CCI – Central Plant Controller

Legislation requires 3 functional categories: mandatory, optional and voluntary.

• PF1: The first group refers to mandatory monitoring functions.
• PF2: The optional functions are activated at the discretion of the DSO, are related to the remote control of the system and regulate the voltage and frequency of the network.
• PF3: Voluntary functions are activated at the discretion of the manufacturer and relate to plants in the dispatching service markets and include optimised management of the plant and loading in start-up or reconnection.

It better be. Indeed, the CCI must use a PKI (Public Key Infrastructure) for the management of security certificates (see CEI 0-16 T.3.3.4.9).

According to Annex T there are 3 ways to do this:

1 – Manual Management (temporary solution only): Installations, updates, revocations, replacements of the DSO certificates and any BSPs must be done manually on each plant. Challenging and error-prone if there are many CCIs to manage.

2 – Local PKI in the plant and OCSP protocol: Installing and managing a local PKI is very expensive and difficult. It is neither convenient nor safe.

3 – External PKI in the CLOUD: The CCI uses an external PKI in the #cloud, through the internet connection. Secure, centralized and automatic certificate lifecycle management.

Furthermore, a CCI connected to the internet is easier to update – mandatory updates are already foreseen in the coming years – to reach and consult – through our portal – to be replaced in case of failure – automatic backup of configurations and data.

The CEI 0-16 2022-03 standard requires the following data to be collected:

• Delivery Point: measurement of P, Q, V and optionally I. DG and DI status
• Single Generators: P and DDG status

The CEI standard requires the measurements of the individual generators only if they have a rated power greater than:

• 170kW for static converters (e.g. photovoltaic inverters)
• 250kW for traditional generators
• 50kW for storage

Furthermore, the Arera Resolution 540/21 in Article 2 indicates that the measurements of the individual generators are required only for new plants. For the measurements, the precision required is that indicated in tables 5 and 6 of Attachment A.6 Terna: maximum measurement error less than or equal to 2.2%. For existing single generators only, the maximum error rises to 10%.

The control functions of the CCI are based on closed-loop regulators. These regulators read the measurements at the delivery point, compare them with the set points, which are received (slave mode) or calculated (autonomous mode), calculate the set points to be sent to generators/converters and send them. Consequently, the CCI must be able to communicate reliably and quickly with the generators/converters, which must implement a standard communication interface and protocol which provides for the possibility of receiving commands in P and Q (or equivalent, for example PF or PHI ). If the communication is based on serial protocols, such as RS485 or CANBUS, and not Ethernet, it is more difficult to respect the prescribed response times, and it is necessary to evaluate the feasibility case by case.

Many photovoltaic inverters, even very old ones, were already set up to be regulated by a centralized control system, i.e. they offer a standard communication protocol with registers that can be used to send commands in P and Q (or equivalent). To verify compatibility, you can check the product manual or the document describing its communication protocol. We have been in the PV system control business for almost 10 years, and so far we have only encountered one brand of inverter that was totally uncontrollable.

Once all the tests have been carried out and the certifications have been obtained, as described in chapter O.15 of CEI 0-16 2022-03, CCI manufacturers will be able to issue a self-declaration of conformity to the standard, Annexes O and T. The technical file, thus obtained, must be kept for at least 10 years starting from the last date of manufacture of the product and must be kept at the disposal of the control authorities. A third party, accredited for these attachments to the standard, can certify the conformity of the product, as an enhancement to the self-declaration.

Chapter O.15 of CEI 0-16 2022-03 specifies stringent requirements for both hardware and software cyber security. In particular, the use of a cryptographic component capable of detecting and responding to physical tampering is required, certified according to FIPS-140-2 with level 3. Certification to IEC 62443-4-1, according to the scheme, is also required IsaSecure Secure Development Lifecycle Assessment (SDLA), of the CCI production process, and to IEC 62443-4-2, according to the IsaSecure Component Security Assurance (CSA) scheme, of the CCI product.

No, the CEI 0-16 Annex O standard requires various tests, which cannot be carried out in any laboratory. To comply with the standard, the product must pass the insulation, EMC, immunity to interference, and climatic tests in an ISO 17025 accredited laboratory, and the functional tests in the presence of an ISO 17065 accredited inspection body.

Once all the tests have been passed, the relative test and inspection reports obtained, and the required certifications obtained, at which point the manufacturer self-declares that the CCI complies with CEI 0-16 Annex O and T. The technical file with all the test reports and certifications, must be kept and kept available for 10 years.