipe between cryogenic fluid pump and the evaporator, the refrigerant cycle by-pass pipe is provided with the cryogen bypass regulator valve.
Described a kind of lithium bromide absorption type first-class heat pump unit device is characterized in that: be provided with warm water outlet temperature sensor, heat source water outlet temperature sensor, heat source water inlet temperature sensor, warm water outlet temperature sensor and regenerator temperature sensor.
Described a kind of lithium bromide absorption type first-class heat pump unit device is characterized in that: be provided for the cryogen delivery pipe of rapid dilution solution between evaporator and absorber, the cryogen delivery pipe is provided with the cryogen discharge solenoid valve.
Liquid level integrated control method of the present invention has been realized the steady control of unit onstream regeneration device and evaporator liquid level, and the stable control of unit load output; Inverse put heat control and warning make unit fortune realize energy-saving operation; Solution is diluted, prevent that solution crystallization and cryogen from freezing, unit is adapted under the low temperature environment shut down for a long time.
Embodiment
A kind of lithium bromide absorption type first-class heat pump unit device as shown in Figure 4, comprise regenerator 4, condenser 3, evaporator 1, absorber 2, heat exchanger 5, solution pump 11, cryogenic fluid pump 10, regenerator level electrode 14, the pipeline of evaporator level electrode 9, operation valve 16 and each link is installed respectively solution pump frequency converter 26, cryogenic fluid pump frequency converter 25 at solution pump 11 and cryogenic fluid pump 10 places; Be provided with solution circulation by-pass pipe 22 and solution circulation by-pass pipe 24 between solution pump 11 and the absorber 2, solution circulation by-pass pipe 22 and solution circulation by-pass pipe 24 are provided with solution bypass regulator valve 23; Be provided with refrigerant cycle by-pass pipe 19 and refrigerant cycle by-pass pipe 21 between cryogenic fluid pump 10 and the evaporator 1, refrigerant cycle by-pass pipe 19 and refrigerant cycle by-pass pipe 21 are provided with cryogen bypass regulator valve 20.Warm water outlet temperature sensor 12, heat source water outlet temperature sensor 7, heat source water inlet temperature sensor 8, warm water outlet temperature sensor 6 and regenerator temperature sensor 15 are installed.Be provided for cryogen delivery pipe 17 and the cryogen delivery pipe 18 of rapid dilution solution between evaporator 1 and absorber 2, cryogen delivery pipe 17 and cryogen delivery pipe 18 are provided with cryogen discharge solenoid valve 13.
Gather regenerator 4 and evaporator 1 fluid level condition by regenerator level electrode 14, evaporator level electrode 9, as shown in Figure 3: 1 is the design liquid level, and 2 is control electrode, and 3 is the state electrode, and 4 is ground-electrode.Wherein control electrode 2 is installed in design liquid level 1 place, according to solution level, the duration of contact of cryogen liquid level and control electrode and number of times, adopt the liquid level comprehensive controling algorithm to calculate the calculating control output valve of solution circulation amount, by solution pump frequency converter 26, solution circulation by-pass pipe 22, solution circulation by-pass pipe 24 and solution bypass regulator valve 23 are adjusted the solution circulation amount, by cryogenic fluid pump frequency converter 25, refrigerant cycle by-pass pipe 19, refrigerant cycle by-pass pipe 21 and cryogen bypass regulator valve 20 are adjusted the refrigerant cycle amount, thus continuous setup solution level and cryogen liquid level, reduce solution pump and cryogenic fluid pump start-stop.Liquid level integrated control method flow process is as shown in Figure 1: among the figure, Mv is for calculating the control output valve, Hz is the initial value (determining according to test situation) of Mv, a6 is Mv minimum (determining according to test situation), m1 is fluid level condition currency (Boolean quantity), E1 is liquid level state of a control (Boolean quantity), m1old is fluid level condition time value the last week (Boolean quantity), N is predicted time (determining according to test situation), and K is forecast value revision coefficient (determining according to test situation).
This flow process starts from step 101.
In step 102, judge whether for the first time calculating of beginning.
If the judgment is No, then execution in step 103 in step 102, determine that fluid level condition time value the last week m1old equals m1.
If the judgment is Yes, then execution in step 104 in step 102, determine that fluid level condition time value the last week m1old equals 0.
In step 105, (m1 old * (N-1)+E1 * K)/N relational expression is calculated fluid level condition currency m1 according to m1=.
In step 106, judge that whether fluid level condition currency m1 is less than 0.1.
If the judgment is Yes, then execution in step 109 in step 106, and fluid level condition currency m1 equals 0.1, and then execution in step 110.
If the judgment is No, then execution in step 107 in step 106, judge that whether fluid level condition currency m1 is greater than 1.
In step 107, judge that whether fluid level condition currency m1 is greater than 1.
If the judgment is Yes, then execution in step 108 in step 107, and fluid level condition currency m1 equals 1, and then execution in step 110.
If the judgment is No, then execution in step 110 in step 107.
In step 110, judge that whether fluid level condition currency m1 is less than or equal to 0.6.
If the judgment is Yes, then execution in step 111 in step 110, control output valve according to the calculating that Mv=Hz-(Hz-a6 * 12) * (m1-0.4)/0.2 relational expression calculates in this scope, and then execution in step 115.
If judge noly in step 110, then execution in step 112.
In step 112, judge that whether fluid level condition currency m1 is less than or equal to 0.8.
In step 112, if the judgment is Yes, then calculate according to Mv=a6 * 12 relational expressions and calculate the control output quantity, then execution in step 115.
In step 112, if the judgment is No, then execution in step 114.
In step 114, solution pump or cryogenic fluid pump stop.
In step 115, solution pump or cryogenic fluid pump running.
Flow process ends at step 116.
For preventing of inverse put heat, detecting heat source water out temperature, warm water temperature in and regenerator temperature by heat source water outlet temperature sensor 7, heat source water inlet temperature sensor 8, warm water inlet temperature sensor 12, regenerator temperature sensor 15 judges and control, inverse put heat control method flow process as shown in Figure 2, among the figure: Δ T=Ty-Th is temperature difference, Δ ty is the heat source water temperature in, Th is the warm water temperature in, and Tg is regenerator temperature.
The mode of judging inverse put heat has two kinds, and a kind of is when the heat source water outlet temperature is higher than the heat source water temperature in, is judged as inverse put heat; A kind of is to draw the hot state of inverse put according to heat source water temperature in, warm water temperature in and regenerator temperature calculating and judgement.
This flow process starts from step 201.
When the heat source water outlet temperature that detects is higher than the heat source water temperature in, be judged as inverse put heat, directly execution in step 204.
In step 202, whether judge regenerator temperature Tg greater than 90 ℃, if the judgment is Yes, then execution in step 203, if the judgment is No, then return and re-start judgement.
In step 203, whether judge temperature difference Δ T greater than 30 ℃, if the judgment is Yes, then the inverse put heat condition is set up.Then execution in step 204.If the judgment is No, then return and restart.
In step 204, the beginning timing, then execution in step 205.
In step 205, whether judge timing time by 5 minutes, if the judgment is Yes, namely the inverse put heat condition is not also removed after 5 minutes in stepless control, and then execution in step 207, and if the judgment is No, then execution in step 206.
In step 206, close the unit variable valve, then execution in step 208.
In step 207, carry out inverse put thermal warning, dilution shutdown protection.
In step 208, whether judge temperature difference Δ T less than 15 ℃, then return if the judgment is Yes and restart to judge whether inverse put heat, if the judgment is No, then restart timing.
For long-time halting problem under the low temperature environment, such as Fig. 4, cryogen delivery pipe 17, cryogen delivery pipe 18 and cryogen discharge solenoid valve 13 are set between evaporator 1 and absorber 2, when unit dilution running, open cryogen discharge solenoid valve 13, the water as refrigerant in the evaporator 1 is discharged into absorber 2, fully mix with solution, thereby accelerate the dilution running speed, shorten and dilute the duration of runs; Simultaneously, concentration was greatly about about 48% after water as refrigerant mixed with solution, and Tc and freezing temperature decrease prevent effectively that under low temperature environment water as refrigerant from freezing and solution crystallization.