Challenges

Improving Distribution Line Voltage Control Methods

Smart Meter Data Utilized for Coordinated Control of MV Voltage Regulators

Background

Fig. 1. Hosted capacity of PVs in Chubu area.

More PVs are expected to be connected to the power grid as expectations grow for a carbon-free society.
Most PVs are installed on MV and LV distribution networks causing voltage rises. To minimize investment, it is crucial to manage these voltage rises with the fewest voltage regulators. This will be achieved by utilizing real-time metered data and introducing coordinated, automatic and remote control of regulators.

Proposal

Utilizing smart meter as sensing devices to ascertain load consumption and PV output

By utilizing smart meter (SM) data along with data from sensor-equipped switchgears, actual load consumption and PV output of every customer will be thoroughly ascertained. Based upon that data, network voltage can then be calculated. We define the SM system as “Advanced Metering Infrastructure (AMI)” rather than “Automatic Meter Reading System (AMR).” This is one instance of using smart meter data as AMR.

Fig. 2. Example of the calculated results

Remote control of voltage regulators based on ascertained load consumption and PV output (development of grid control system and advanced voltage regulators)

In order to realize coordinated control of regulators, a new system, the Grid Control System (GCS), has been developed, which appropriately calculates voltage regulator control parameters. Moreover, advanced voltage regulators, enabling the GCS to monitor and modify parameters remotely, have been developed in tandem with the GCS. Figure 3 shows the flow of GCS data from collection to parameter setting.

GCS uses the following data:

Power current and voltage data measured by section switch gear equipped with sensors on MV distribution networks
Power consumption/generation data measured by smart meters (SM)

Using the collected data, GCS calculates optimal parameters for each time interval (every 30 minutes) and remotely sets the parameters for advanced voltage regulators.

GCS started operation in June 2021. We have verified that GCS is functioning effectively to maintain appropriate voltage (Figure 4)

Fig. 4. Effect of advanced method compared with conventional method

Future Plans

We are planning to further develop these proposals, such as by actively controlling distributed energy resources (DER) represented by battery and EV, in order to realize an efficient and resilient distribution network, a key component for realizing a carbon-neutral society.