GVR Auto Recloser...

For Pole Mounting and Substation Application






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FIT AND FORGET RECLOSER: From a new generation of intelligent switchgear, the GVR brings the reliability of modern materials and technology to overhead distribution networks, achieving a lifetime of maintenance free operation.

With a Choice of Protection

Polarr
The standard Polarr relay offers full auto-reclose protection and control functionality. Its long life lithium batteries eliminate the need for an auxiliary supply.

Panacea
Alternatively, the Panacea offers the highest levels of control and protection for improved distribution network performance, from directional auto-reclosing for closed loop schemes to full remote control utilising the DNP3.0 protocol.

  1. The Whipp & Bourne patented, single coil magnetic actuator mechanism which allows the GVR to operate independently of the MV supply and to be tested in an ordinary workshop.
  2. Environmentally friendly vacuum interruption produces no by-products.
  3. The lightweight aluminium tank makes the GVR easier to transport and install.
  4. The EPDM or silicone rubber bushings are resistant to damage from vandalism or mishandling.
  5. By extensive use of insulated mouldings, in particular the bushings, the total number of parts has been reduced by a factor of x20 and the number of moving parts by x50.
  6. No scheduled maintenance for 30 years*

Environmental Design
The award-winning* GVR gas-filled vacuum recloser combines the high reliability of vacuum interruption with the controlled environment and high dielectric strength of SF6, in a compact, maintenance-free unit. Since SF6 is only used as insulation, there is no health hazard from toxic by-products of arcing. Electrical life is well in excess of ANSI requirements.
The patented, single coil magnetic actuator provides consistent performance and a dramatic reduction in the number of moving parts. Materials and finishes have been carefully chosen for reliability - from EPDM bushings, tested for tracking and erosion to IEC 61109, in salt, fog and other environments, to the neodymium iron boron permanent magnets used in the mechanism.


Application
The GVR can be pole mounted or substation mounted and can operate as a stand alone recloser without the need for an additional auxiliary supply, or it can be integrated into the most advanced distribution automation schemes.
By using the advanced control and protection functions of the Panacea, the GVR can also be used in applications where reclosers have not traditionally been used such as closed rings and underfrequency load shedding schemes.

ATTENTION TO ENGINEERING DETAIL

Main Features

  1. Single piece, aluminium or copper-cored EPDM
    or silicone rubber bushings, with grooves to take optional wildlife guards/MV boots.
  2. Current transformers are mounted within the tank's controlled environment, while optional capacitive voltage dividers provide voltage signals for use by the Panacea or an RTU.
  3. Aluminium housing with lightweight, moulded baseplate, secured by stainless steel bolts and incorporating rubber 'O' ring seals.
  4. Pressure-relief disc, to comply with IEC 60298 Appendix AA, offers the highest levels of safety.
  5. Mechanical ON/OFF position indication visible through clear viewing window from ground level.
  6. Hook stick-operated manual trip and lockout control.
  7. A single moulding supports the three phase vacuum interrupter assembly, magnetic actuator mechanism and one-piece drive beam.
  8. The patented, single coil magnetic actuator is based on a solenoid plunger, held in the tripped or closed position by a permanent magnet.

Patented, Single Coil Magnetic Actuator
The actuator coil is energised in one direction to
'power close' the GVR and in the opposite direction to open it by de-latching the holding force. This is a unique feature of the single coil actuator design used in the GVR and ensures reliable tripping operation under all battery conditions and even for manual trip.


Closing
The bi-stable design ensures that the plunger is held back in the open position (1) until the solenoid current rises above the level required to guarantee closure. Once the holding force is overcome (2), the circuit breaker closes positively (3), due to the stored energy in the solenoid and permanent magnets.


Tripping
The solenoid is energised in the reverse direction (4)
to overcome the magnetic hold-on force and de-latch the actuator. Opening is then completed by the energy stored during the closing stroke in the contact pressure and opening springs and is completely independent of the power supply during electrical opening, and of the operator during manual opening. The energy required to trip is approximately 1/30th of that required to close.

CONTROL AND PROTECTION

Principle of Operation
The Polarr is the standard relay package for the GVR. It measures the 3 phase and residual currents using CTs located in the GVR, and performs auto-reclosing over current, earth fault and sensitive earth fault protection. The low power, microprocessor architecture of the Polarr is unique to the power industry. Its design has been perfected over several years and offers the user significant benefits through the elimination of the need for any external power supply. In addition to this, the Polarr offers several advanced auto-reclosing functions in a comprehensive but cost effective package.

Weather Protection
The Polarr relay and control batteries are housed in
a control box located on the pole at ground height underneath the GVR. Connection to the GVR is via an umbilical cable and weather proof plug and socket that is used to carry the CT currents and the GVR control signals. The IP56 sealed control box is made from stainless steel, with an outer double skinned sun shield of polyester-coated galvatite. It protects against the harshest environment and maintains an even internal temperature keeping the relay condensation-free.

Control Batteries
High energy density lithium battery technology makes the GVR with Polarr ideal for applications where an auxiliary power supply is not available. Alternatively, where an auxiliary supply is already available, or when one is required to power an additional RTU and communications equipment, rechargeable lead acid batteries can be supplied
as an option.

Programming Protection Settings
Protection settings can be programmed via the dot matrix display and keypad or downloaded though the serial port from a notebook computer using libraries of settings created in Windows based software.

Data Logging
Historical, diagnostic and load current data can be accessed through the local display or the serial port. The Polarr history is held in non-volatile memory, and includes the time and date of the last 20 sequences together with the number of trips in the sequence and fault magnitude of each of the elements.

Minimum Trip Currents
The multi-ratio CTs located in the GVR and a wide range of programmable minimum trip settings ensure that the GVR and Polarr can be used at any point in the network, from substation through to the feeder ends with the earth fault currents as low as one ampere.

Short Cut Keys
In addition to large, clear control keys, LED indication and a menu-driven display for entering settings and viewing historic data, the front panel also incorporates three push-buttons for instant access
to load current, fault target and battery condition information.

Sequence Co-ordination
The Polarr's advance sequence co-ordination logic and fast response times of the relay allow co-ordinating delays as low as 60mS to ensure that
only the recloser closest to the fault operates.

Local Control
Push-buttons are provided for the standard auto-recloser functions, while separate keys and LED indication are used for the circuit breaker control.

Remote Control
All of these functions are also available through a parallel SCADA port on the back of the relay, accessible through a gland plate in the control box. Voltage free contacts and opto-isolated inputs offer a standard interface to a third party RTU of the customer's choice. Alternatively, an enlarged control box to house an RTU and rechargeable battery pack can be provided. More advanced remote control functionality is provided by the Panacea.

GVR Control and Diagnostics
Operation of the GVR actuator is through energy stored in long life capacitors.

Uninterruptable Power Supply
The Panacea Uninterruptable Power Supply (UPS) is suitable for 120 vac. It includes a long life 24 volt lead acid battery for standby use, with temperature controlled charging and a battery test facility.
The UPS module monitors the auxiliary supply status, operating characteristics and battery temperature to ensure continuity of supply under all operating conditions.

The Power System Variables
The line and residual currents are measured using CT's located inside the GVR. The voltage on both sides of the GVR and the residual voltage are taken from internal capacitive dividers or external VT's. The output of these transducers is produced in the Protection and Measurement module using a combination of high speed analogue circuitry and digital signal processing.

Protection
In addition to directional over current, earth fault and sensitive earth fault auto-reclose protection, advanced directional earth fault algorithms allow the Panacea to make an automatic selection of the best earth fault directional element for the system conditions. Other protection features such as load encroachment logic and underfrequency load shedding increase the functionality of the GVR to levels previously only available in complex substation schemes.

Metering and Load Profile
The power system variables including the volts, amps, watts and vars, can be viewed in real time on the Panacea front panel or remotely through the serial port. It is also possible to average the current and voltage measurements over 5, 15, 30 or 60 minute periods to produce a load profile. This can be stored in memory and later downloaded through the local or remote serial ports.

Event Reporting
The Panacea can be set up to record various events such as loss of auxiliary power or a protection event. Up to 512 events can be stored in non-volatile memory, each one date and time-stamped. This is supported by a separate oscillogram report showing up to thirty 15-cycle or fifteen 30-cycle reports.

Local Control
The Panacea local control panel offers the same basic functionality as the Polarr. Local LED indication has been increased to offer even greater operational and system status information.

Remote Control
The Panacea controls, status indication, settings and history are available remotely through one of 2 serial ports on the back of the relay. It is possible to connect directly to a radio or modem and to communicate with a SCADA system using the DNP3.0 protocol (other protocols available on request). Space is provided in the control box to mount a suitable radio or modem and the UPS provides a 12 volt 0.5 amp fused supply.

Capacitive Voltage Sensing (CVTs)
Located inside the GVR, these CVTs are a low cost method of measuring source and load voltage. They can be used with the Panacea for direct voltage measurement.

The Loop Scheme Control System (LSCS)
The Loop Scheme Control System (LSCS) is used to automatically restrict permanent faults to a smaller section of a distribution system, whilst maintaining supply to the un-faulted sections. For a typical five recloser based Loop Scheme, a permanent fault anywhere on either feeder should never result in the loss of more than one third of the load on the affected feeder. Using the power and flexibility of SELogic a customer specific logic scheme can be developed.

The SEL-351R Recloser Control
For recloser users whose policy it is to standardise on the Schweitzer 351-R Protection and Control rather than the Panacea, then the option is available. The SEL-351R Recloser Control combines traditional recloser control functions with technologically advanced SEL relaying features. In the USA, Schweitzer Engineering Laboratories provide complete technical support for the entire control cabinet.

Operating Sequence
Up to 4 trips to lockout are available for over current, earth fault and sensitive earth fault sequences. The time between GVR clearing the fault and reclosing is known as the dead time and is selectable for each trip. If the fault is temporary, the protection will begin to reclaim after reclosing. If the fault is permanent, the GVR will lockout after the last trip. A Cold Load Pickup feature avoids spurious tripping when manually closing onto de-energised loads.

Time Current Characteristics
Time current characteristics are programmable for every trip in the sequence. There is a choice of time dependant curves of definite time. The curves can be modified using time multipliers, additional delays and minimum response times. Instantaneous protection offers the fastest fault clearing times and can be used with additional delays for sequence co-ordination.

Minimum Trip Settings
The combination of multi-tapped protection CTs and the range of trip settings within Polarr and Panacea relays ensure suitable operation at any point in a network.

Directional Control
Phase and ground directional elements are standard features of the Panacea. Direction and polarization settings are available for the control of the phase elements, earth fault elements and the negative sequence elements.
Polarization quantities include positive sequence voltage, negative sequence voltage and zero sequence
voltage.