The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The method of reconstructing acceleration field was studied based on inversion of frequency response function matrix. In the method, the frequency response function (FRF) matrix was obtained. The vibration test was carried out and the test object was an underwater vehicle power-cabin. The results of theory study and test showed that the calculated precision by this method can satisfy the needs of...
This paper describes the experience from the world first installation of Smart High Voltage substation with IEC 61850 Process Bus where IEEE 1588 Time Synchronization and dynamic multicast filtering have been used. IEC 61850 is one the 30 standards identified by NIST as key elements for achieving interoperability in the Smart Grid. This paper describes the experience from a high voltage substation...
The IEEE 1588 standard is widely established and accepted for clock synchronization in Ethernet networks. High accuracy IEEE 1588 implementations require a well-coordinated hardware/software co-design. Processing of sophisticated control algorithms for the time speed of local clocks within synchronization slaves are particularly important. Hence, IEEE 1588 implementations should be tested with respect...
Some of the key infrastructure requirements for Smart Grid are the uninterrupted and reliable distribution of network data, information security and distribution of time information among network elements in order to accurately timestamp and correlate different network events. High Availability Seamless Ring (HSR) enabled networks can provide zero recovery time and PTPv2 enabled network can provide...
Using IEEE 1588 for highly accurate clock synchronization between nodes of a distributed system has become a widely accepted approach. IEEE 802.3/Ethernet is frequently utilized as communication layer to exchange the Precision Time Protocol (PTP) messages specified in the IEEE 1588 standard. 10/100/1000 MBit Ethernet communication is commonly used by now. In contrast, fiber optics based 10 GBit Ethernet...
With the increasing use of Ethernet for real-time control of distributed dynamic systems, and inexpensive processing power at the sensor and actuator nodes, there is a growing interest in the process control community to move towards “model based” distributed control. Prior work shows that the lack of precise time synchronization is a critical hindrance to reliable model generation or estimation in...
Widely used network measurement applications, such as tcpdump and Wireshark, use the same common libpcap packet capture library. Libpcap assigns a 10-6 second precision timestamp to all processed frames. Higher physical bandwidth implies shorter inter-arrival times between consecutive frames. Therefore timestamp precision must be proportional to the link speed. Latest version 1.0.x of libpcap provides...
This paper describes the experience from the world first installation of High Voltage substation with IEC 61850 Process Bus where IEEE 1588 Time Synchronization and dynamic multicast filtering have been used. The authors provide brief introduction to the concept of digital substation and process bus, then provide overview of IEEE 1588 standard for precise time synchronization and finally describe...
According to the requirement for a protection scheme based on synchronized phasor measurement in distribution networks with distributed generations, a RPR-based PPS distribution scheme was proposed. In this scheme, reserved control code group K28.6 in Ethernet physical coding layer is used as PPS positive edge transferred with preemptive priority in both ringlets of RPR. And a compensation algorithm...
This paper reviews real-time (RT) Ethernet and discusses special requirements for numerical control (NC). Then such a real-time Ethernet - EtherMAC (Ethernet for Manufacture Automation Control) is presented. EtherMAC uses master-slave communication structure. The master device supports standard Network Interface Card (NIC), and the slave device has a modified one - removing CSMA/CD (Carrier Sense...
In distributed environments, the coordination of distributed entities and events requires time synchronization. Precision time synchronization supports a variety of extensions of applications. The IEEE 1588 precision time protocol (PTP) provides a standard method to synchronize devices in a network with sub-microsecond precision. This paper includes the design and implementation of a PTP bridge to...
Data Synchronization is important in advanced application of Integrated Power System Power Management System. This issue compared the mostly time Synchronization protocols and proposed a data Synchronization collection method based IEEE1588. The theory of IEEE1588 protocol is introduced and the basic methods to control synchronization precision is analyzed. Then a synchronization measurement network...
Synchronized measurement technology (SMT) has the potential of becoming the backbone these Intelligent Electronic Devices (EIDs). The major advantages of using SMT are that all measurement signals are attached with a high-accuracy time stamp. This PTP-BASED system is one of these systems and comprise three main technologies: a PTP slave LM3S8962 microcontroller, a floating point DSP (TMS320C6713)...
This paper presents an IEEE 1588-2008 adapter that provides existing Gigabit Ethernet equipment with the functionalities required to clock synchronization on the order of sub-microsecond. To compensate the time error caused by the queuing delays in the Gigabit Ethernet equipment, the adapter measures the residence time and runs the peer delay mechanism for the equipment. Major functional blocks including...
It requires accurate synchronization among the MCU, servo controllers and sensors in CNC systems for time stamping of data and motion control. This paper presents the design and implementation of time synchronization for CNC systems which employ switched Ethernet as its communication module. The method adopts the clock of switches as the master clock instead of that of MCU which usual is. To obtain...
In various CNC systems the MCU, servo controllers and sensors all need to be accurately synchronized for time stamping of data and motion control. This paper presents a time synchronization method for CNC systems based on switched Ehternet in which message delay variation through switches must be minimized or compensated to obtain accurate time synchronization. The method uses the switch as the time...
This paper focuses on the synchronization between master clock and slave clock in the Distributed clock of EtherCAT. It supports very accurate synchronization function which let local slaves follow reference time under the degree of few nano second differences. However, there exists the propagation delay between reference clock and slave clock. To remove the delay, EtherCAT uses the static compensation...
A simple synchronizer is proposed to provide synchronization on asynchronous network with the modified time protocol based on packet transfer. The proposed synchronizer has enhanced performance for time accuracy and its simple structure is easily attached to legacy network elements such as Ethernet L2 switch.
White Rabbit (WR) is the project name for a ambiguous project that uses Ethernet as both, deterministic (synchronous) data transfer and timing network. The presented design aims for a general purpose, fieldbus like transmission system, which provides deterministic data and timing to approximately 1000 timing stations. The main advantage over conventional systems is the highly accurate timing (sub-nanosecond...
This paper preliminarily examines the applicability of Internet protocol (IP)-related communication technologies such as IP and MPLS (multi-protocol label switching) routers and L2 (layer-two or Ethernet) switches to existing teleprotection systems. The teleprotection systems concerned include microprocessor-based current differential teleprotection with data communications of instantaneous current...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.