Jacques Brochu

Model Validation for Wind Turbine Generator Models

This paper summarizes the work of the Ad Hoc Task Force on Wind Generation Model Validation. The paper describes the concept of model validation, how this applies to wind turbine generation systems, and then gives clear examples of the most recent efforts to achieve model validation for wind turbine power plants. The document ends with a summary of the learning from the work presented and the conclusions which can be derived. Recommendations are made on the path forward for wind turbine generator modeling and model validation, primarily focused on generic models (i.e., standardized and publicly available) for stability analysis in power system studies.

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). >

Validation of Single- and Multiple-Machine Equivalents for Modeling Wind Power Plants

This paper presents an exhaustive simulation study performed to validate the adequacy of the equivalencing method promoted by the National Renewable Energy Laboratory for modeling wind power plants by single- and multiple-machine equivalents. The main simulation results are presented for a number of steady state and transient wind turbine generator operating conditions following various faults and a typical low-voltage ride through. The impact of protection systems such as the crowbar is also taken into account. The aggregation technique has shown to be adequate for load flow, stability, and electromagnetic transient studies with limitations, as presented in the paper.

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. >

Generic Equivalent Collector System Parameters for Large Wind Power Plants

This paper provides a set of generic equivalent collector system (ECS) parameters for power system studies of large wind power plants (WPPs) represented by single-machine equivalents. They are intended to be used when actual collector system data are not available for calculating specific ECS parameters. The accuracy that can be expected with the generic ECS is quantified for a sample of 17 actual WPPs in the range of 50-300 MW. Generic ECS parameters have shown to provide active and reactive powers at the ECS output whose accuracies are adequate for prospective or preliminary studies.

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. >

On-Load Network De-Icer Specification for a Large Transmission Network

This paper presents a feasibility study conducted with a view to installing an on-load network de-icer (ONDI) for de-icing HV transmission lines forming part of the Matapedia subtransmission network operated by Hydro-Quebec. The ONDI concept makes use of a phase-shifting transformer (PST) to induce very large ac currents to heat line conductors by the joule effect. A single ONDI can handle a number of lines of different length with no need to transfer loads to other lines or disconnect them. In the study presented, more than 900 km of 230- and 315-kV HV circuits can be de-iced with one ONDI installed at Rimouski substation. To put the ONDI to work, only existing circuit breakers need to be operated so that no open-air (ice-sensitive) disconnecting switches are involved. The adequacy of this planning study is also discussed here with regard to taking into account uncertainties related to the weather conditions expected for severe ice storms.

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. >