KCP&L provides energy-related products and services for homes and businesses in the Kansas City Metropolitan area and nationwide. Headquartered in downtown Kansas City, Missouri, KCP&L generates and distributes electricity to retail customers, cities and electric utilities in Missouri and Kansas.
They operate 4 plant sites with 18 units providing power to their customers and selling into the wholesale market for the central states region. Over 3,700 megawatts of efficient generation assets are in operation or under construction.
KCP&L was looking for a way to monitor capacitor banks in their service territory. In the past, they monitored non-communicating capacitor banks by having someone drive by and physically inspect them. This was time consuming and expensive.
KCP&L sought a two-way communications method that would be cost effective and work in the non-metro areas of their service territory. These two requirements (low-cost and wide area coverage) led them to Sensus.
Switched Capacitor Banks Solution
Approximately two-thirds of KCP&L’s cap banks are switched, operating with EnergyLine 1000 Series capacitor controllers. These devices are DNP3 compliant, so KCP&L selected the Sensus DNP-RTM (Remote Telemetry Module) for this application. Using an RS-232 connection with the EnergyLine 1000, the DNP-RTM enables wireless communication for monitoring and controlling the capacitor bank.
The goal of automating these switched capacitor banks was to correct power factor and voltage deviations. Now, KCP&L is able to quickly respond to fluctuating power demand using the DNP-RTM.
The Sensus RTM allows KCP&L to monitor cap bank status (open or closed), line voltage and phase angle. When necessary, KCP&L can now open or close the capacitor bank without a site visit.
The DNP-RTM operates as a master, polling the EnergyLine 1000 for digital and analog values. Whenever the DNP-RTM receives a reportable value (e.g. a digital input state change), it immediately reports this to the Network Operations Center (NOC).
The low cost of the Sensus solution allows KCP&L to extend automation as close as possible to rural customers. While these cost savings were used to initially justify the project, KCP&L has also been able to identify issues and respond to equipment problems and outages much faster.
Fixed Capacitor Banks Solution
The other one-third of KCP&L’s capacitor banks are fixed. For these devices, KCP&L chose the Sensus TC012. This Sensus MicroRTU detects operating anomalies such as blown fuses, stuck switches, or damaged control cables by measuring and reporting any significant changes in the state of the neutral current. Status reports can also be time scheduled in advance or requested at any time.
The analog input sensor converts the 0-100 Amp capacitor bank neutral current to a 0-10 Volt AC signal. A neutral current of zero indicates that the installation is switched out of service. Normal neutral current (a nominal value above zero) when the bank is closed indicates the bank is switched in service and the installation is operating as expected. A neutral current that is higher than average but below a predefined limit indicates the presence of high harmonic current or resonant conditions, which may indicate a partial pack failure. A higher, pre-defined level of current indicates a blown fuse or other serious problem.
The TC012 also includes easily accessible switches for local control. The local/remote switch physically disables remote operation, and the status of the switch is reported when changed. A local control delay gives operators time to move a safe distance from the equipment before the output change is made.
After completing their initial installation and study of the Sensus technology for monitoring and controlling capacitor banks, KCP&L would like to use this same technology for other distribution automation applications – particularly in the outlying areas of their service territory. They plan to work with Sensus on the automation of switches, regulators, reclosers and fault detectors, as well as remote voltage monitoring.