Pierre Pelletier

The interphase power controller: a new concept for managing power flow within AC networks

The paper presents a new concept for controlling the flow of power within AC networks. The application is based on the series connection of impedances between different phases of the two (synchronous) subnetworks to be interconnected, hence its name: the interphase power controller (IPC). The IPC acts as a current source with the following characteristics: the power flow is nearly constant (within 10%) for a wide range (/spl plusmn/25/spl deg/) of angle between the two subnetworks; there is no significant short-circuit contribution from one network to the other; severe contingencies on one side of the IPC have negligible impact on the voltage of the other side; no harmonics are generated (because there is no control action). Other operating conditions (reduced power, reactive power generation or absorption) are possible by switching impedance components. In all cases, the IPC comprises only conventional elements (transformer, capacitors, reactors and circuit breakers). >

Interphase power controller with voltage injection

This paper introduces a new family of interphase power controllers (IPC) based on the principle of voltage injection commonly used in phase-shifting transformers (PST). The voltage injection IPC exhibits power (active and reactive) control characteristics similar to previously defined IPCs and retains their inherent qualities: passive control, short circuit limitation and voltage decoupling. It also provides more flexibility for the adjustment of the operating point. Two promising topologies are described in more detail. One of them offers the potential of retrofitting existing phase-shifting transformers into full-fledged IPCs. The application of the IPCs is in flexible AC transmission systems. >

The IPC technology-a new approach for substation updating with passive short-circuit limitation

The paper presents a new approach to fault current limitation based on the interphase power controller (IPC) technology. From a power system point of view, this IPC has the same function as a transformer: it handles its share of the load current but, during a fault, it does not contribute to the fault current. It thus allows a substation to be updated without increasing the fault level. A four-transformer 315-120 kV substation is used to illustrate the concept.

Application of the interphase power controller technology for transmission line power flow control

This paper presents an application of the interphase power controller (IPC) technology for controlling power flows while maintaining the natural synchronizing capacity of transmission lines. The benefits for transmission systems are a substantial increase in steady-state transmission capability, lower losses and voltage support. An example based on the 500 kV Mead-Phoenix Project demonstrates the effectiveness of the IPC solution: the addition of a 370 MVAr capacitor in parallel with the two 500 kV phase-shifting transformers increases their maximum capability from 1300 to 1910 MW. The concepts presented are the results of the first phase of work leading to the development of an IPC using power electronics.

Interphase power controller adapted to the operating conditions of networks

This paper introduces a new family of interphase power controllers (IPC) for which the useful portion of the P/sub r/-/spl delta//sub sr/ characteristics are shifted as the power transfer level is increased. Thus, the power characteristics of a specific IPC application can be adapted to the operating conditions of the power network. The response of the IPC is compared to those of the two conventional technologies used in building it: the phase-angle regulator; and series compensation. It is shown how the natural response of the IPC regulates active power passively, without the need for control action. Also, reactive power can be controlled independently of active power slowing for better voltage control. The new IPC retains the inherent qualities of previous IPCs. >

The design of a 200 MW interphase power controller prototype

The paper addresses the practical design aspects of a 200 MW prototype for the interconnection of two synchronous 120-kV networks that are close to their short-circuit limits. The interphase power controller is a new concept for the control of active and reactive power; it uses only standard components connected in an original manner. The paper gives the results of EMTP simulations for the conditions governing the design of the components. The significant steady-state and transient capabilities of the components are given as well as insulation coordination and protection aspects. Finally, a preliminary layout is presented for the prototype. >

Steady-state analysis of power flow controllers using the power controller plane

This paper presents a new approach which simplifies the steady-state analysis and design of power flow controllers (PFC). The method is independent of the size and complexity of networks. It introduces the power controller plane where two families of nearly decoupled active power characteristics are defined as a function of the phase angle across the PFC: one for the network and the other for the PFC. Limiting cases of each families are used to define a working area which contains all the operating points of a given PFC and where its most stressing operating conditions can be readily identified. With this approach, only a few network cases are needed to perform steady-state PFC studies for both pre- and post-contingency conditions. Because the method looks at networks from the PFCs point of view, it simplifies contingency analysis, the design of PFCs and the definition of simple network equivalents suitable for active power flow studies.