Abstract:
A portable electrical energy power node is provided. The power node includes first and second input power terminals and first and second output power terminals. The input power terminals are adapted for receiving a source of electrical power and the output terminals are adopted for connecting to a load. A first power line connects the first input terminal to the first output terminal, a second power line connects the second input terminal to the input side of a circuit interrupter and a third power line connects the output side of the circuit interrupter to the second output terminal. The circuit interrupter selectively interrupts the connection between the second input terminal and the second output terminal in accordance with a fault sensor and a control unit.

Description:
TECHNICAL FIELD 
       [0001]    The present invention generally relates to the field of energy use and more particularly, is directed to a smart power node that can be installed at any location in an electric power distribution system for monitoring and controlling electrical energy consumption. 
       BACKGROUND 
       [0002]    In many cases, an electric load is connected directly to a branch circuit which is protected by an upstream device, such as a circuit breaker in a power distribution panel. More than one load usually is connected to the same branch circuit. Thus, when a fault condition is detected and the breaker trips, all of the connected loads lose power. Loss of power to all of the loads often creates substantial hardship to users if the fault is not quickly corrected or isolated. 
         [0003]    In other cases, electric loads are connected to the edge of a power distribution system through power extenders, such as extension cords, power strips and power adapters. When connected in this manner, loads are even further removed from the upstream branch circuit protection device, thereby increasing the likelihood that a fault condition elsewhere in the system will adversely affect the load. 
         [0004]    Prior art power extenders and edge connected loads are not easily monitored and independently controlled by devices that reside on a branch circuit or within a power distribution panel. Thus, there is a need in the art for such monitoring and control. Moreover, the monitoring and control capability should easily be deployable anywhere within a power distribution system, and especially at it edges, on an ad hoc basis when and where needed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    The novel features of the present invention are set out with particularity in the appended claims, but the invention will be understood more fully and clearly from the following detailed description of the invention as set forth in the accompanying drawings in which: 
           [0006]      FIG. 1  is a block diagram of a smart power node in accordance with one embodiment of the present invention; 
           [0007]      FIG. 2  is block diagram of a plurality of smart power nodes formed into a network in accordance with the present invention; 
           [0008]      FIG. 3  is a block diagram of a monitor and controller used in a smart power node in accordance with the present invention; 
           [0009]      FIG. 4  is a flow chart illustrating the operation of the monitor and controller illustrated in  FIG. 3 ; 
           [0010]      FIGS. 5 and 6  is a flow chart illustrating the operation of the smart power node network illustrated in  FIG. 2 ; 
           [0011]      FIG. 7  is a block diagram of one embodiment of a Master Control System for smart power nodes in accordance with the present invention; 
           [0012]      FIG. 8  is block diagram of another embodiment of a smart power node having a plurality of circuit interrupters in accordance with the present invention; and 
           [0013]      FIG. 9  is block diagram of a further embodiment of a smart power node having a plurality of environmental sensors in accordance with the present invention. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0014]    A preferred embodiment of the present invention will be described with reference to the figures. 
         [0015]      FIG. 1  is a block diagram of one embodiment of the present invention in the form of a smart power node  100 . In this embodiment, the current and voltage from a power source is monitored for certain conditions which can be used to determine whether power to an attached load should be interrupted. 
         [0016]    The data obtained from monitoring source power lines can also be communicated to a central location, such as the Master Control System shown in  FIG. 7 , for retention and/or analysis. 
         [0017]    Such analysis might include waveform analysis relating to the electronic signature of connected loads. The signature information may be shared with other systems for further analysis and historical comparisons. 
         [0018]    Depending on how power node  100  is configure, as will be described with respect to  FIG. 2 , power node  100  may simply be a monitoring station reporting data to the Master Control System and/or be under the control of the Master Control System. 
         [0019]    Power node  100  can be deployed anywhere in a power distribution system where monitoring and/or control of connected loads is desired, including within electrical power extenders such as extension cords, power strips, power adapters and the like. Power node  100  can operate independently or operate within a network with other power nodes as will be described with respect to  FIG. 2 . 
         [0020]    As illustrated in  FIG. 1 , electrical power from a power source is connected to power lines  103  and  104  of power node  100  via electrical contacts  101  and  102 . Circuit interrupter  105  selectively breaks continuity of power line  104  to electrical contact  107 . Contacts  107  and  108  allow an electric load to be connected to the power node. 
         [0021]    Interrupter  105  may be formed of mechanical components which are activated by a solenoid that can be triggered by an electrical signal as is known in the art. Interrupter  105  may also be formed of a solid-state device, such as a triac, as also known in the art. In the present invention, the operation of interrupter  105  is controlled by a control trigger signal  109  from Monitor/Controller  110  in a manner described below with reference to  FIG. 3 . 
         [0022]    Monitor/Controller  110  is connected to power lines  103  and  104  via connection points  111  and  112 . 
         [0023]      FIG. 2  is block diagram of a network architecture illustrating a plurality of smart power nodes  100 A- 100 D which are integrated into an electric power control network. In accordance with the present invention, the number of smart power nodes in the network can be as many as required. 
         [0024]      FIG. 2  depicts in dashed lines the signal and data communication path between various devices on the network. Each power node receives it electrical power from various sources as may be determined by the user. For example, smart power node  100 A receives its power from power line  201  through smart breaker  202  which may be located in a power panel. Thus, contacts  101  and  102  of the power node, as shown in  FIG. 1 , may be formed in the manner of electrical contact blades that are adapted to be plugged into a conventional wall receptacle as one of ordinary skill in the art would know. Power node  100 A monitors and controls the power supplied to one or more electrical loads  203 . 
         [0025]    Smart power node  100 B receives its power from smart power node  100 A and monitors and controls the power supplied to one or more electrical loads  204 . 
         [0026]    Smart power node  100 C receives its power from power source  205 , which can be one of any number of power sources. Power node  100 C monitors and controls the power supplied to one or more electrical loads  206 . 
         [0027]    Smart power node  100 D receives its power from power source  207 , which can also be one of any number of power sources. Power node  100 D monitors and controls the power supplied to one or more electrical loads  208 . 
         [0028]    Each smart power nodes  100 A- 100 D can independently be configured for their particular application and use. For example, power node  100 B may be configured only to monitor voltage, current and/or fault conditions with respect to power line  109  but may not have the ability to interrupt power to load  204  when a fault condition is detected. The interrupt function may be the responsibility of power node  100 A when it detects the same fault. 
         [0029]    As illustrated by dashed lines in  FIG. 2 , power nodes  100 A- 100 D may communicate monitoring data to a hub  210 , which can forward the data to server  211  which might reside on a private network associated with the building or structure that is serviced by the electrical system. 
         [0030]    The data can be analyzed for a number of purposes using application software running on server  211 . The results of the analysis can be used to configure each of power nodes  100 A- 100 D for their particular purpose and location. Server  211  may also forward the data on to Internet server  212  for wider distribution and/or further analysis, alone or in combination with data provided to server  212  from other systems. 
         [0031]    Server  212  allows a stakeholder associated with the building to log into server  212  with appropriate credentials as one skilled in the art would know and to review the monitored data. The same can be done with respect to server  211  using a virtual private network connection. 
         [0032]      FIG. 2  also illustrates IoT Devices  214  and  215 . The Internet of Things (IoT) is the term used to describe a developing concept where common objects will have network connectivity and can share data with other objects and with the outside world. Smart power nodes  100 A- 100 D follows this concept. 
         [0033]      FIG. 3  is a block diagram of one embodiment of Monitor/Controller  110  shown in  FIG. 1 . Corresponding reference numbers from  FIG. 1  are retained in  FIG. 3  where appropriate. 
         [0034]    Monitor/Controller  110  includes GFCI/AFCI sensors  301  and voltage/current sensor  302  which are coupled to circuit interrupter  105 . GFCI/AFCI sensor  301  is configured to provide fault sense signals to CPU  315  over the CPU Signal And Data BUS (hereafter, “CPU BUS”) via High Signal-to-Noise ratio, Low Impedance Circuitry (SNR)  303 . SNR  303  improves the performance of fault detection for smart power node  100 . 
         [0035]    Voltage/current sensor  302  provides voltage and current signals to CPU  315  over the CPU BUS. With the voltage and current signals from voltage/current sensor  302 , and fault sense signals from the GFCI/AFCI sensor  301 , CPU  315  can identify faults, including overload faults caused by the attached load, AFCI faults and GFCI faults. 
         [0036]    When a fault occurs, CPU  315  stores the fault type and the time of its occurrence in fault type and time register  321 . CPU  315  can also can be programmed with the conditions upon which interrupter  105  will be triggered in response to detected faults. These conditions are stored in fault trigger condition register  322 . Initially, default trigger conditions can be stored in register  322  and then changed as required. 
         [0037]    Monitor/Controller  110  also includes a real time clock  318  which assist in keeping track of timed events, such as the time of day, time of a particular fault and elapsed time since a last fault. 
         [0038]    If CPU  315  identifies a fault, one or more of three events can occur. 
         [0039]    First: CPU  315  can output trigger signal  309  to circuit interrupter  105  to break continuity of power line  104  to contact  107 . CPU  315  can also trigger a visual indication of the fault condition such as by illuminating an LED light  304  or sounding an audio alarm through speaker  307  or other audio device. LED  304  can also be a multi-color device, each color indicating the type of fault condition. The audio alarm may also be in the form of a synthesized human voice from voice circuit  309  in accordance with the nature and severity of the fault. 
         [0040]    Monitor/Controller  110  continuously monitors line  103  and  104  and status indicators are updated as required. Thus, should the fault condition clear, the continuity of line  104  to the attached load can be restored by CPU  315  sending an appropriate signal to circuit interrupter  105 . In some circumstances, however, continuity may not be restored until other conditions are satisfied, such as by the intervention of a human pressing a manual reset button. 
         [0041]    Second: Instead of triggering circuit interrupter  105  directly to break the continuity of power line  104  to contact  107 , CPU  315  may cause all, or selected fault signals, to be send to the Master Control System  216  illustrated in  FIG. 2  via Power-Line Communications Interface  310  for processing and disposition. Alternative communications technologies may also be used, such as LAN/WiFi interface  311 , or Bluetooth  309 . Alternative communications technologies also include an RS-232 serial line, Zibgee, XBee and Z-Wave. 
         [0042]    In situations where security of the data is of concern, the data may be encrypted using encryption/decryption module  323  in accordance with one of a number of encryptions methods and routines as is known in the art. 
         [0043]    Upon receiving the fault signals, the Master Control System may response by sending a command to CPU  315  to break the continuity of power line  104  or continue continuity. 
         [0044]    Third: CPU  315  may trigger circuit interrupter  105  to break the continuity of power line  104  to contact  107  as well as send the fault signal to Master Control System  216  illustrated in  FIG. 2 . 
         [0045]    Monitor/Controller  110  may also include self-test circuitry  305  coupled to CPU  315  via the CPU BUS. Self-test circuitry  305  enables test signals to be sent to and from the Master Control System via, for example, Power-Line Communications Interface  310  to test the overall functionality of smart power node  100 . 
         [0046]    Self-test circuitry  305  may include a test button that can be pressed in order to initiate the self-test or a self-test may be initiated by the Master Control System. 
         [0047]    CPU  315  is used for executing computer software instructions as is known in the art. In addition to the elements described above, CPU  315  is coupled to a number of other elements via the CPU BUS. 
         [0048]    These elements include RAM  312  (Random Access Memory) which may be used to store computer software instructions, ROM  314  (Read Only Memory) which may also be used to store computer software instructions, and Non Volatile Memory  316  which may be used to store computer software instructions as well. 
         [0049]    Electronic Address Module  317  provides a unique electronic address for power node  100 . Thus, power node  100  can be uniquely addressed by the Master Control System. The address stored in Electronic Address Module  317  is implemented as a unique series of numbers. An example of such an addressing scheme is an Internet Protocol address based on IPv4 or IPv6 as is known in the art. The address can also be static or a dynamic IP address. 
         [0050]    Monitor/Control  110  may also include a packet switch network hub  319  which can communicate with a local or remote server through, for example, Power-Line Communications Interface  310 . 
         [0051]    As also shown in  FIG. 3 , battery  324  is used to provide electrical power to Monitor/Controller  110  when smart power node  100  is not receiving power from a power source. 
         [0052]      FIG. 4  is a flow chart  400  that illustrates the operation of Monitor/Control  110  as depicted  FIG. 3 . 
         [0053]    In step  401 , the fault trigger conditions for smart power node  100  are initialized and stored in fault trigger condition register  322 . 
         [0054]    In step  402 , fault type and time register  321  is reset to indicate no active or previous fault conditions. 
         [0055]    In step  403 , is decision is made whether a fault signal is present from GFCI/AFCI sensor  301  or from voltage/current sensor  302 . If a fault signal is present, the process continues to step  404 . If no fault signal is present, the process loops so that step  403  can make another decision whether a fault signal is present. 
         [0056]    In step  404 , the fault signal is stored in fault type and time register  321 . 
         [0057]    In step  405 , a decision is made whether the fault signal is an over current fault. If yes, circuit interrupter  105  is trigger to interrupt power to contact  107  in step  406  and the over current fault condition previously stored in fault type and time register in step  404  is cleared in step  407 . The process then loops back to step  403 . 
         [0058]    If step  405  determines that the fault condition is not an over current fault, a decision is made in step  408  whether the fault is an AFCI fault. 
         [0059]    In the case of an AFCI fault, a decision is made in step  409  whether circuit interrupter  105  should be triggered based solely on the presence of the AFCI fault condition. If yes, interrupter  105  is triggered in step  410 , fault type and time registered  321  is cleared of the AFCI fault in step  412  and the process loops back to step  403 . 
         [0060]    If step  409  determines that circuit interrupter  105  should not be triggered on the basis of the AFCI fault alone, a decision is made whether interrupter  105  should be triggered based on an addition fault condition. One example of an addition fault condition, as depicted in step  411 , is that a prior GFCI fault occurred within a predetermined time “x” of the current AFCI fault condition. Other fault conditions can be used as well as those of ordinary skill in the art will understand. 
         [0061]    If the conditions for triggering circuit interrupter  105  are satisfied in step  411 , interrupter  105  is triggered in step  414 , fault type and time registere  321  is cleared of the AFCI and GFCI faults in step  415  and the process loops back to step  403 . If the conditions for triggering interrupter  105  are not satisfied in step  411 , the process loops back to step  403 . 
         [0062]    If step  408  determines that the fault is not an AFCI fault, the process continues to step  416 . In step  416 , a decision is made whether the fault is a GFCI fault. 
         [0063]    In the case of a GFCI fault, a decision is made in step  417  whether circuit interrupter  105  should be triggered based solely on the presence of the GFCI fault condition. If yes, interrupter  105  is triggered in step  418 , fault type and time registered  321  is cleared of the GFCI fault in step  420  and the process loops back to step  403 . 
         [0064]    If step  417  determines that circuit interrupter  105  should not be triggered on the basis of the GFCI fault alone, a decision is made whether interrupter  105  should be triggered based on an addition fault condition. An example of an addition fault condition, as depicted in step  419 , is that a prior AFCI fault occurred within a predetermined time “x” of the current GFCI fault condition. Other fault conditions can be used as well as those of ordinary skill in the art will understand. 
         [0065]    If the conditions for triggering circuit interrupter  105  are satisfied in step  419 , interrupter  105  is triggered in step  421 , fault type and time registered  321  is cleared of the AFCI and GFCI faults in step  422  and the process loops back to step  403 . If the conditions for triggering interrupter  105  are not satisfied in step  419 , the process then loops back to step  403 . 
         [0066]    If step  416  determines that the current fault is not a GFCI fault, the process loops back to step  403 . 
         [0067]      FIGS. 5 and 6  is a flow chart  500  that illustrates the operation of smart power node  100  when used in a network configuration, such as illustrated in  FIG. 2 . 
         [0068]    In step  501 , a decision is made whether a fault signal is present. If yes, the process proceeds to step  504  where a decision is made whether circuit interrupter  105  should be triggered based on this fault signal. If yes, interrupter  105  is triggered in step  505  and the process continues to step  508 . Otherwise, the process continues directly to step  508   
         [0069]    In step  508 , a decision is made whether a visual fault alarm should be triggered based on this fault. If yes, the visual alarm is triggered in step  509  and the process continues to step  512 . Otherwise, the process continues directly to step  512 . 
         [0070]    In step  512 , a decision is made whether an audio fault alarm should be triggered based on this fault. If yes, an audio alarm is triggered in step  514  and the process continues to step  517 . Otherwise, the process continues directly to step  517 . 
         [0071]    In step  517 , a decision is made whether the fault should be reported to the Master Control System. If yes, the fault is reported to the Master Control System in step  518  and the process continues to step  601  in  FIG. 6 . Otherwise, the process continues directly to step  501  in  FIG. 5 . 
         [0072]    In step  601 , a decision is made whether a power source voltage is present as indicated by the signal from voltage/current sensor  302  in  FIG. 3 . If yes, the process continues to step  603  where a decision is made whether this is a cold start as if smart power node  100  is connected to a power source for the first time. If yes, a dynamic IP address is obtained from the Master Control System in step  605 . Otherwise, the process loops back to step  501  in  FIG. 5 . If a static IP has already been assigned to smart node  100  there will not be a need to obtain a dynamic IP in step  605   
         [0073]    In step  607 , the operating parameters for smart power node  100  are obtained from the Master Control System and in step  609  real time clock  318  in  FIG. 3  is set. The operating parameters may also be obtained from private network server  211  or Internet server  212  illustrated in  FIG. 2 . Smart power node  100  may also be preconfigured with default operating parameters. 
         [0074]    The process then proceeds to step  610  where a ready light, for example, a green light from LED light  304  in  FIG. 3 , is illuminated to indicate that power node  100  is in a ready state. 
         [0075]    The process then continues in step  501  in  FIG. 5 . 
         [0076]    If in step  601 , a determination is made that no power source voltage is present, the process continues to step  602 . 
         [0077]    In step  602 , a decision is made whether the time since the power source voltage was present is greater than, for example, one minute. If no, the process loops back to step  601 . Otherwise, the process continues to step  604 . 
         [0078]    In step  604 , “a no branch voltage” visual indication is provided by LED light  304 , as for example, by lighting a red light not ready light. The process continues to step  606 . 
         [0079]    In step  606 , a decision is made whether the status condition of power node  100  should be reported to the Master Control System. If yes, the condition is reported in step  608  and the process loops back to step  601 . Otherwise, the process directly loops back to step  601 . 
         [0080]    Returning now to  FIG. 5 , if the determination in step  501  is that a fault signal is not present, the process continues to step  502 . 
         [0081]    In step  502 , a determination is made whether the Master Control System is requesting service from smart power node  100 . The requested service can be a request to communicate with power node  100  to, for example, obtain the status of fault conditions, provide new conditions under which circuit interrupter  105  should be triggers, provide updated firmware for the operation of CPU  315 , etc. 
         [0082]    If yes, the Master Control System is serviced in step  503  and the process continues to step  506 . Otherwise, the process continues directly to step  506 . 
         [0083]    In step  506 , a determination is made whether a self-test of power node  100  should be performed. If yes, the self-test is performed in step  507  and the process continues to step  510 . 
         [0084]    In Step  510 , a determination is made whether electrical power usage data and other circuit parameters should be collected. If yes, power usage data and circuit parameters are determined and stored in steps  511 ,  515  and  516  by using sensor signals from voltage/current sensor  302  in  FIG. 3 . 
         [0085]    In step  519 , a decision is made whether the data should be reported to the Master Control System. If yes, the data is reported in step  520  and the process continues to step  601  in  FIG. 6 . Otherwise, the process continues directly to step  601 . 
         [0086]      FIG. 7  is a block diagram of one embodiment of a Master Control System (MCS)  700  in accordance with the present invention. As MCS  700  is able to communicate over the electrical wiring, it may operate from any location within an electrical power system. 
         [0087]    For example, MCS  700  may be fabricated in the physical size of a conventional circuit breaker and be plugged into an electrical power panel, such as across one of the power phase lines in a power panel. MCS  700  may also be fabricated as an external module with electric power blades that can be plugged into a conventional electric wall outlet or receptacle to establish an electrical connection to the electrical system. 
         [0088]    Moreover, MCS  700  may communicate with smart power nodes  100  using alternative communication path, such as via Bluetooth  714 , Lan/WiFi Interface  715 , Serial interface  716  and various other interfaces  717 . 
         [0089]    The operation of MCS  700  is controlled by CPU  711  which communicates with smart power nodes  100  over Power-Line Communications Interface  702  or one of the alternative communications paths. Status LED  705  and audio alarm  706  provide information on the status of MSC  700 , which are also controlled by CPU  711  via the CPU Signal And Data BUS. Voice circuit  707  may also be used to provide status reports in the form of a sensitized voice. 
         [0090]    Data Store  703  is provided for storing electrical fault, power consumption and circuit analysis information as might be reported by various smart power nodes. 
         [0091]    DHCP server  704  provides dynamic IP addresses to smart power nodes  100  that might require such an address as is known in the art. 
         [0092]    Also coupled to CPU  711  are RAM  708 , ROM  709  and Non Volatile Memory  710 . These elements operate in a similar manner as RAM  312 , ROM  314  and Non Volatile Memory  316  operate with respect to CPU  315  as described with respect to  FIG. 3 . 
         [0093]      FIG. 8  is a block diagram of a further embodiment of a smart power node  800  in accordance with the present invention. In this embodiment, Monitor/Controller  801  is used to individually control electric power to a plural of loads using circuit interrupters  805 A- 805   n.  The circuit interrupters are controlled by control trigger lines  802 A- 802   n.    
         [0094]    Smart power node  800  may be formed in a power strip which provides a plurality of outlet receptacles as such power strips are known in the art. 
         [0095]    Smart power nodes  100  and  800  may also be formed as an inline module that could be put into the wall (out of sight) or externally mounted and inserted into the electrical wiring between the outlet/device and the circuit breaker panel for existing outlets or other devices (such as outdoor pool pumps, spa pumps, etc.) 
         [0096]    In accordance with the present invention, smart power nodes  100  and  800  may also include one or more sensors for detecting the condition of the environment surrounding the power node as illustrated in  FIG. 9 . 
         [0097]    For example, power node  100  may include temperature, humidity and smoke sensors. The power node may also include sensors for measuring various gases such as natural gas, radon gas and CO2 gas. A camera may also be provided so that a visual record of the environment at any point in time can be created. The camera and a motion detector sensor may also be used to sound an alert when an authorized person enters the area. Similarly, a microphone can be used to detect unexpected sounds, such as someone trying to gain entry to the area. 
         [0098]    A sensor can also be provided to sense light conditions. Such a sensor may be used to trigger monitor/controller  110  to turn on a security light at dusk or turn one off at dawn by controlling circuit interrupter  105 . 
         [0099]    Other sensors, in addition to the ones shown in  FIG. 9 , may also be included in smart power nodes  100  and  800  as well. 
         [0100]    The sensor data is received by CPU  314  in  FIG. 3  and can be shared with other smart power nodes and/or forwarded to MCS  216 , Private Network Server  211  and/or Internet Server  212 , illustrated in  FIG. 2 , for retention and/or further analysis. 
         [0101]    The data from Voltage/Current Sensor  302  shown in  FIG. 3  may also be analyzed to determine circuit resistance between one power node and another node, or between one power node and another point on the power distribution system. Such functionality is important to determining circuit degradation over time, such as a nail breaking the insulation on a wire. 
         [0102]    After new construction, such functionality may be used to perform a safety check of the entire system. Moreover, a complete map of circuit resistances can be made and used to detect unauthorized modifications to the electrical network which could be used to prevent fire hazards or theft, etc. 
         [0103]    This functionality does not have to be packaged with an outlet or power strip, it may be fabricated in the form of an inline module that can be placed inside a wall out of sight. The module may also be externally mounted or inserted into the electrical wiring between an outlet or device and the circuit breaker panel for existing outlets or other devices (such as outdoor pool pumps, spa pumps, etc.) 
         [0104]    While the foregoing specification teaches the principles of the present invention, with examples provided for the purpose of illustration, it will be appreciated by one skilled in the art from reading this disclosure that various changes in form and detail can be made without departing from the true scope of the invention.