Automated Monitoring and Control

UTILIZATION OF SCADA

Since 2006, TNB has deploy Supervisory Control and Data Acquisition (SCADA) projects within our 11kV distribution substations. These initiatives are instrumental in achieving our objective of enhancing the availability and reliability of the distribution network system through real-time monitoring and control of field equipment. Such efforts are pivotal in our commitment to the establishment of a Smarter Grid and the acceleration of Distributed Energy Resources (DER).

With the use of SCADA technology, Advance Distribution Management System (ADMS) and Intelligent Electronic Device (IED) installed at substations, TNB Control Centers are now able to obtain real-time data monitoring and control of network assets, thus enabling quick identification of fault location and informed-decision making to restore supply within a short period of time. A control center is equipped with various capabilities and tools such as:

1. Real-Time Monitoring

The control center continuously monitors the status of the distribution network in real-time. This includes monitoring voltage levels, current flows, equipment status and power quality.

2. Data Acquisition and Analysis

It collects and analyzes data from various sensors and intelligent electronic devices (IEDs) located throughout the distribution network.

3. Alarms and Event Management

The control center receives alarms and events triggered by sensors and IEDs.

4. Remote Control

Operators can remotely control various components of the distribution network, including switches, circuit breakers and reclosers. This capability allows for the isolation of faults and the restoration of services in a shorter time frame as compared to manual switching at site.

5. Load Management

The control center can balance loads within the network to prevent overloading and reduce inefficiencies. It may include load shedding capabilities to maintain grid stability during peak demand.

6. Outage Management

The control center helps in identifying the location and cause of outages, allowing for quicker response and restoration efforts. It can also estimate the number of affected customers.

7. Asset Management

It assists in monitoring the condition of distribution network assets and helps schedule maintenance activities to prevent equipment failures.

8. Network Reconfiguration

The control center can reconfigure the network by opening or closing switches to optimize power distribution, reduce losses, and enhance reliability.

9. Integration with DERs

As more Distributed Energy Resources (DERs) are integrated into distribution networks, control centers need to accommodate these resources and manage their interactions with the grid effectively.

10. Cybersecurity

Implement robust cybersecurity measures to protect the control center and the distribution network from cyber threats and unauthorized access.

11. Predictive Analytics

Use advanced analytics to predict equipment failures, assess the impact of weather events, and optimize network performance.

12. Customer Interaction

The control centers also have customer interaction features to communicate with consumers during outages, provide estimated restoration times, and receive outage reports from customers.

13. Microgrid Control

For networks with microgrids, the control center can manage the operation of these smaller grids within the distribution network.

A well-designed control center is paramount to effectively manage the distribution network, optimizing power quality, minimizing downtime, and bolstering overall grid reliability. The figure below underscores the pivotal role of the control center in continuously monitoring and maintaining the distribution network at peak performance levels.

Figure 1A. 1: Interaction between control center and distribution network

DISTRIBUTION AUTOMATION

Distribution Automation is one of the foundation in building a utility with Smart Grid capabilities. It involves the use of advanced control, monitoring, and communication technologies to enhance the management and operation of power distribution networks. The primary goals of distribution automation are to reduce the outage duration, improve power quality, and optimize the use of distribution assets. In addition, it enables Control Center with various capability such as to monitor and control the interconnection of Distributed Energy Resources (DER) and able reduce the risk of accidents among operational personnel.

In TNB, a dedicated project team known as Distribution Automation (DA) was formed to install various equipment such as Remote Terminal Unit (RTU), Field Terminal Unit (FTU), Motorized Switchgear and other IED equipment at all types of substations (PMU – Main Intake Substation, PPU - Primary Distribution Substation, SSU - Switching Station and  PE - Substation) at various voltage levels (132kV, 33kV and 11kV). The system uses fiber and wireless communication medium as appropriate on site. The diagram below shows the overall installation of DA and ADMS in Distribution Network.

Figure 1: Type of equipment to enable remote monitoring and control

Figure 2: ADMS and Distribution Automation Infrastructure in TNB Distribution Network

DA Project is set to continue strengthening the distribution network in the coming years for more efficient and reliable system. The laid out plans for DA Project is to achieve cumulative installation of 41% of the total substations in Peninsular Malaysia by end of 2024, 64% by end of 2027 and 84% by end of 2030.

Figure 3: The roadmap of DA penetration until 2030

In year 2023 until now, DA Project has successfully installed and commissioned 4,926 substations covering an estimation of 2.6 million customers. This brings our total DA installation from 2014 onwards to 28,926 distribution substations in Peninsular Malaysia.

ADVANCED DISTRIBUTION MANAGEMENT SYSTEM (ADMS)

TNB DN’s Advanced Distribution Management System (ADMS) is developed to replace the existing Distribution Management System (DMS). ADMS, a software platform integrating several utility systems applications provides automated capabilities for timely outage restoration and optimization of the distribution grid. This translates into a higher performance, reliability in providing solution for reducing technical losses, enhanced work safety, shortened service restoration time during outages, and increased grid resiliency to natural disasters and other threats that could disrupt the flow of power to the end-user.

The energy value chain is a complex network that encompasses various layers of energy sources and distribution equipment. This includes conventional legacy power plants, transmission lines connecting power plants to distribution networks, and existing low-voltage power distribution networks. However, in recent years, the energy value chain has witnessed significant changes with the introduction of new equipment and technologies such as:

1. Renewables and Large-Scale Solar Farms

One of the notable additions to the energy value chain is the incorporation of renewables, particularly large-scale solar farms. These renewable sources are changing the way we generate and distribute energy.

2. Battery Energy Storage Systems

Battery energy storage systems have become an integral part of the energy value chain, allowing to store and manage energy more efficiently.

3. Local Solar Farms

The emergence of local solar farms is transforming energy generation at a community level, making it more sustainable and decentralized.

4. Distributed Energy Resources (DER)

 DERs, which include various distributed energy sources, are becoming increasingly important in diversifying the energy mix and improving energy resilience.

5. Electric Vehicle Charging

The growing electric vehicle (EV) industry has necessitated the integration of electric vehicle charging infrastructure into the energy value chain.

The changes in the energy landscape have led to an evolution in the roles of TNB DN. They are no longer just passive carriers of electricity but have transformed into active players in the energy transition i.e.:

1. Operator of Network

TNB DN operators are now responsible for efficiently managing the grid, ensuring a stable supply of energy, and facilitating the integration of new energy sources.

2. Facilitator of Energy Transition

Play a crucial role in facilitating the transition to a more sustainable and renewable energy future.

3. Enabler of Customer Empowerment

Empower customers by providing them with more control over their energy management as well as to cater for future energy exchange and trading.

To align with this evolution, distribution network operators have expanded their roles to:

1. Efficient Network Management

Focus on efficiently managing the network, optimizing energy flows, and reducing wastage.

2. Increased Supply Reliability

Ensuring a reliable supply of energy to consumers remains a top priority.

3. Fast DER Connection to Grid with Bi-directional Power Flow

Adapting to accommodate the rapid integration of DERs and enabling bidirectional power flow to support the grid.

As facilitators of the energy transition, TNB DN are driving several key initiatives:

1. High Renewable Energy (RE) Penetration

By 2025, TNB DN aim to achieve high levels of renewable energy penetration within the grid, reducing reliance on traditional fossil fuels.

2. Promoting EV Industry Growth

Distribution networks actively support the growth of the electric vehicle industry by facilitating widespread EV charging infrastructure.

3. Reducing the National Carbon Footprint

By encouraging the adoption of cleaner energy sources and technologies, TNB DN contribute to a reduction in the national carbon footprint, helping combat climate change.

The roles undertaken by ADMS is to ensure customer empowerment is supported by providing the enabler for self-energy consumption and digitalization engagement.

The table and diagram below explains on the journey of ADMS implementation in TNB DN:

ADMS Functions and Capabilities in TNB DN

1. The Regional Operation Control Centre offers SCADA and DMS functionalities, along with the ability to process geographic map data (GIS). It furnishes operators with comprehensive operation displays and dispatching details. In the event of an incident, it aids operators in promptly recovering power in affected upstream and downstream sections. The system's expandability accommodates the inclusion of feeders and substations across the entire district within the Distribution Feeder Automation framework.
2. ADMS can monitor various substation information terminal equipment feeder via Remote Terminal Unit (RTU) & Field Terminal Unit (FTU) and other equipment installed on distribution network.
3. Supervisory Control and Data Acquisition (SCADA) function which allows TNB to monitor and control of automated switches, and devices within substation through geographic display for electrical network topology.
4. Outage Management System (OMS) is a comprehensive solution designed to efficiently manage and respond to power distribution outages and related issues. It combines advanced technology to streamline outage information, restoration processes, and the coordination of field operations. This integrated system serves as a powerful tool for utilities to enhance their grid management capabilities, minimize downtime, and improve overall service reliability with integrated systems.
5. DER Visibility allows operators to monitor the operation of the distributed energy resources in real-time. It empowers TNB to maximize the benefits of distributed energy resources while ensuring reliability and efficiency in energy delivery.

Figure 1: Peninsular Malaysia Geographical Distribution Network

Geographic display for Operations through GIS CIM Integration

A geographic display for operations through GIS CIM integration provides a visual representation of the power distribution network using Common Information Model (CIM) data, enabling operators to monitor and manage the grid with geographic context and real-time information.

Figure 2: Geographical Display in ADMS Medium Voltage

Find Location Function

Navigate easily to display from alarm event list, devices, substation, incidents & customers.

Figure 3: Find Functionalities to Locate the Incident

Single Line Diagram (SLD)

Feeder schematic display based on electrical network topology.

Figure 4: Network As Build View

Circuit Breaker status on feeder level schematic display based on electrical network topology.

Figure 5: Internal View to Observe the Detail in Substation

Substation Information Readily Available in Substation View

Enable operator to understand the network status with a glance.

Figure 6: Main Intake Substation View in ADMS

Fault Location, Isolation & Service Restoration (FLISR)

Fault Location, Isolation, and Service Restoration (FLISR), a critical functionality within ADMS is designed to automatically detect, pinpoint the location of faults or disruptions in the distribution network, isolate the affected areas, and quickly restore service to minimize outage durations.

It is represented by a set of applications used for locating and isolating faults, as well as restoring power supply to de-energized customers. The applications are as below:

• Fault Location (FL) - this application is used to quickly pinpoint a group of feeder sections where an electrical fault may have occurred. The number of sections identified as potentially containing the fault depends on the extent of fault measurement equipment installed in the network.  If there are many, it can pinpoint the issue to a specific section; otherwise, it gives a broader section of where the fault might be.

• Fault Localization (FLL) – this application provides location and isolation functionality for feeders with fewer fault location equipment installed. The FLL application feeds the Switching Sequence (SS) module with a proposed switching procedure, enabling remotely and/or manually controlled switching operations to pinpoint and isolate the faulted section.

• Fault Isolation (FI) – the FI application provides the SS module with the faulted element or set of elements resulting from the FL/FLL analysis and isolation.

• Supply Restoration (SR) – The SR application furnishes an optimal operational plan to reinstate service to the unaffected section of the feeder following the isolation of the faulty element. The outcome of the SR application is a series of switching sequences, prioritized based on the user's selected criteria.

• Restore to Normal State (RN) – The RN application generates the switching sequence, detailing the operations necessary to restore the network to its normal or pre-fault state—the state it was in before the fault occurred.

Figure 7: FLISR Status in ADMS

SCADA in DMS Functionalities

ADMS power applications like Fault Calculation, Relay Protection, and Volt Var Optimization rely on estimated current derived from the State Estimation (SE) function. The SE is used to assess (estimate) the distribution network state considering:

• Remotely monitored data (SCADA) such as breaker status, current & voltage measurements, tap changer positions, etc.

• Initial load data which is derived from the load curves given in the model or from the previous estimated state

The model incorporates various measurements, including voltage magnitudes of MV busbars, current, and real and reactive power measurements from distribution transformers. These measurements also encompass results from EMS State Estimation (from TNB Grid) for boundary nodes between EMS and DMS networks, such as estimated voltage magnitude and phase angle, as well as injected real and reactive power. These estimation procedures rely heavily on real-time telemetry redundancy and the availability of switchgear statuses provided by SCADA systems.
 

SCADA in Outage Management System (OMS) Functionalities

Through SCADA signals, the Outage Management System (OMS) receives reports on forced outages, leveraging SCADA information such as breaker status to pinpoint faulted sections of the network. Additionally, the OMS provides estimated power loss based on Distribution Management System (DMS) analytics, offering comprehensive reports detailing affected transformers, customers, load loss, and other pertinent information.

This integrated service shares information with TNB DN’s work management system i.e. MVORR, empowering crews with incident details. Crews can then provide updates on the incidents as they work on restoration efforts. Furthermore, the OMS generates restoration switching sequences for Fault Location, Isolation, and Service Restoration (FLISR) and force outages. This collaborative ecosystem enhances the restoration process significantly.

Planned Interfaces with Other Systems to Realize ADMS Advance Functionalities 

• Integration with Geospatial Information System (GIS) for network model & topology.
• Integration with Advance Metering Infrastructure (AMI) for smart meter information.
• Integration with Smart Work and Asset Total Solution (SWATS) for crew model & crew status.

Figure 8: End-to-end System Interface for DN Operations

Distributed Energy Resources Management System (DERMS) in ADMS

In the ADMS setup, DERMS plays a crucial role in actively monitoring Distributed Energy Resources (DER) within the MV network such as solar panels, energy storage system and electric vehicles. DERMS enables DN operators to monitor the operation of these distributed energy resources in real-time. By balancing supply and demand, integrating renewable energy sources, and improving grid stability, DERMS plays a pivotal role in the transition towards a more sustainable and resilient energy system. With features such as monitoring, control, grid integration, optimization, and forecasting, DERMS empowers TNB to maximize the benefits of distributed energy resources while ensuring reliability and efficiency in energy delivery.

DERMS in ADMS provides valuable insights into power flow, with connectivity extending up to the circuit breaker level. ADMS analyses data received from the DERMS at the circuit breaker connected to the MV substation. Leveraging this data, ADMS predicts energy production based on power flow and the rated power of Distributed Generation (DG) resources. This predictive capability enables a comprehensive understanding and efficient management of electricity flow from these distributed energy resources into neighbouring networks. With DERMS in place, opportunities for implementing controllability and optimization measures may emerge with revision in the Distribution Code in progress.

Success Stories

1. Reduction of Restoration Time from Total Unplanned Outage

Through the implementation of SCADA and Distribution Automation, the substation became an intelligent hub of real-time data. These units continuously collected and analyzed data from various parts of the network, detecting fluctuations, overloads, and equipment failures instantaneously. As soon as an issue was detected, the RTUs sent automated alerts to the network operators for rectifications.

TNB DN observed an average of 17% reduction of restoration time from total unplanned outage, whereby majority of the outage are being restored within 15 minutes.

Figure 9: Reduction of restoration time with DA

Since operators can remotely monitor equipment health and performance, detect issues or anomalies, and take corrective actions without physically visiting the site, this minimizes the need for frequent site visits and reduces traveling costs. It also enables allocation of resources more efficiently i.e. field crews can be dispatched based on actual need, rather than following a rigid schedule, further reducing travel and crew costs.

Furthermore, with the implementation of ADMS, TNB DN has the holistic capabilities in enhancing the efficiency and reliability of our grid operations in term of:

• Network Visibility i.e. enhancing network visibility to facilitate more DER connections to the network
• Enabling self-healing grid – along with DA and VVO, ADMS serves as foundation to establish self-healing grid capabilities.
• Improving Safety - DA are main enabler to elevate safety standards during grid switching operations.
• Enhancing system reliability & security to improve business continuity.

2. The World's First Operational GIS-ADMS Integrated Network Model Automation.

GIS-ADMS Integration was established substation and medium voltage feeders successfully imported into ADMS from GIS data model. GIS-ADMS integration is one of the critical paths as Operational Data Model Integration pose huge challenges to convert the static data model to dynamic operational data within Common Information Model framework. This success makes TNB the first in the world to establish Operational GIS-ADMS Integrated Network Model Automation using Integration Standard Common Information Model CIM: IEC 61968/61970 and 62325.

Figure 10: World's First Operational GIS-ADMS Integrated Network Model Automation