Patent Application
20200116411
The present invention relates to an ice storage system and method for storing ice, especially to an ice storage amount adjusting system and a method for adjusting ice storage amount.
Large air-conditioner is generally equipped with chiller (ice maker) for making ice. The chiller makes ices during off-peak hour when the utility fee is cheaper, while the air-conditioner uses the pre-manufactured ices for heat exchange during peak hour when the utility fee is more expensive, thus saving the cost for running the air-conditioner.
Generally, the conventional chiller starts running at above-mentioned off-peak hour (such as at night time) and starts ice making procedure after starting. The chiller stops from making ices when the ice tank is full. More particularly, the conventional chiller performs ice making procedure at least one time per day and has fixed ice storage amount for each ice making procedure. However, the internal factors (such as personnel number and activity types) impacting on the air conditioning of the buildings and the external factors (such as temperature and humidity) impacting on the air conditioning of the buildings are varied every day. The resource is wasted if the chiller makes ices with fixed amount every day.
More particularly, in case that the ice storage amount of the chiller is excessive, the unused ices gradually melt as time elapses. This causes energy waste for making unnecessary ice. Besides, the chiller has ice-bridge effect during ice making procedure, namely, the ice grows from the portion near the pipe. The accumulated energy waste is huge if the amount of ice produced by the chiller is beyond the amount required by the air conditioner for everyday day usage.
It is an object of the present invention to provide an ice storage amount adjusting system and method for the same. The potential loading of the air-conditioner for the coming time can be predicted and the chiller is controlled to make corresponding amount of ice based on the prediction result, thus prevent energy waste.
Accordingly, the present invention provides an ice storage amount adjusting system applied for a building. The system comprises: a central monitoring computer; a chiller communicated with the central monitoring computer and supplying chilled water to an air-conditioner in the building; an air-condition scheduler outputting a scheduling parameter during a first time for the air-conditioner; an indoor temperature setting module outputting an indoor-temperature setting condition during the first time; a shell-feature collecting module outputting a shell loading factor during the first time; a weather forecasting data collecting module outputting a weather forecasting data during the second time, wherein the second time is later than the first time; and an air-condition loading predictor communicated with the central monitoring computer through an energy management platform.
The air-condition loading predictor predicts an air-condition loading of the air-conditioner during the second time based on the scheduling parameter, the indoor-temperature setting condition, the shell loading factor and the weather forecasting data, and the air-condition loading predictor generates a prediction result associated with the air-condition loading and sends the prediction result to the energy management platform. The energy management platform controls the central monitoring computer to output a target ice storage amount based on the prediction result to the chiller, and the chiller adjusts an ice storage amount required in the second time based on the target ice storage amount.
Accordingly, the present invention provides a method for adjusting ice storage amount. The method is applied to a chiller in a building, and comprises: a) using an air-condition scheduler to output a scheduling parameter for the air-conditioner during a first time; b) using an indoor temperature setting module to output an indoor-temperature setting condition during the first time; c) using a shell-feature collecting module to output a shell loading factor during the first time; d) using a weather forecasting data collecting module to output a weather forecasting data during the second time, wherein the second time is later than the first time; e) predicting an air-condition loading of the air-conditioner during the second time based on the scheduling parameter, the indoor-temperature setting condition, the shell loading factor and the weather forecasting data and generating a prediction result; f) providing the prediction result to an energy management platform; and g) the energy management platform controlling the central monitoring computer to output a target ice storage amount to the chiller based on the prediction result, the chiller adjusting an ice storage amount required in the second time based on the target ice storage amount.
The system and method according to the present invention can control the chiller to make corresponding amount of ice based on the predicted potential loading for the coming time, this prevent the energy waste due to excessive ice produced by the chiller.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the present invention as claimed. Other advantages and features of the present invention will be apparent from the following description, drawings and claims.
The present invention can be more fully understood by reading the following detailed description of the embodiment, with reference made to the accompanying drawings as follows:
According to an embodiment of the present invention, the central monitoring computer 14 is wiredly or wirelessly connected to the chiller 15 and the air-conditioner 16. The central monitoring computer 14 monitors the current ice amount of the chiller 15 and controls the chiller 15 to perform ice making procedure based on prediction data (namely, prediction result), which will be detailed later. Besides, the central monitoring computer 14 controls the air-conditioner 16 for conducting operations such as operation time, set temperature and fan speed, and controls the operation mode of the air-conditioner 16 based on the target temperature or the target humidity.
According to the present invention, the adjusting system 1 performs a predict procedure based on data associated with a first time (such as today) and data associated with a second time (such as tomorrow) and predicts a potential loading of the air-conditioner 16 during the second time. Moreover, the adjusting system 1 controls the chiller 15 based on the predicted potential loading such that the chiller 15 produces the ice with amount just meeting predicted potential loading and will not produce excessive ice. Therefore, the energy waste of the chiller 15 during ice making procedure can be prevented. In this embodiment, the adjusting system 1 collects the reference data for the prediction procedure through the data collection unit 11. The data collection unit 11 may communicate with the data sources (not shown) to obtain the required reference data for the prediction procedure.
As shown in
According to an embodiment of the present invention, the air-condition scheduler 111 communicates with the air-conditioner 16, the central monitoring computer 14 or a building automation system (BA System, not shown) to obtain the scheduling parameter of the air-conditioner 16 during the first time. The indoor temperature setting module 112 communicates with the air-conditioner 16, the central monitoring computer 14 or at least one sensor (not shown) inside or outside the building to obtain the indoor temperature setting condition for the building during the first time.
The shell-feature collecting module 113 communicates with the central monitoring computer 14 or the BA System to obtain the shell loading factor for the building during the first time. The weather forecasting data collecting module 114 communicates with the central monitoring computer 14 or the BA System, or connects with weather forecasting platform (such as National Weather Service) through network communication such as Internet to obtain the weather forecasting data during the second time (such as hourly outdoor temperature, hourly relative humidity and so on). According to an embodiment of the present invention, the second time is later than the first time. The weather forecasting data collecting module 114 is, for example but not limited, configured to obtain the weather forecasting data during the second time mainly from the weather forecasting platform.
As mentioned above, the air-condition loading predictor 12 may calculate the potential loading of the air-conditioner 16 during the second time by a corresponding algorithm, which will be detailed later, and generate a corresponding prediction result. The adjusting system 1 of the present invention controls the chiller 15 to produce ice based on the prediction result.
The adjusting system 1 of the present invention mainly controls the operation of the air-conditioner 16 during the first time (such as business hour) to provide basic air-conditioning function for a building. During time after the first time and before the second time reaching, the adjusting system 1 obtains the required reference data through the data collection unit 11 and controls the chiller 15 to perform the ice making procedure based on the required data.
As shown in
At the same time, the adjusting system 1 of the present invention obtains the indoor temperature setting condition through the indoor temperature setting module 112 and outputs the indoor temperature setting condition (step S12). More particularly, the indoor temperature setting module 112 calculates the indoor temperature setting condition based on the indoor temperature and extraventricular temperature (also referred to as outdoor temperature) during the first time. According to one embodiment, the indoor temperature setting module 112 calculates the indoor temperature setting condition based on following formula:
T
set=0.48Tin+0.14Tout+8.22
In above formula, Tset is the indoor temperature setting condition, Tin is the indoor temperature of the building during the first time, and Tout is the outdoor temperature of the building during the first time. According to one embodiment, the indoor temperature setting module 112 may obtain the above temperature Tin and Tout through the air-conditioner 16, or one or more sensor inside or outside the building, which is not a limitation for the scope of the present invention. More particularly, when the indoor temperature setting module 112 obtains a plurality of indoor temperatures and outdoor temperatures, the indoor temperature setting module 112 may calculate the average values of the indoor temperatures and the outdoor temperatures for the calculation of the indoor temperature setting condition.
By above formula, the indoor temperature setting module 112 may effectively calculate the indoor temperature setting value optimal to the most comfortableness and best energy saving for the building with given indoor temperature and outdoor temperature.
At the same time, the adjusting system 1 of the present invention calculates the shell loading factor during the first time with the shell-feature collecting module 113 and outputs the shell loading factor (step S14). More particularly, the shell-feature collecting module 113 may calculate the shell loading factor during the first with the E22 energy simulation software, which is free and open software, and the detailed description will not be made here for brevity.
It should be noted that the adjusting system 1 of the present invention directly uses the shell loading factor as one of the predicting parameters when predicting the loading of the air-conditioner 16 during the second time. The prediction result will be more precise due to the consideration of the latent heat in the building.
More particularly, the shell-feature collecting module 113 imports the information such as building materials and geographic reference (such as landmark) into the E22 energy simulation software to establish the shell information for the building. Afterward, the shell-feature collecting module 113 further imports the weather forecasting data at locations around the building into the E22 energy simulation software, and also imports the window-opening frequency of the building during the first time, the window-sunshade factor of the building and the orientation of the building into the E22 energy simulation software such that the E22 energy simulation software can generate the shell loading chart as shown in
Moreover, the adjusting system 1 of the present invention further obtains the weather forecasting data for the location of the building during the second time through the weather forecasting data collecting module 114 and outputs the weather forecasting data for the location of the building during the second time (step S16). The second time is later to the first time. In an embodiment, the second time may be 24 hours period after the first time ends. In another embodiment, the second time may be the first peak hours after the first time ends. In this embodiment, the chiller 15 mainly runs at ice-melting mode during the second time to provide chilled water to the air-conditioner 16
The weather forecasting data is for example, the hourly outdoor temperature and relative humidity during the second time. It should be noted that the adjusting system 1 of the present invention directly uses the relative humidity as one of the predicting parameters when predicting the loading of the air-conditioner 16 during the second time. The prediction result will be more precise due to the consideration of the latent heat in the building.
The air-condition loading predictor 12 is connected to the data collection unit 11. As shown in
Notably, the order for executing the steps 10 to 16 is not fixed. The air-condition scheduler 111, the indoor temperature setting module 112, the shell-feature collecting module 113 and the weather forecasting data collecting module 114 may output the scheduling parameters, the indoor-temperature setting condition, the shell loading factor, and the weather forecasting data based on preset order or preset time, and may output those data at the same time upon instruction. The order for executing those steps is not limited by what is shown in
After step S18, the air-condition loading predictor 12 further provides the prediction result to the energy management platform 13 (step S20), and the energy management platform 13 generates a target ice storage amount (step S22) based on the received prediction result and the energy management platform 13 sends the target ice storage amount, through the central monitoring computer 14, to the chiller 15 (step S24).
In this embodiment, the chiller 15 may determine whether the current ice storage amount is larger than the target ice storage amount after receiving the target ice storage amount (step S26). In this embodiment, the chiller 15 performs the ice making procedure at the moment after the first time and before the second time. Therefore, the “current ice storage amount” in above description is referred to as the remaining number of ices in the chiller 15 after the first time.
If the current ice storage amount in the chiller 15 is larger than the target ice storage amount (this means that the ice tank 151 has ice sufficient for the use of the air-conditioner 16 during the second time), then the chiller 15 does not need to adjust the ice storage amount and does not need to perform ice making procedure. On the contrary, if current ice storage amount in the chiller 15 is not larger than the target ice storage amount, the chiller 15 adjusts the ice storage amount required for the second time based on the target ice storage amount (step S28). After the step S28, when the chiller 15 enters the ice storing mode (namely, leaving the peak hour and entering the off-peak hour), the chiller 15 performs the ice making procedure based on the target ice storage amount such that the ice storage amount of the ice tank 151 may reach the target ice storage amount.
It should be noted that the target ice storage amount is a predicted value and may have considerable deviation with the actual need. To prevent the ice shortage problem of the air-conditioner 16 due to prediction error, in the step S26, the chiller 15 may determine whether the current ice storage amount is larger than 1.1 times of the target ice storage amount. Moreover, the chiller 15 adjusts the ice storage amount to 1.1 times of the target ice storage amount when the current ice storage amount is not larger than 1.1 times of the target ice storage amount. Therefore, the ice shortage problem due to prediction error can be prevented.
The about mentioned 1.1 times is just an example, the choice of 1.1 times is intended to prevent ice shortage problem without over-wasting the energy of the chiller 15. The ice storage amount of the chiller 15 is not limited to 1.1 times of the target ice storage amount. In other embodiments, the adjusting system 1 of the present invention may set the ice storage amount of the chiller 15 to be 1.2 times or 1.3 times of the target ice storage amount, which is not limitation to the present invention.
As shown in
In this embodiment, the air-condition loading predictor 12 may calculate the extraventricular enthalpy value based on the weather forecasting data (step S182). It should be noted that the weather forecasting data comprises the hourly extraventricular temperature and relative humidity for the location of the building during the second time. With the consideration of both the temperature and the humidity, and converting the data of temperature/humidity into enthalpy value, the air-condition loading predictor 12 may use the latent heat of the building as one of the prediction parameters during the prediction procedure, thus obtain more precise prediction result.
In this embodiment, in the step S182, the air-condition loading predictor 12 calculates the partial pressure during the second time according to the following formula 1.
P
S=(6.1164*10(7.591386*T/T+240.7263)))/10 Formula 1
In above formula 1, Ps is the predicted partial pressure during the second time, T is the hourly extraventricular temperature according to the weather forecasting data.
The air-condition loading predictor 12 further calculates a humidity ratio during the second time according to the following formula 2.
ω=(0.6219* PS* RH/100)/(101.325−(PS* RH/100)) Formula 2
In above formula 2, ω is the predicted humidity ratio during the second time, Ps is the predicted partial pressure during the second time, RH is the relative humidity according to the weather forecasting data.
The air-condition loading predictor 12 further calculates an extraventricular enthalpy value during the second time according to the following formula 3.
H
oa
=T*(1.01+1.89*ω)+2500*ω Formula 3
In above formula 3, Hoa is the predicted extraventricular enthalpy value (kJ/kg) during the second time, T is the hourly extraventricular temperature according to the weather forecasting data, and ω is the predicted humidity ratio during the second time.
In this embodiment, the air-condition loading predictor 12 first predicts the partial pressure during the second time based on the hourly extraventricular temperature in the weather forecasting data, then predicts the humidity ratio during the second time based on the partial pressure and the relative humidity in the weather forecasting data, and finally predicts the extraventricular enthalpy value based on the humidity ratio and the hourly extraventricular temperature in the weather forecasting data.
Refer also to
Referred back to
P
S=(6.1164*10(7.591386*T/T+240.7263)))/10 Formula 4
In above formula 4, Ps is the predicted partial pressure during the first time and T is indoor-temperature setting condition.
The air-condition loading predictor 12 further calculates the humidity ratio during the first time according to the following formula 5.
ω=(0.6219*PS*65/100)/(101.325−(PS* 65/100)) Formula 5
In above formula 5, ω is the humidity ratio during the first time, Ps is the partial pressure during the first time. In this embodiment, the indoor humidity in formula 5 is preset to be 65 due to smaller variation of indoor humidity.
The air-condition loading predictor 12 further calculates the indoor enthalpy value during the first time according to the following formula 6.
H
indoor
=T* (1.01+1.89*ω)+2500*ω Formula 6
In above formula 6, Hindoor is the indoor enthalpy value during the first time, ω is the humidity ratio during the first time, and T is indoor-temperature setting condition. In this embodiment, the air-condition loading predictor 12 first calculates the partial pressure during the first time based on the indoor-temperature setting condition, then calculates the humidity ratio during the first time based on the partial pressure and the preset humidity value (65 in this embodiment), and finally calculates the indoor enthalpy value based on the humidity ratio and the indoor-temperature setting condition.
With reference back to
More particularly, the air-condition loading predictor 12 calculates the extraventricular-induced loading according to the following formula 7.
η*ρ*m*(Hoa−40.13)/3600* Topen Formula 7
In above formula 7, η is the equipment efficiency of the air-conditioner 16, ρ is air density (kg/m3), m is wind amount (CMH), Hoa is the calculated extraventricular enthalpy value and Topen is the scheduling parameter of the air-conditioner 16. It should be noted that η may be the standard equipment efficiency of the air-conditioner 16, which is marked on casing of the air-conditioner 16, while ρ is standard air density, namely, 1.2 (kg/m3), but above examples are not limitation of the present invention.
With reference back to
Hoa−Hindoor Formula 8
Afterward, the air-condition loading predictor 12 calculates the potential air-condition loading of the air-conditioner 16 during the second time based on the extraventricular-induced loading, the enthalpy difference and the shell loading factor, and then generates the corresponding prediction result (step S190). In this embodiment, the air-condition loading predictor 12 mainly predicts the potential air-condition loading of the air-conditioner 16 based on the extraventricular-induced loading, the enthalpy difference and a plurality of shell loading factors relevant to different orientations (such as four orientations east, west, south and north) of the building. Therefore, the unprecise prediction of convention air-conditioner for the potential loading, which is caused by sole consideration of sensible heat, can be improved.
Refer to
As shown in
If the second time has not reached and the current ice storage amount of the chiller 15 does not reach the target ice storage amount (or does not reach 1.1 times of the target ice storage amount), the energy management platform 13 controls, through the central monitoring computer 14, the chiller 15 to operate in an ice storing mode and the ice making procedure is executed continually in the ice storing mode (step S44).
If the second time reaches and the current ice storage amount of the chiller 15 also reaches the target ice storage amount, the energy management platform 13 controls, through the central monitoring computer 14, the chiller 15 to switch its operation from ice storing mode to ice melting mode (step S46). In the ice melting mode, the chiller 15 supplies chilled water to the started air-conditioner 16 to realize the temperature adjusting function of the air-conditioner 16.
After the chiller 15 enters the ice melting mode, the adjusting system 1 keeps determining, through the energy management platform 13 or the central monitoring computer 14, whether the second time ends (step S48). If the second time ends (such as off-work hour or off-peak hour), it means that the chiller does not need to perform the ice melting mode. At this time, the energy management platform 13 controls, through the central monitoring computer 14, the chiller 15 to switch its operation from ice melting mode to ice storing mode or standby mode (step S50). Therefore, the adjusting system 1 waits for the preset ice storing time and then performs the steps shown in
Before the second time ends, the adjusting system 1 keep determining, through the energy management platform 13 or the central monitoring computer 14, whether the current ice storage amount of the chiller 15 is below a waring threshold (step S52). In one embodiment, the warning threshold is, for example but not limited to, 3% or 5% or the target ice storage amount.
More particularly, the energy wasted by the chiller 15 to re-execute the ice making procedure is larger when the remaining ice in the ice tank is fewer. To prevent energy waster, the energy management platform 13 controls, through the central monitoring computer 14, the chiller 15 to leave the ice melting mode (step S54) if the current ice storage amount is below the waring threshold (even the second time does not pass). The energy waste used for the next ice making procedure can be prevented.
By above procedure, the adjusting system 1 of the present invention can predict the potential loading of the air-conditioner 16 for the coming time (such as the working hour tomorrow) based on both the sensible heat and the latent heat. The adjusting system 1 of the present invention controls the chiller to produce ice with number corresponding to the prediction result to prevent the energy waste in the ice making procedure.
Although the present invention has been described with reference to the preferred embodiment thereof, it will be understood that the present invention is not limited to the details thereof. Various substitutions and modifications have been suggested in the foregoing description, and others will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the present invention as defined in the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 107136027 | Oct 2018 | TW | national |
