Control of Rubber Tyred Gantry Crane with Energy Storage Based on Supercapacitor Bank

Abstract

This paper proposes a hybrid energy system, which consists of a diesel-engine generator and a supercapacitor, for improving performance of a Rubber Tyred Gantry Crane (RTGC). The supercapacitor contributes to the energy recovery associated with regenerative braking in 'Hoist-Down' braking operation and to the rapid energy consumption related with acceleration in 'Hoist-Up' operation of the RTGC. Hence it does save energy, which is conventionally wasted by a braking resistor. In addition, the large engine generator is replaced by the much smaller one, for the supercapacitor reduces high power demands away from it. For power conversion between the supercapacitor and the DC link, a 3 legs bidirectional DC-DC converter, which has the same structure as the commercially available 3-phase inverter, is used. Two kinds of simulations are performed to study the behaviors of the proposed system under the worst operating conditions. The performance of the proposed hybrid energy system is evaluated through several experiments with a real RTGC.

DC-bus power quality for aircraft power systems during generator fault conditions

“…A negative deviation in the DC-bus voltage, V bus , is apparent when the short-circuit is applied, Supercapacitor based energy storage is proposed for a variety of applications in published literature, often as a power buffer between the load and the main power source [9,[20][21][22][23][24][25][26][27][28][29]. The control schemes are often based on a power balance between the individual hardware elements that form the system [20][21][22][25][26][27][28].…”

“…A negative deviation in the DC-bus voltage, V bus , is apparent when the short-circuit is applied, Supercapacitor based energy storage is proposed for a variety of applications in published literature, often as a power buffer between the load and the main power source [9,[20][21][22][23][24][25][26][27][28][29]. The control schemes are often based on a power balance between the individual hardware elements that form the system [20][21][22][25][26][27][28]. These control schemes are inappropriate for this application, for example they are based on vehicle speed [22], committed power generation [20,26], generator speed-droop characteristic [27], estimated diesel engine output [25], or are designed to enable the main power source to have a constant output [21] or require many system level measurements [28] which if extrapolated to an aircraft system would be unmanageable and may introduce communication difficulties.…”

“…The control schemes are often based on a power balance between the individual hardware elements that form the system [20][21][22][25][26][27][28]. These control schemes are inappropriate for this application, for example they are based on vehicle speed [22], committed power generation [20,26], generator speed-droop characteristic [27], estimated diesel engine output [25], or are designed to enable the main power source to have a constant output [21] or require many system level measurements [28] which if extrapolated to an aircraft system would be unmanageable and may introduce communication difficulties. DC-bus voltage control schemes [23,24,29] for the energy storage device are not appropriate here as the bus voltage in this work is regulated by the two generator controllers.…”