Method for Monitoring the Energy Content of a Water Storage Tank System

Abstract

A method of controlling a heat up of a hot water tank, comprising a tank, which contains water and receives incoming cold-water at a cold-water inlet and outputs heated water through a heated water outlet, the method comprising: heating the water in the tank depending on a thermal energy content calculated as a function of an actual incoming cold-water temperature measured by a cold-water temperature sensor, when a tapping event is identified. A water tank heating device and a controller system for controlling a heat up of a hot water tank depending on a thermal energy content calculated as a function of an actual incoming cold-water temperature.

1 . A method of determining a thermal energy content of a hot water tank device, the hot water tank device comprising a tank, a cold-water inlet, a heated water outlet, a cold-water temperature sensor, a heating device and a controller component,
 the tank containing water, wherein the tank receives incoming cold-water at the cold-water inlet and outputs heated water through the heated water outlet when a tapping event occurs,   the heated water outlet being located in an upper portion of the tank and the cold-water inlet being located in a lower portion of the tank with the heating device being thermally coupled to water in between the cold-water inlet and the heated water outlet,   the cold-water temperature sensor being arranged in the lower portion of the tank configured to determine a temperature of the water in vicinity of the cold-water inlet,   wherein the water within the tank is heated by operation of the heating device thermally coupled to the water, the operation of the heating device is controlled by said controller component, the method comprising:   measuring, using the cold-water temperature sensor, successive incoming cold-water temperatures in successive cold-water temperature measurements measured in a defined measuring rate,   detecting, by said controller component, a beginning of a tapping event when a difference of two successive incoming cold-water temperatures of two successive cold-water temperature measurements exceeds a predetermined first temperature difference threshold,   measuring, using the cold-water temperature sensor, successive incoming water temperatures during an adequate time period after the beginning of said tapping event,   deriving, using the controller component, the actual incoming water temperature as an average of the incoming water temperatures measured during said adequate time period,   determining, using the controller component, the thermal energy content of the hot water tank device as a function of said derived actual incoming cold-water temperature.   
     
     
         2 . The method according to  claim 1 , wherein said adequate time period starts when a difference of two successive incoming cold-water temperatures of two successive cold-water temperature measurements is below a second temperature difference threshold. 
     
     
         3 . The method according to  claim 1 , wherein said adequate time period ends after a predetermined period of time has elapsed or at or after an end of said tapping event. 
     
     
         4 . The method according to  claim 1 , wherein the step of measuring successive incoming cold-water temperatures in successive cold-water temperature measurements with said cold-water temperature sensor during said adequate time period comprises storing said successive cold-water temperatures in a storing unit of the controller component. 
     
     
         5 . The method according to  claim 1 , further comprising:
 determining, by said control unit, a validity of subsequent incoming water temperature measurements during said adequate time period, wherein said subsequent cold-water temperature measurements are valid if a temperature difference between the two subsequent cold-water temperature measurements is lower than a third temperature difference threshold.   
     
     
         6 . The method according to  claim 1 , the hot water tank device further comprising a second temperature sensor mounted to said tank, the method further comprising:
 measuring a tank temperature using the second temperature sensor, which is related to a thermal energy content, and output a tank temperature signal representative of said tank temperature with a tank temperature sensor mounted to said tank.   
     
     
         7 . The method according to  claim 1 , further comprising a step of transmitting, using a ripple control transmitter device in signal communication with the controller component, an energy content signal indicative of the determined thermal energy content. 
     
     
         8 . The method according to  claim 7 , further comprising a step of receiving, using a ripple control tuner in signal communication with the controller component, a signal for activating the heating device in response to the energy content signal. 
     
     
         9 . A hot water tank device, the hot water tank device comprising a tank, a cold-water inlet, a heated water outlet, a cold-water temperature sensor, a heating device and a controller component,
 the tank containing water, wherein the tank receives incoming cold-water at the cold-water inlet and outputs heated water through the heated water outlet when a tapping event occurs,   the heated water outlet being located in an upper portion of the tank and the cold-water inlet being located in a lower portion of the tank with the heating device being thermally coupled to water in between the cold-water inlet and the heated water outlet,   the cold-water temperature sensor being arranged in the lower portion of the tank configured to determine a temperature of the water in vicinity of the cold-water inlet,   wherein the water within the tank is heated by operation of the heating device thermally coupled to the water, the operation of the heating device is controlled by said controller component,   the cold-water temperature sensor being configured to successively measure incoming cold-water temperatures in successive cold-water temperature measurements in a defined measuring rate,   the controller component being configured to determine a beginning of a tapping event when a difference of two successive incoming cold-water temperatures of two successive cold-water temperature measurements exceeds a predetermined first temperature difference threshold,   the cold-water temperature sensor being further configured to successively measure incoming water temperatures during an adequate time period after the beginning of said tapping event,   the controller component being configured to derive the actual incoming water temperature as an average of the incoming water temperatures measured during said adequate time period, and   the controller component being configured to determine the thermal energy content of the hot water tank device as a function of said derived actual incoming cold-water temperature.   
     
     
         10 . A controller system for controlling a heat up of a hot water tank, comprising
 a cold-water temperature sensor configured to be attached at a place of a tank, which contains water and comprises a water inlet configured for receiving incoming cold-water and a water outlet configured for allowing water heated to exit,   wherein said cold-water temperature sensor is configured to measure an actual incoming cold-water temperature and to output an actual cold-water temperature signal representative of said actual incoming cold-water temperature and   a control unit comprising microprocessor software integrated in an electronic device,   wherein said control unit is configured to receive said actual cold-water temperature signal transmitted by said cold-water temperature senor,   wherein said control unit is configured to identify a tapping event and to control a heating device when said tapping event is identified in order to heat water in the tank depending on a thermal energy content calculated as a function of an actual incoming cold-water temperature measured by said cold-water temperature sensor.   
     
     
         11 . A method of controlling a heat up of a hot water tank having a control unit with a receiver interface circuit, a control circuit arrangement and a transmitter interface circuit, the method comprising the steps of:
 measuring a first tank temperature of said hot water tank with a temperature sensor mounted to said hot water tank;   receiving, by said receiver interface circuit, a first tank temperature signal generated and transmitted by said temperature sensor, which represents said first tank temperature;   generating, by said control circuit arrangement, an activation signal to activate a heating device, when said control circuit arrangement calls for heat;   feeding an actual incoming cold-water temperature signal into said control circuit arrangement, wherein said actual incoming cold-water temperature signal represents an actual incoming cold-water temperature of cold-water, which flows into said hot water tank;   generating, by said control circuit arrangement, a parameter based on said actual incoming cold-water temperature signal;   measuring a second tank temperature of said hot water tank with said temperature sensor after said incoming cold-water flowed into said hot water tank, wherein said second tank temperature is related to a thermal energy content of said hot water tank;   receiving, by said receiver interface circuit, a second tank temperature signal generated and transmitted by said temperature sensor, which represents said second tank temperature;   modifying, by said control circuit arrangement, said parameter based on said second tank temperature signal;   performing, by said control circuit arrangement, a comparison of a set point value with said parameter, which is modified based on said second tank temperature signal;   processing, by said control circuit arrangement, said activation signal depending on said comparison; and   transmitting, by said transmitter interface circuit to a receiver interface circuit of a heating device, said activation signal, which is processed depending on said comparison.   
     
     
         12 . The method according to  claim 11 , further comprising:
 calculating, by said control circuit arrangement, an exact value of said thermal energy content as a function of a reference mass and said parameter, which is modified based on said second tank temperature signal,   wherein the step of generating, by said control circuit arrangement, said activation signal depends on at least one of a) whether said exact value is lower than said set point value and b) on an amount of said exact value,   wherein said control circuit arrangement generates said activation signal when said exact value is lower than the set point value.   
     
     
         13 . The method according to  claim 11 ,
 wherein the step of generating, by said control circuit arrangement, said activation signal depends on whether said amount of said exact value is lower than a specified value of thermal energy content,   wherein said control circuit arrangement generates said activation signal when said amount of said exact value is less than a specified value of thermal energy content.   
     
     
         14 . The method according to  claim 11 , further comprising:
 calculating, by said control circuit arrangement, an exact value of said thermal energy content by multiplying a reference mass parameter by a temperature rise value,   wherein said temperature rise value is a difference between said set point value and said incoming cold-water temperature,   wherein the step of generating, by said control circuit arrangement, said activation signal depends on said exact value.   
     
     
         15 . The method according to  claim 11 , further comprising:
 comparing, by said control circuit arrangement, said actual incoming cold-water temperature represented by said actual cold-water signal fed into said control circuit arrangement with a previous stored water temperature represented by a previous stored water temperature signal, which is stored in a storage circuit of said control circuit arrangement;   updating, by said control circuit arrangement, said previous stored water temperature signal, if said actual incoming cold-water temperature differs from said previous stored water temperature; and   utilizing said stored water temperature signal, which is updated, for the step of generating, by said control circuit arrangement, said parameter,   wherein the step of updating, by said control circuit arrangement, said previous stored water temperature signal, depends on whether said actual incoming cold-water temperature is lower than said stored water temperature,   wherein said control circuit arrangement updates said previous stored water temperature signal if said actual incoming cold-water temperature is lower than said previous stored water temperature.   
     
     
         16 . The method according to  claim 11 ,
 wherein the step of feeding said incoming cold-water temperature signal into said control circuit arrangement, comprises the steps:   measuring said actual incoming cold-water temperature with a cold-water temperature sensor located in said hot water tank close to a water inlet; and   receiving, by said receiver interface circuit, said actual incoming cold-water temperature signal generated and transmitted by said cold water temperature sensor, which represents said actual incoming cold-water temperature.   
     
     
         17 . The method according to  claim 11 , further comprising:
 comparing a last measured incoming cold-water temperature with a previously measured incoming cold-water temperature to calculate a difference; and   activating a second timer, which initiates detecting said actual incoming cold-water temperature or successive incoming cold-water temperatures with a time base, when said difference is lower than a first defined difference value,   after said second timer is started, detecting successive incoming cold-water temperatures periodically for a minimum duration of more than 10 seconds and putting each incoming cold-water temperature in a register;   performing, by said control circuit arrangement, a comparison of said successive incoming cold-water temperatures putted in said register;   determining, by said control circuit arrangement, a validity of said successive cold-water temperature measurements depending on a difference resulting from said comparison, wherein said successive cold-water temperature measurements are valid if said difference is lower than a second defined difference value;   averaging, by said control circuit arrangement, the successive incoming cold-water temperatures putted in said register to obtain an averaged incoming cold-water temperature;   comparing, by said control circuit arrangement, said averaged incoming cold-water temperature with a previous stored averaged water temperature represented by a previous stored averaged water temperature signal, which is stored in a storage circuit of said control circuit arrangement; and   updating, by said control circuit arrangement, said previous stored averaged water temperature signal, if a difference between said averaged incoming cold-water temperature and said previous stored averaged water temperature is more than 2° C.,   wherein the step of updating, by said control circuit arrangement, said previous stored water temperature signal comprising a simple moving averaging process.   
     
     
         18 . The method according to the  claim 11 , further comprising:
 providing energy needs of at least one hot water tank to an energy supplier or transmitting energy needs of at least one hot water tank to a utility company.   
     
     
         19 . The method according to  claim 11 ,
 wherein a utility company sorting consumers into different energy demand classes in order to stabilize a voltage to keep said voltage constant, a frequency to keep said frequency constant, or both, of an electric grid.   
     
     
         20 . The method according to  claim 19 ,
 wherein the heating device comprises a receiver interface circuit to receive a remote control command, which is generated and transmitted by a utility company,   wherein the method comprises the step of receiving, by said receiver interface circuit of the heating device, said remote control command generated and transmitted by said utility company.