BR9815716B1 - electronic metering system comprising a wide area network, a local area network and a means of access. - Google Patents

Description

Report of the Invention Patent for "ELECTRONIC MEASURING SYSTEM UNDERSTANDING A WIDE AREA NETWORK, A LOCAL NETWORK AND A MEANS OF ACCESS".

FIELD OF INVENTION

The present invention relates generally to electronic meters and automatic meter reading, and more particularly to TCP / IP-enabled electronic meters for two-way distance access via local and remote networks.

BACKGROUND OF THE INVENTION

The present invention relates to automatic meter reading (AMR) systems for use in automatic reading of electricity and other utility meters (e.g. water and gas meters). The invention is intended more particularly for use in, but not limited to, an electronic meter. Additional information on the electronic meter background can be found in US Patent No. 5,548,527 of August 20, 1996 entitled "Programmable Electrical Energy Meter Using Non-Volatile Memory" (assigned to ABB Power T&D Company Inc. ). Additional background in automatic meter reading systems can be found in U.S. Patent No. 5,553,094 of September 3, 1996, entitled "Radio Communication Network for Remote Data Generating Stations."

SUMMARY OF THE INVENTION

The present invention, as discussed in more detail below, involves the use of a TCP / IP protocol suite and a hypertext transfer protocol (HTTP) server. The terms "HTTP" and "TCP / IP" are well known in the art of networking and telecommunications. For example, TCP / IP refers to a well-known set of protocols for connecting devices across networks. The invention also involves the use of a "means of access". An access medium is a node in a network that connects two networks that are otherwise incompatible. Means of access may perform code and protocol conversion processes. A "protocol" is a set of rules or procedures regarding the format and timing of data transmissions between two devices. Protocols typically divide a file into blocks or packets of equal size. These are sent and the receiving device uses a mathematical procedure to determine if the block or packet was received accurately.

An electronic measurement system according to the present invention includes a remote network (WAN) operating in accordance with a TCP / IP protocol; a local area network (LAN) comprising a plurality of meters, each of which includes meter electronics for measuring a prescribed amount provided by a utility and memory for storing metered data and meter control parameters; a means of access operably coupled to the LAN and WAN; and an HTTP server operably coupled to the LAN and the access medium, whereby the WAN is provided with remote access to the measured data and meter control parameters.

Presently preferred embodiments of the invention include a CGI application coupled to the HTTP server for use in accessing the measured data. Alternatively, the inventive system may include a virtual machine attached to the HTTP server for use in accessing the data.

The prescribed amount is preferably electricity, water or gas.

The HTTP server and CGI application can be embedded in each meter or alternatively embedded in the access medium. Other features of the present invention are disclosed below.

BRIEF DESCRIPTION OF DRAWINGS

Figure 1 schematically depicts an AMR network including a remote network 10, access medium 20, local network 30, and meters 40 in accordance with the present invention.

Figure 2 schematically depicts one embodiment of the present invention in which an HTTP server and a common access medium interface are located at meter (s) 40.

Figure 3 schematically represents an embodiment of the present invention in which an HTTP server and a common access interface are located on access medium 20. Figure 4 illustrates how the common access interface could be replaced by a virtual machine Java is a Java applet.

Figure 5 depicts one embodiment of the invention in which one or more computers are giving access to the meters via a PPP server or interface.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention, in one embodiment, employs an electronic meter incorporating a TCP / IP protocol suite and an HTTP server for two-way access to meter data. In another embodiment of the invention, the TCP / IP protocol suite is incorporated into an access medium serving multiple meters connected by a power line or two-way wireless network. The access medium employed in a second embodiment of the present invention incorporates an HTTP server for accessing data from multiple meters and for data transmission to individual meters.

The basic architecture of the present invention is shown in Figure 1. As mentioned, embedding a server ΗΤΓΡ and a TCP / IP protocol stack within a meter 40 or a multi-meter access medium 20 over a local area network (LAN) 30 enables remote access to meter parameters on a continuous basis. As shown, a set of N meters 40 communicate via a non-TCP / IP LAN type 30. LAN 30 may be, for example, a CEBus network employing radio frequency communications power line. (the Electronic Consumer Bus (CEBus) protocol was adopted as a standard of the Electronic Industry Association (EIA IS-60), and defines a LAN that uses multiple media, including power lines, radio, twisted pair, coiled cable). - xial, and infrared signals). Also connected to LAN 30 is an access medium 20 that is also connected to a TCP / IP 10 (WAN) remote network. Other applications (not shown) are also connected to TCP / IP 10 WAN and may need to access individual meters or meter groups. These applications access individual meters by sending packet commands with attached TCP / IP destination addresses that are unique to each meter. In the first embodiment of the invention (Figure 2), access medium 20 receives packets from other applications on WAN 10. Access medium 20 includes a TCP / IP interface 22 and a LAN interface 28. LAN interface 28 includes software to transform the data packets into the required format for transmission on LAN 30. Access means 20 then transmits these reformatted packets over LAN 30 to meters 40. The steps involved in this transformation are:

1. The access medium examines the packet's TCP / IP address and determines if it is the address of a meter or meters within the set affixed to an access medium by its LAN. If not, the package is ignored.

2. If the packet is intended for one of the meters on the LAN of the access medium, the access medium examines the meter TCP / IP address affixed to the packet and determines whether it is an individual meter address or a broadcasting address.

3. If the packet is addressed to an individual meter, then the access medium encapsulates the packet into a larger packet that is addressed to the meter using its unique LAN address (which is different from its TCP / IP address).

4. If the packet is intended for broadcast to all meters, then the access medium encapsulates the packet into a larger packet addressed to the LAN special broadcasting address (which is different from the TCW broadcasting address).

5. If the packet is larger than the maximum allowable LAN packet size, then the access medium breaks the packet into smaller pieces. Each piece is labeled with the same LAN address as the original larger packet.

6. Each piece of the segmented packet is transmitted over the LAN for reception by one or more of the meters. The access medium is responsible for receiving acknowledgments of packet receptions from the meters, and for relaying packets if they are not received.

Each individual meter listens on the packet LAN. A meter reconstitutes the original WAN TCP / IP packet from one or more LAN packets, then executes the commands contained in the packet and sends the results back to the access medium. The steps involved in this process are:

1. The meter examines the packet's LAN address to see if it is intended for this meter or is it a broadcasting address. If the address is none of these, the meter ignores the packet.

2. If the packet is specifically addressed to the meter, a receive acknowledgment is sent back to the access medium. If an error is encountered in the packet, a negative acknowledgment is sent back to the access medium. For broadcast broadcasts, no acknowledgment is sent.

3. The received packet is coupled to any previously received pieces of the larger segmented packet. When all chunks of the segmented packet are received, the entire original TCP / IP packet is extracted and sent to the TCP / IP interface software on the meter.

4. The TCP / IP interface software examines the packet to see what service is being requested. In this case, assume that the package is intended to provide service by the HTTP server. (There may be other servers that operate on the meter to which TCP / IP messages could be sent.)

5. The HTTP server examines the data packet to see what operation is being requested. In this case, it assumes that the package contains a request that an application program be run on the meter to extract its current reading and send it back to the originator of the request. The HTTP server will launch this application through the Common Access Medium Interface (CGI).

6. The CGI application will scan the meter application software to find the current reading. The meter application directly accesses the meter electronics to acquire the required information. The reading is passed back to the CGI application that writes the reading in a message that uses HTML. The HTML message is sent back to the HTTP server.

7. The HTTP server encodes the HTML message as a TCP / IP package and sends it to the meter's TCP / IP interface.

8. The meter's TCP / IP interface sends the packet to the access medium using the same set of steps that the access medium used to send the original request to the meter.

9. Once the access medium receives the TCP / IP packet from the meter, it retransmits the packet over the WAN where the originating application for the command can receive it.

In the second embodiment of the invention (Figure 3), the access means takes over most of the tasks assigned to the meters in the first embodiment (Figure 2). The HTTP 24 server and CGI application 26 are moved to access medium 20, and the meters retain only their interface 42 for non-TCP / IP LAN. Processing of packets received from WAN-10 proceeds as follows:

1. The access medium examines the packet's TCP / IP address and determines if it is the address of a meter or meters within the set affixed to the access medium through its LAN. If not, the package is ignored.

2. The TCP / IP interface software examines the packet to see what service is being requested. In this case, it assumes that the packet is intended to provide service now contained by the HTTP server in the middle of access. (There may be other server applications running on the meter to which TCP / IP messages could be sent.)

3. The HTTP server examines the data packet to see what operation is being requested. In this case, it assumes that the package contains a request that an application program is run to acquire the current reading from an individual meter and send it back to the originator of the order. The HTTP server will launch this application via CGI (26).

4. The CGI 26 application now runs within the access medium. It has to determine the specified meter's LAN address and send a command packet to it through the LAN.

5. The command is received by the meter and causes the meter application to examine the electronics to find the current reading.

6. The meter reading is encapsulated within a LAN packet and is sent back to the access medium.

7. The CGI application receives the meter LAN packet and extracts the meter reading. The read is written in an HTML message and is sent back to the HTTP server.

8. The HTTP server encodes the HTML message as a TCP / IP packet and sends it to the access medium's TCP / IP interface 22.

9. The TCP / IP interface of access medium 22 sends the packet through WAN 10 where the originating application for the command can receive it.

Both described implementations of the present invention have been described using CGI applications 46, 26 to manipulate the details of having current read access to a meter. As shown in Figure 4, the CGI application could be replaced by a Java (VM) 26 'virtual machine running a Java 26 "application that performs the same operations as the CGI application.

Additionally, both implementations were described using an example where the current reading of an individual meter is requested by a WAN-connected application. A WAN application can also write data to a meter or meters that use similar procedures. Data could modify parameters that affect meter or meter operations. An example would be rate updates.

Any implementation, using TCP / IP and HTTP servers, supports reading meters or setting their parameters using browsers such as Netscape ™ or Explorer ™. Utility companies and homeowners could perform meter reading on demand via their browsers. An individual meter or group of meters could be accessed as if the meter (s) were a network location and their current readings or other data could be displayed in the browser. The meters could send forms to the browser, which the user could fill in to change parameters in the meters. Both meter reading and updating would be protected by coding and passwords.

As shown in Figure 5, a browser could gain access to the meters over a telephone line to a Point-to-Point Protocol (PPP) 60 server attached to WAN 10 or directly attached to an access medium 20. The PPP server interfaces with modems (not shown) to provide a TCP / IP connection to a browser at the other end of the line. The PPP server sends phone line packets over the WAN where they are received by the appropriate access medium. In the case of a telephone line connection directly to an access medium, PPP software includes an interface 21 to connect directly to the WAN TCP / IP interface 22 so that packets received by the telephone line are handled in the same way as they are. packets received over WAN 10.

The browser can be replaced by an intelligent application program that accesses the HTTP server for automated meter reading and parameter setting on a programmed and repetitive basis. The application uses meter readings to create or update records in a database. This application could be a Java application that can interact with HTTP servers and databases that support HTTP protocols.

In summary, the present invention includes the following novel aspects: (1) HTTP server built into a meter for on-demand access to meter data and for setting meter parameters at a distance; (2) HTTP server built into a multi-meter access medium to read and set parameters on individual meters on a LAN; (3) Using CGI for remote access to meter data and meter parameter sets using HTML forms in HTTP browsers; (4) remote reading and remote setting of multiple meter parameters using TCP / IP protocol suite; (5) Set of TCP / IP protocol programs implemented on designated nodes on a CEBus LAN including CEBus routers and browsers with remote access via TCP / IP to the bridged router / router and thus individual mediators. in a LAN; (6) SLIP-PPP-enabled access medium for remote TCP / IP access via a serial interface (telephone line, or ISDN, for example) for single or multiple meter parameters (fix and read).

The foregoing detailed description of preferred embodiments of the invention does not mean to limit the scope of protection of the following claims. Those skilled in the art of electronic measurement will recognize that many modifications may be made to the presently preferred and described embodiments.

Claims (17)

1. Electronic measuring system, comprising: a wide area network, WAN; a local area network (LAN) comprising a plurality of meters (40) each of which includes meter electronics for measuring a prescribed quantity supplied by a plant and memory for storing meter data and control parameters; and an access means (20) operably coupled to said LAN and said WAN; characterized in that the electronic metering system comprises an HTTP server (24) operably coupled to said LAN and said access means (20), said HTTP server (24) being adapted to access said data. measured, whereby said WAN is provided with remote access to said measured data and control parameters of said meters (40); and where the wide area network, WAN, operates according to a TCP / IP protocol. System according to claim 1, characterized in that it further comprises a common access medium interface application, CGI, (26, 46) coupled to said HTTP server (24) for use in accessing said interfaces. measured data. System according to claim 1, characterized in that it further comprises a virtual machine coupled to said HTTP server (24) for use in accessing said data. System according to claim 1, characterized in that said prescribed quantity is electricity. System according to claim 1, characterized in that said prescribed quantity is gas. System according to claim 1, characterized in that said prescribed quantity is water. System according to claim 2, characterized in that said HTTP server (24) and CGI application (46) are embedded in each of said meters (40). System according to claim 1, characterized in that said HTTP server (24) and CGI application (26) are embedded in said access means (20). System according to claim 1, characterized in that each of said meters (40) further comprises a LAN interface (42). System according to claim 1, characterized in that said access means (20) further comprises a LAN interface (28). System according to claim 7, characterized in that each of said meters (40) further comprises a TCP / IP interface (43). System according to claim 1, characterized in that said access means (20) comprises a TCP / IP interface (22). System according to claim 1, characterized in that it further comprises a common access means interface application, CGI1 coupled to said HTTP server (44) for use in accessing said measured data; wherein said HTTP server (44) and CGI application (46) are embedded in each of said meters (40); wherein said access means (20) and each of said meters (40) comprise a LAN interface (42) and a TCP / IP interface (43); and wherein said prescribed amount is a member of a group consisting of electricity, water and gas. System according to claim 1, characterized in that it further comprises a common access means interface application, CGI, coupled to said HTTP server for use in accessing said measured data; wherein said HTTP server (24) and CGI application (26) are embedded in said access means (20); wherein each of said meters (40) and said access means (20) comprise a LAN interface (28, 42); wherein said access means (20) further comprises a TCP / IP interface (22); and wherein said prescribed amount is a member of a group consisting of electricity, gas and water. System according to claim 1, characterized in that said LAN is a CEBus LAN. System according to claim 13, characterized in that said LAN is a CEBus LAN. System according to claim 14, characterized in that said LAN is a CEBus LAN.