Ford Charge Station Pro Home Backup System - Technical Review
This is a detailed insight into the function and features of the Ford Charge Station Pro and Home Integration system which together form Ford’s unique bidirectional charging system. Note, that some operating functions have been assumed based on the limited technical information available.
The Ford Charge Station Pro together with the (optional) Home Integration System create what is known as a bidirectional EV charging system to provide backup power. While bidirectional EV chargers have been available for several years, the technology is still in the trial phase. In most countries, it is not known precisely when the regulatory framework and standards will be fully established to enable these devices to connect to the local electricity networks. Despite the setbacks, manufacturers such as Ford are pushing ahead to develop bidirectional EV chargers, and vehicle manufacturers are adding bidirectional charging capabilities into many new model EVs.
Ford Charge Station Pro
The Ford Charge Station Pro is one of the most talked-about bidirectional charging systems in the US. It is compatible with the much-hyped Ford F150 Lightning electric pickup and is required to enable what Ford has dubbed intelligent backup power. Unlike other universal bidirectional chargers, the Charge Station Pro is a Ford exclusive product rated at a maximum of 80-Amps, or 19.2kW, making it one of the most powerful single-phase level-2 chargers available. The charger was developed in collaboration with Siemens eMobility and enables bidirectional charging to power a home with up to 9.6kW, but only when installed together with the Home Integration System described in detail below.
The Charge Station Pro is both Bluetooth and Wi-Fi-capable for easy setup and monitoring via the FordPass App. The App provides detailed charging and vehicle information plus a number of charging options including charge scheduling and remote operation. The charger is weatherproof and equipped with an Industry-standard CCS connector which is compatible with Ford and many other electric vehicles.
Ford Charge Station Pro electrical specifications and requirements
Download the full Ford Charge Station Pro datasheet.
How the Ford Charge Station Pro works
On its own, the Ford Charge Station Pro functions much like any standard wall-mounted EV charger but uses the standard CCS1 (Combined Charging System) connector*. However, unlike regular chargers which are limited to 40A, Ford’s system can charge at a much higher rate of 80A (19.2kW) from a single-phase 240V supply.
* Note, that the previous Ford Charge Station Pro datasheet listed the industry-standard SAE J1772 connector, also known in North America as the J-plug. It now lists the CCS1 (AC & DC) connector.
It has been challenging to find reliable technical information about how the Charge Station Pro, or more specifically, how the home integration system functions as a bidirectional charger. Being based in Australia, I haven't had the opportunity to personally talk to Ford or examine the product closely. Luckily, a few very good in-depth videos have provided some valuable insight, such as this one from State of Charge. Also, this interesting video from Engineering explained comparing a Tesla Powerwall with the F150 EV for energy storage purposes. Based on the information available we have put together a power flow diagram to describe the system below.
Ford Home Integration System and EV charger power flow diagram with backup essential loads
Is the Charge station Pro a true Bidirectional charger?
We know the Charge Station Pro can function as a conventional EV charger and uses the AC portion (J-plug) of the CCS1 connector to charge an EV using AC power, much like a regular charger. What is very different is that it uses the DC (fast-charging) pins in reverse to discharge energy from the vehicle and provide backup power. However, bidirectional charging is only possible with the (optional) Ford home integration system, which contains the power conversion equipment. With this in mind, I would not classify Ford's system as a bidirectional charger in the same way I would the Wallbox Quasar. Unlike the Quasar, Ford’s system does not (yet) appear to offer vehicle-to-grid (V2G) functionality as it is not fully grid-interactive and can not synchronise with the grid. However, considering Ford's charge station Pro is UL certified and meets the bidirectional charging standard UL 9741, it would be safe to assume the full grid-interactive features are in development or not yet enabled. In its present form, I would describe Ford's set-up as an advanced vehicle-to-load (V2L) system that functions as a full home backup power supply. Until the V2G functionality is validated, it's backup power only. We will know more when Ford releases the full hardware specifications of the Home Integration System.
Learn more about the difference between V2L, V2H and V2G
Detailed power flow electrical schematic of the Ford Charge Station Pro and Home Integration System.
Regarding the hardware, Ford's decision to separate the EV charger and inverter is clever in that it provides multiple configuration options and gives the ability to upgrade at a later stage from a relatively low-cost EV charger to a full backup power system. Another benefit of a modular system is that the home integration system, which contains the power conversion equipment (inverter), can be co-located close to the main distribution board, making it much easier to integrate, while the charger can be located closer to the vehicle parking location.
Bi-directional charging technical insight
The following section describes the technical aspects of (V2G) bidirectional charging and the grid synchronisation requirements needed for any generation source to safely inject energy into a network. This is similar to the operating principles of commonly available (bidirectional) inverter-chargers used for hybrid (solar and battery) power systems explained in detail below.
Grid Synchronisation
For any generation device to deliver power into an AC electricity grid, whether a spinning turbine or an inverter-charger, it must first be operating at the same frequency as the grid network; meaning, it must synchronise with the grid. In Australia and most of the world, the grid frequency is 50Hz, while North America uses 60Hz (60 cycles per second). In order to synchronise, the inverter must match not only the frequency but also the voltage and phase angle.
Bidirectional chargers used for V2G are designed to export power into the electricity grid, typically during times of high demand to help stabilise the grid. For a system to inject power into the grid, it must do so at a voltage slightly higher than the grid voltage. Solar inverters have been operating on exactly the same principle for decades, as have modern hybrid inverters, which are used for residential energy storage. For example, if the grid were operating at 238V, the inverter would need to maintain a voltage slightly higher for the current to flow in the right direction. The grid voltage is rarely stable, and inverters use onboard high-frequency controllers and sensors to adjust the output voltage and maintain constant export power.
Grid-interactive inverter-charger
While bidirectional EV chargers are a very new technology still mostly in the trial phase, grid-interactive inverter-chargers, known simply as inverter-chargers, have been around for over a decade and are used for both off-grid and on-grid solar energy storage systems. These sophisticated inverters are unique in that they can function as both grid-following inverters and grid-forming (off-grid) inverters. As explained previously, solar inverters must also synchronise with the electricity grid to inject power; Inverter-chargers work in the same way but are capable of bidirectional power flow. Bidirectional EV chargers used for V2G are essentially the same and are also capable of two-way power flow, the only significant difference is the battery is inside a vehicle.
NOTE: This article will be updated as more information comes to light. If anyone has (inside) technical specifications or photos of the internals of the home integration system, please feel free to contact me at jason@cleanenergyreviews.info.
