Claims:WE CLAIM:
1. A system (100) for assisting operation of a distribution switchgear (102), said distribution switchgear (102) comprising a pressure gauge and at least two isolator legs (104), said pressure gauge configured to monitor pressure of an isolating gas within said distribution switchgear (102), each of said isolator legs (104) having a disconnect switch (110), an earth switch (118), and a Voltage Presence Indicator (VPI) (112), said VPI (112) being configured to indicate presence of voltage across said associated isolator leg (104), said system (100) comprising:
i. a first limit switch associated with each of said earth switches (118), said first limit switch configured to operate upon detecting movement of an access channel of said associated earth switch (118);
ii. a control unit (114) associated with each of said isolator legs (104), said control unit (114) configured to cooperate with said disconnect switch (110), said earth switch (118), said VPI (112), said pressure gauge, and said first limit switch to receive signals corresponding to the status of said disconnect and earth switches (110, 118), state of said VPI (112), and pressure within said distribution switchgear (102), upon the operation of said associated first limit switch, said control unit (114) further configured to analyze said received disconnect-switch status signal, earth-switch status signal, VPI-state signal, and pressure signal to output at least one electrical signal based on a pre-determined set of output generation rules; and
iii. a speaker (116) configured to cooperate with said control unit (114) to receive said electrical signal, and further configured to generate a sound output for assisting an operator working on said distribution switchgear (102) based on said received electrical signal.
2. The system (100) as claimed in claim 1, wherein said control unit (114) comprises:
i. a memory (202) configured to store said pre-determined set of output generation rules;
ii. a first input port (204) connected to a contact of said disconnect switch (110) to receive said disconnect-switch status signal;
iii. a second input port (206) connected to a contact of said earth switch (118) to receive said earth-switch status signal;
iv. a third input port (208) connected to the VPI (112) of said isolator leg (104) to receive said VPI state signal;
v. a fourth input port (214) connected a contact of said pressure gauge to receive said pressure signal;
vi. an analyzing module (210) configured to cooperate with said first, second, third, and fourth input ports (204, 206, 208, 214) to receive said disconnect-switch status signal, said earth-switch status signal, said VPI state signal, and said pressure signal upon the operation of said first limit switch, said analyzing module (210) further configured to cooperate with said memory (202) to analyze said received signals and generate said electrical signal based on said pre-determined set of output generation rules; and
vii. an output port (212) connected to said speaker (116), said output port (212) configured to receive said electrical signal from said analyzing module (210), and further configured to output said electrical signal to said speaker (116).
3. The system (100) as claimed in claim 1, wherein said control unit (114) is configured to detect an unsafe operating pressure condition based on said received pressure signal and said pre-determined set of output generation rules, and is further configured to generate and provide a first electrical signal to said speaker (116), for facilitating generation of a sound output to notify the operator about the unsafe operating pressure condition.
4. The system (100) as claimed in claim 1, wherein said control unit (114) is configured to detect a safe operating pressure condition based on said received pressure signal and said pre-determined set of output generation rules, and is further configured to generate and provide a second electrical signal to said speaker (116) for facilitating generation of a sound output to notify the operator about safe operating pressure condition.
5. The system (100) as claimed in claim 1, wherein said system (100) is implemented as a stand-alone unit.
6. The system (100) as claimed in claim 1, wherein said system (100) is integrated with said distribution switchgear (102).
7. The system (100) as claimed in claim 1, wherein said control unit (114) is configured to detect an unsafe condition for operating said earth switch (118) based on said received earth-switch status signal, VPI state signal, and said pre-determined set of output generation rules, and is further configured to:
i. generate and provide a third electrical signal to said speaker (116) for facilitating generation of a sound output to notify the operator about said detected unsafe operating condition; and
ii. generate a trigger signal to activate an electrically operated mechanical switch for restricting the operation of said earth switch (118).
8. The system (100) as claimed in claim 7, wherein said control unit (114) is configured to de-activate said electrically operated mechanical switch when said access channel associated with said earth switch (118) is released.
9. The system (100) as claimed in claim 7, wherein said control unit (114) is configured to generate a fourth electrical signal if said unsafe operating condition is not detected, and is further configured to provide said generated fourth electrical signal to said speaker (116) for facilitating generation of a sound output to notify the operator about safe operating condition.
10. The system (100) as claimed in claim 1, wherein said distribution switchgear (102) is a Ring Main Unit (RMU) switchgear.
11. The system (100) as claimed in claim 1, which includes a second limit switch associated with each of said disconnect switches (110), said second limit switch configured to operate upon detecting movement of an access channel of said associated disconnect switch (100).
12. The system (100) as claimed in claim 11, wherein said control unit (114) is configured to cooperate with said second limit switch to generate and provide a fifth electrical signal to said speaker (116) for facilitating generation of a sound output to notify the operator about the disconnect switch (110) being operated.
13. A method for assisting operation of a distribution switchgear (102), said distribution switchgear (102) comprising a pressure gauge and at least two isolator legs (104), said pressure gauge configured to monitor pressure of an isolating gas within said distribution switchgear (102), each of said isolator legs (104) having a disconnect switch (110), an earth switch (118), and a Voltage Presence Indicator (VPI) (112), said VPI (112) being configured to indicate presence of voltage across said associated isolator leg (104), said method (300) comprising:
i. detecting, by a control unit (114), pressure of an isolating gas within said distribution switchgear (102), by receiving a state of a contact of said pressure gauge;
ii. generating, by said control unit (114), a first electrical signal based on a pre-determined set of output generation rules, if said detected pressure is below a safe operating pressure value;
iii. receiving, by a speaker (116), said first electrical signal from said control unit (114);
iv. generating, by said speaker (116), a sound output based on said received first electrical signal to notify an operator about unsafe operating pressure;
v. detecting, by a first limit switch, movement of a channel associated with said earth switch (118);
vi. receiving, by said control unit (114), signals corresponding to a status of said earth switch (118), and state of said VPI (112) associated with said isolator leg (104) upon the operation of said first limit switch;
vii. detecting, by said control unit (114), an unsafe operating condition based on said received earth-switch status signal, VPI state signal, and the pre-determined set of output generation rules;
viii. if an unsafe condition is detected-
• generating, by said control unit (114), a third electrical signal;
• receiving, by said speaker (116), said third electrical signal from said control unit (114);
• generating, by said speaker (116), a sound output based on said received third electrical signal to notify the operator about said detected unsafe operating condition; and
• generating, by said control unit (114), a trigger signal to activate an electrically operated mechanical switch for restricting the operation of said earth switch (118) upon detecting said unsafe operating condition; and
ix. if an unsafe condition is not detected-
• generating, by said control unit (114), a fourth electrical signal;
• receiving, by said speaker (116), said fourth electrical signal from said control unit (114); and
• generating, by said speaker (116), a sound output based on said received fourth electrical signal to notify the operator about safe operating condition.
14. The method as claimed in claim 13, which includes:
i. generating, by said control unit (114), a second electrical signal based on said pre-determined set of output generation rules, if said detected pressure is greater than or equal to said safe operating pressure value;
ii. receiving, by said speaker (116), said second electrical signal from said control unit (114); and
iii. generating, by said speaker (116), a sound output based on said received second electrical signal to notify the operator about safe operating pressure.
, Description:FIELD
The present disclosure relates to the field of electrical power distribution systems. More particularly, the present disclosure relates to a system for assisting operation of a distribution switchgear and a method thereof.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
An electric power distribution system supplies power to various consumer premises from a substation by means of feeders. The electric power distribution system is classified into radial distribution system, parallel feeders distribution system, ring main distribution system, and interconnected distribution system according to its feeder connection schemes or topologies. Each of these systems comprises a distribution switchgear including circuit breakers, isolators/disconnectors, and a variety of protection devices. The distribution switchgears are used to facilitate control, protection and isolation of the distribution feeders.
Most of the existing power distribution systems are ring main and interconnected distribution systems. These systems are generally used for medium to high voltage power distribution. The feeders, in these systems, form a loop which starts from the substation bus-bars, runs through the load area feeding distribution transformers and returns to the substation bus-bars. Each distribution transformer is fed with two feeders but in different paths as in radial system. Thus, if one feeder is under fault or maintenance, the transformer will still be energized by other feeders connected to it. This leads to an improvement in system reliability.
The distribution switchgear in the power distribution system is used both for isolating a feeder and for implementing outages to clear faults downstream. Accordingly, an operation engineer works on a distribution switchgear under two conditions – (i) when a fault occurs in the network and (ii) for implementing outages under normal conditions. In both the conditions, there is a possibility of human error to creep in, leading to unintended operation of the isolators which can cause damage to the equipment and the operator.
Under normal conditions, the line isolators/load break switches and circuit breakers in a distribution switchgear are closed and the ground isolator/earth switch is open. During the maintenance period, the circuit breakers and line isolators/load break switches are opened, and the ground isolator/earth switch is closed. Accordingly, the sequence of breaking the circuit under fault conditions or for maintenance purposes is – open the line isolator, check back charging status (on Voltage Presence Indicator System), and close the ground isolator.
In ring main, parallel and interconnected distribution systems, there is always a possibility of back feeding or back charging because the distribution system is in the form of a loop or ring. If backfeeding occurs from another RMU side, one end of the earth switch and the cable will be live. If backfeeding is not detected by the operator, the operator may operate the earth switch. This would lead to direct grounding of the live cable i.e. dead short circuit three phases to earth, which can lead to heavy discharge between the contacts of these isolators/switches until the feeder circuit breaker trips on this fault, thereby endangering the operator’s life, which is not desired.
Therefore, there is a need for a voice assistant system to prevent maloperation of the isolators at the distribution switchgear.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
It is an object of the present disclosure to provide a system for assisting operation of a distribution switchgear.
Another object of the present disclosure is to provide a voice assistant system that facilitates easy operation of the distribution switchgear.
Still another object of the present disclosure is to provide a system for assisting operation of a distribution switchgear that notifies an operator about the disconnect switch being operated.
Yet another object of the present disclosure is to provide a system for assisting operation of a distribution switchgear that alerts the operator about an unsafe operating condition.
Still another object of the present disclosure is to provide a system for assisting operation of a distribution switchgear that restricts the operation of the earth switch upon detecting an unsafe operating condition.
Yet another object of the present disclosure is to provide a system for assisting operation of a distribution switchgear that alerts the operator in time to prevent wrong operation of the switchgear.
Still another object of the present disclosure is to provide a system for assisting operation of a distribution switchgear that is compatible with existing Ring Main Units (RMUs) and other distribution switchgears.
Yet another object of the present disclosure is to provide a system for assisting operation of a distribution switchgear that is backward compatible.
Still another object of the present disclosure is to provide a system for assisting operation of a distribution switchgear that ensures operator and equipment safety.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure envisages a voice assistant system for a distribution switchgear. The distribution switchgear is a Ring Main Unit (RMU) switchgear and comprises a pressure gauge and at least two isolator legs. The pressure gauge is configured to monitor pressure of an isolating gas within the distribution switchgear. Each isolator leg includes a disconnect switch, an earth switch, and a Voltage Presence Indicator (VPI). The VPI is configured to indicate presence of voltage across the associated isolator leg. The voice assistant system comprises a first limit switch, a control unit and a speaker. The first limit switch is associated with each of the earth switches. The first limit switch is configured to operate upon detecting movement of an access channel of the associated earth switch. The control unit is associated with each of the isolator legs. The control unit is configured to cooperate with the disconnect switch, the earth switch, the VPI, pressure gauge, and the first limit switch to receive signals corresponding to the status of the disconnect and earth switches, state of the VPI, and pressure within said distribution switchgear, upon the operation of the associated first limit switch. The control unit is further configured to analyze the received disconnect-switch status signal, earth-switch status signal, VPI-state signal, and pressure signal to output at least one electrical signal based on a pre-determined set of output generation rules. The speaker is configured to cooperate with the control unit to receive the electrical signal, and is further configured to generate a sound output for assisting an operator working on the distribution switchgear based on the received electrical signal.
In an embodiment, the control unit comprises a memory, a first input port, a second input port, a third input port, a fourth input port, an analyzing module, and an output port. The memory is configured to store the pre-determined set of output generation rules. The first input port is connected to a contact of the disconnect switch to receive the disconnect-switch status signal. The second input port is connected to a contact of the earth switch to receive the earth-switch status signal. The third input port is connected to the VPI of the isolator leg to receive the VPI state signal. The fourth input port is connected a contact of the pressure gauge to receive the pressure signal. The analyzing module is configured to cooperate with the first, second, third input, and fourth input ports to receive the disconnect-switch status signal, the earth-switch status signal, the VPI state signal, and the pressure signal upon the operation of the first limit switch. The analyzing module is further configured to cooperate with the memory to analyze the received signals and generate the electrical signal based on the pre-determined set of output generation rules. The output port is connected to the speaker. The output port is configured to receive the electrical signal from the analyzing module, and is further configured to output the electrical signal to the speaker.
Advantageously, the control unit is configured to detect an unsafe operating pressure condition based on the received pressure signal and the pre-determined set of output generation rules. The control unit is further configured to generate and provide a first electrical signal to the speaker for facilitating generation of a sound output to notify the operator about unsafe operating pressure; or
In an embodiment, the control unit is configured to detect a safe operating pressure condition based on the received pressure signal and the pre-determined set of output generation rules, and is further configured to generate and provide a second electrical signal to the speaker for facilitating generation of a sound output to notify the operator about safe operating pressure.
In an embodiment, the control unit is configured to detect an unsafe operating condition for operating the earth switch based on the received, earth-switch status signal, VPI state signal, and the pre-determined set of output generation rules, and is further configured to:
• generate and provide a third electrical signal to the speaker for facilitating generation of a sound output to notify the operator about the detected unsafe operating condition; and
• generate a trigger signal to activate an electrically operated mechanical switch for restricting the operation of the earth switch.
In an embodiment, the control unit is configured to de-activate the electrically operated mechanical switch when the access channel associated with the earth switch is released.
In an embodiment, the control unit is configured to generate a fourth electrical signal if the unsafe operating condition is not detected, and is further configured to provide the generated fourth electrical signal to the speaker for facilitating generation of a sound output to notify the operator about safe operating condition.
In an embodiment, the system includes a second limit switch associated with each of the disconnect switches. The second limit switch is configured to operate upon detecting movement of an access channel of the associated disconnect switch. The control unit is configured to cooperate with the second limit switch to generate and provide a fifth electrical signal to the speaker for facilitating generation of a sound output to notify the operator about the disconnect switch being operated.
In an embodiment, the system is implemented as a stand-alone unit. In another embodiment, the system is integrated with the distribution switchgear.
The present disclosure also envisages a method for assisting operation of a distribution switchgear.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
A system for assisting operation of a distribution switchgear and a method thereof of the present disclosure will now be described with the help of the accompanying drawing, in which:
Figure 1 illustrates a line diagram of a system for assisting operation of a distribution switchgear;
Figure 2 illustrates a block diagram of a control unit of the system of Figure 1; and
Figures 3A and 3B illustrate a flow diagram depicting steps involved in a method for assisting operation of a distribution switchgear.
LIST OF REFERENCE NUMERALS
100 – System
102 – Distribution switchgear
104 – Isolator Legs
106 – Breaker Leg
108 – Circuit breaker
110 – Disconnect switches
112 – Voltage Presence Indicators (VPIS)
114 – Control units
116 – Speakers
118 – Earth switches
202 – Memory
204 – First input port
206 – Second input port
208 – Third input port
210 – Analyzing module
212 – Output port
214 – Fourth input port
DETAILED DESCRIPTION
Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details, are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, integers, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, integers, operations, elements, components, and/or groups thereof.
When an element is referred to as being "mounted on," or "connected to," another element, it may be directly on or connected to the other element.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element from another element. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
A system for assisting operation of a distribution switchgear (hereinafter referred as “system 100”) and a method thereof (hereinafter referred as “method 300”), of the present disclosure, is now being described with reference to Figure 1 through Figure 3B.
The distribution switchgear 102 is a totally sealed, gas-insulated, compact switchgear unit. The distribution switchgear 102 comprises at least two isolator legs 104. Each of the isolator legs 104 includes a disconnect switch 110 and an earth switch 118. The distribution switchgear 102 may also include at least one breaker leg 106. The breaker leg 106 includes a circuit breaker 108, a line isolator/disconnect switch 110, and an earth switch 118. The disconnect switches 110 and the earth switches 118 include a plurality of contacts. The distribution switchgear 102 also comprises a pressure gauge. The pressure gauge is configured to monitor pressure of an isolating gas within the distribution switchgear 102. In an embodiment, the distribution switchgear 102 is a Ring Main Unit (RMU) distribution switchgear.
Referring to Figure 1, the system 100 of the present disclosure comprises a first limit switch, a control unit 114, and a speaker 116. The first limit switch is associated with each of the earth switches 118. The first limit switch is configured to operate upon detecting movement of an access channel of the associated earth switch 118. The distribution switchgear 102 includes a plurality of Voltage Presence Indicators (VPIS). A VPI 112 is connected in each of the isolator and breaker legs (104, 106). The VPIS 112 are configured to indicate presence of voltage across the isolator legs 104 and the breaker legs 106. The control unit 114 is associated with each of the isolator legs 104. The control unit 114 is configured to cooperate with the disconnect switch 110, the earth switch 118, the VPI 112, the pressure gauge, and the first limit switch to receive signals corresponding to the status of the disconnect and earth switches (110, 118), state of the VPI 112, and pressure within said distribution switchgear 102, upon the operation of the associated first limit switch. The control unit 114 is further configured to analyze the received disconnect-switch status signal, earth-switch status signal, VPI-state signal, and pressure signal to output at least one electrical signal based on a pre-determined set of output generation rules. In an embodiment, the operation of the first limit switch triggers the control unit 114 to check the status of the disconnect and earth switches (110, 118) and state of the VPI 112. The speaker 116 is configured to cooperate with the control unit 114 to receive the electrical signal, and is further configured to generate a sound output for assisting an operator working on the distribution switchgear 102 based on the received electrical signal.
Referring to an embodiment of Figure 2, the control unit 114 comprises a memory 202, a first input port 204, a second input port 206, a third input port 208, a fourth input port 214, an analyzing module 210, and an output port 212. The memory 202 is configured to store the pre-determined set of output generation rules. The first input port 204 is connected to a contact of the disconnect switch 110 to receive the disconnect-switch status signal. The second input port 206 is connected to a contact of the earth switch 118 to receive the earth-switch status signal. The third input port 208 is connected to the VPI 112 of the isolator leg 104 to receive the isolator-VPI state signal. The fourth input port 214 is connected a contact of the pressure gauge to receive the pressure signal. The analyzing module 210 is configured to cooperate with the first, second, third, and fourth input ports (204, 206, 208, 214) to receive the disconnect-switch status signal, the earth-switch status signal, the VPI state signal, and the pressure signal upon operation of the first limit switch. The analyzing module 210 is further configured to cooperate with the memory 202 to analyze the received signals and generate the electrical signal based on the pre-determined set of output generation rules. In an embodiment, the memory 202 includes a library of audio components and the pre-determined set of output generation rules include rules for selecting audio components from a library for generating the electrical signal. The output port 212 is further configured to output the electrical signal to the speaker 116. The speaker 116 generates sound output for assisting the operator to make decisions while working on the distribution switchgear 102 based on the received electrical signal. In an embodiment, the library and the pre-determined set of output generation rules can be programmed to facilitate generation of sound output in a required language.
In an embodiment, the analyzing module 210 includes a signal conditioning unit and a processor. The signal conditioning unit is configured to cooperate with the first, second, third, and fourth input ports (204, 206, 208, 214) to receive the disconnect-switch status signal, the earth-switch status signal, the isolator-VPI state signal, and the pressure signal and is further configured to generate values corresponding to the status of the disconnect switch 110, the earth switch 118 and the state of the VPIS 112. The memory 202 is configured to receive and store the generated values. The processor is configured to check if the values corresponding to the status signals, state signal, and pressure signal are present in the memory 202. Upon detecting the presence of said values, the processor is further configured to generate electrical signals for the speaker 116 based on the pre-determined set of output generation rules.
In an embodiment, the pressure gauge of the distribution switchgear 102 is provided with at least one contact. The contact may be a Normally Open (NO) or a Normally closed (NC) contact. The pressure gauge continuously monitors pressure of the isolating gas (for example, SF6) within the distribution switchgear 102. When the measured pressure falls below a safe operating pressure value, the contact of the pressure gauge changes state. The pressure signal indicates the state of the contact. Based on the pressure signal and the pre-determined set of output generation rules, the control unit 114 is configured to detect an unsafe operating pressure condition, and is further configured to generate and provide a first electrical signal to the speaker 116 for facilitating generation of a sound output to notify the operator about the unsafe operating pressure.
In another embodiment, the control unit 114 is configured to detect a safe operating pressure condition based on the received pressure signal and the pre-determined set of output generation rules, and is further configured to generate and provide a second electrical signal to the speaker 116 for facilitating generation of a sound output to notify the operator about safe operating pressure.
For example, if the pressure measured within the distribution switchgear 102 is below the safe operating pressure value, the control unit 114 generates an electrical signal to make the speaker 116 generate a sound output saying “Gas pressure is low. Please do not operate.” Thus, the operator is alerted about the low pressure and operator safety is ensured.
In an embodiment, the control unit 114 is configured to detect an unsafe condition for operating the earth switch 118 based on the received earth-switch status signal, VPI state signal, the said pre-determined set of output generation rules, and is further configured to:
i. generate and provide a third electrical signal to the speaker 116 for facilitating generation of a sound output to notify the operator about the unsafe operating condition; and
ii. generate a trigger signal to activate an electrically operated mechanical switch for restricting the operation of the earth switch 118.
The control unit 114 is configured to de-activate the electrically operated mechanical switch when the access channel associated with the earth switch 118 is released. The electrically operated mechanical switch is de-activated by stopping the generation of the trigger signal. In an embodiment, the control unit 114 may be configured to stop the generation of the trigger signal after a pre-determined delay upon detecting release of the earth switch channel. The control unit 114 is configured to generate a fourth electrical signal if the unsafe operating condition is not detected, and is further configured to provide the generated fourth electrical signal to the speaker 116 for facilitating generation of a sound output to notify the operator about safe operating condition.
In an embodiment, the pre-determined set of output generation rules may include logic for detecting an unsafe condition. For example, the control unit may be configured to generate the trigger signal when the isolator cable is back-charged i.e. the VPI state signal is high. The sound output is generated to notify the operator about the detected unsafe condition and the trigger signal is provided to the electrically operated mechanical switch to restrict the operation of earth switch 118.
In an embodiment, the system 100 includes a second limit switch associated with each of the disconnect switches 110. The second limit switch is configured to operate upon detecting movement of an access channel of the associated disconnect switch. The control unit 114 is configured to cooperate with the second limit switch to generate and provide a fifth electrical signal to the speaker 116 for facilitating generation of a sound output to notify the operator about the disconnect switch 110 being operated. For instance, if the operator is trying to access the disconnect switch channel to operate it, the control unit 114 generates an electrical signal to make the speaker 116 generate a sound output saying, “You are operating isolator XXXX at XXXX RMU.”
In an embodiment, the system 100 is implemented as a stand-alone unit. In another embodiment, the system 100 is integrated with the distribution switchgear 102.
The present disclosure also envisages a method 300 for assisting operation of a distribution switchgear 102. The distribution switchgear 102 comprises a pressure gauge and at least two isolator legs 104. The pressure gauge is configured to monitor pressure of an isolating gas within the distribution switchgear 102. Each of the isolator legs 104 includes a disconnect switch 110, an earth switch 118, and a Voltage Presence Indicator (VPI) 112. The VPI 112 is configured to indicate presence of voltage across the associated isolator leg 104. Referring to Figures 3A and 3B, the method 300 comprises:
At step 302 - detecting, by a control unit 114, pressure of an isolating gas within the distribution switchgear 102, by receiving a state of a contact of the pressure gauge;
At step 304 - generating, by the control unit 114, a first electrical signal based on a pre-determined set of output generation rules, if the detected pressure is below a safe operating pressure value;
- receiving, by a speaker 116, the first electrical signal from the control unit 114;
- generating, by the speaker 116, a sound output based on the received first electrical signal to notify the operator about unsafe operating pressure;

At step 308 - detecting, by a first limit switch, movement of a channel associated with the earth switch 118;
At step 310 - receiving, by the control unit 114, signals corresponding to a status of the earth switch 118 and the state of VPI 112 associated with the isolator leg 104 upon the operation of the first limit switch;
At step 312 - detecting, by the control unit 114, an unsafe operating condition based on the received earth-switch status signal, VPI state signal, and the pre-determined set of output generation rules;
if an unsafe condition is detected-
At step 314 - generating, by the control unit 114, a third electrical signal;
- receiving, by the speaker 116, the third electrical signal from the control unit 114;
- generating, by the speaker 116, a sound output based on the received third electrical signal to notify the operator about the detected unsafe operating condition,
At step 316 - generating, by the control unit 114, a trigger signal to activate an electrically operated mechanical switch for restricting the operation of the earth switch 118 upon detecting the unsafe operating condition,
if an unsafe condition is not detected-
At step 318 - generating, by the control unit 114, a fourth electrical signal;
- receiving, by the speaker 116, the fourth electrical signal from the control unit 114; and
- generating, by the speaker 116, a sound output based on the received fourth electrical signal to notify the operator about safe operating condition.
In an embodiment, the method 300 includes the step (Step 324) of deactivating the electrically operated mechanical switch for unblocking the operation of the earth switch when the access channel of the earth switch is released.
In an embodiment, the method 300 includes the step (Step 306) of:
generating, by the control unit 114, a second electrical signal based on the pre-determined set of output generation rules, if the detected pressure is greater than or equal to the safe operating pressure value;
receiving, by the speaker 116, the second electrical signal from the control unit 114; and
generating, by the speaker 116, a sound output based on the received second electrical signal to notify the operator about safe operating pressure.
In an embodiment, the method 300 includes the following steps:
At step 320 - detecting, by a second limit switch, movement of a channel associated with the disconnect switch 110;
At step 322 - generating, by the control unit 114, a fifth electrical signal upon the operation of the second limit switch;
- receiving, by the speaker 116, the fifth electrical signal from the control unit 114; and
- generating, by the speaker 116, a sound output based on the received fifth electrical signal to notify the operator about the disconnect switch 110 being operated.
An exemplary pseudocode for implementing the functionality of the control unit 114 is as follows:
Read SF6_gas_pressure value;
Step 1- If (SF6_gas_pressure value > safe operating pressure value)
{
Output “It is safe to operate the RMU.”
}
If (disconnect-switch access ¬channel operated)
{
Output “You are operating disconnect switch XXXX at XXXX RMU”;
}
Else if (earth-switch access channel operated)
{

Read earth_switch_status value;
Read VPI_state value;
If (VPI_state value == YES)
{
- Output “please do not operate. This ground isolator cable is backcharged”
- Activate electrically operated mechanical switch for blocking the operation of earth switch
}
Else
{
Output “you are operating earth switch”
}
}
Else
{
Return to Step 1
}
Else
{
Output “please do not operate. Gas pressure is low.”
}
The system 100 and method 300 facilitate easy operation of the distribution switchgear 102 as the operator is constantly notified about various parameters such as SF6 gas pressure, status of switches (i.e. isolators, earth switch, load switch, etc.), and back charging in cables and guided accordingly. Thus, safety of the operator and the equipment is ensured. Further, the system 100 is compatible with existing Ring Main Units (RMUs) and other distribution switchgears.
The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a system and a method for assisting operation of a distribution switchgear that:
• facilitates easy operation of the distribution switchgear;
• notifies an operator about the disconnect switch being operated;
• restricts the operation of the earth switch upon detecting an unsafe operating condition;
• alerts the operator in time to prevent wrong operation of the switchgear;
• is compatible with existing Ring Main Units (RMUs) and other distribution switchgears;
• is backward compatible; and
• ensures operator and equipment safety.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.