Common Smart Inverter Profile (CSIP)

CSIP mandates TLS 1.2 with mutual authentication for all TCP/IP communications. This requires both the utility server and the smart inverter client to present valid X.509 certificates, ensuring a zero-trust architecture where every connection is authenticated and encrypted before any application data is exchanged. The profile explicitly forbids fallback to older, vulnerable protocols like SSL 3.0 or TLS 1.0.

CSIP requires inverters to support a specific subset of IEEE 2030.5 function sets to enable core utility operations:

• DER Control (Function Set 1): Allows the utility to command real power limiting, volt-VAR curves, and fixed power factor modes.
• DER Monitoring (Function Set 2): Mandates real-time telemetry of active power, reactive power, voltage, and connection status.
• DER Settings (Function Set 3): Enables remote configuration of grid-support parameters like ride-through curves.

Upon initial connection, CSIP-compliant inverters must default to an autonomous Volt-VAR control mode defined by IEEE 1547-2018 Category B parameters. The inverter actively adjusts its reactive power output (absorbing or injecting VARs) based on local voltage measurements to stabilize the distribution feeder. The specific curve points—including the deadband around nominal voltage and the slope of VAR response—are remotely configurable by the utility via the DER Settings function set.

CSIP defines strict timing requirements for data synchronization:

• Default Polling Interval: The utility server must poll the inverter for telemetry no more frequently than every 5 seconds to prevent network congestion.
• Event-Based Reporting: Inverters must immediately push unsolicited notifications for critical status changes, such as a cease-to-energize trip or a transition to islanded mode.
• Clock Synchronization: All devices must maintain time synchronization via NTP to ensure accurate event logging and coordinated control sequences.

CSIP specifies a Public Key Infrastructure (PKI) hierarchy. Every inverter must be provisioned with a unique, device-specific IEEE 2030.5 end-entity certificate issued by a trusted Certificate Authority (CA). This certificate binds the inverter's unique identity (SFDI) to its public key. The utility's server validates this certificate on every connection, preventing spoofing and ensuring that only authorized physical devices can receive grid-control commands.

To enable zero-touch provisioning on a local network, CSIP mandates the use of Multicast DNS (mDNS) . An inverter advertises its presence and its IEEE 2030.5 resource endpoint using DNS Service Discovery (DNS-SD). The utility's gateway or aggregator listens for these broadcasts to automatically discover new devices, retrieve their device capabilities, and initiate the secure registration process without manual IP configuration.