快速公交系统（Bus Rapid Transit）作为一种介于轨道交通与常规交通之间的新型运营系统，它利用现代公交技术配合智能交通的运营管理，使传统的公交系统基本达到轨道交通的服务水平，而其投资及运营成本又较轨道交通低而与常规公交接近。
A well-known bus manufacturer in China successfully secured an order of one hundred 18-meter hybrid electric buses recently from a Karachi company. GTAKE, as a premium supplier of electric vehicle (EV) motor controller, supplied integrated solutions of EV motor controllers for this batch of buses.
These buses, powered by GTAKE controllers, will be operated in Karachi, the largest city of Pakistan, which further adds GTAKE's global presence in the field of EV motor controllers.
Karachi, the economic center of Pakistan, is a metropolitan with a population of 20 million. With such a large population base, the issues of road congestion and citizen travel demand are becoming more and more prominent, and there is an urgent need to establish a comprehensive network for public transportation. Two BRT special lines, the orange line and the green line, came into being in Karachi under this circumstance.
BRT ( Bus Rapid Transit), as a new operating system, uses modern bus technology with intelligent traffic management, enabling the traditional bus transportation system basically to reach the level of service of rail transportation, while its investment and operating costs are lower than rail transit and close to conventional buses. With the previous in-depth survey, the customer decided to adopt hybrid system solution for the buses. Models G03 and G04 motor controllers are utilized in the system, according to the proposal presented by GTAKE. The core components of the two controllers are from leading companies, not only guaranteeing the performance,
but also providing quick dynamic response for the operation. GTAKE persists in providing high-quality products by virtue of optimal software system, as well as automotive grade components to ensure safe operation of the vehicle, and provide a comfortable bus travel experience for passengers.
Based on the terrain characteristics of Karachi, this batch of electric buses select to adopt lightweight solution. The controller developed by GTAKE has the advantage of high space utilization, playing a significant role in reducing the weight of the vehicle.
·G03 external dimensions: 488mm × 244mm × 110mm; weight: 13.5kg
·G04 external dimensions: 600mm × 300mm × 142.8mm; weight: 22kg
The GTAKE controllers are able to meet the climbing demand easily. Under the constant power mode, the output torque can be maintained to be stable and sufficient. Through an optimized torque control tactic, the vehicle can run on slopes smoothly and stop comfortably without sliding backward.
·G03 rated voltage: 540V; rated power: 132 kW; peak power: 198 kW
·G04 rated voltage: 540V; rated power: 200 kW; peak power: 300 kW
Energy saving and environmental protection are regarded as two important indexes for a hybrid electric vehicle. During low-speed or decelerating driving, the controller can automatically recognize the operating status of the vehicle, and shift to the mode of electric power supply for the vehicle in order to reduce exhaust emissions. The G03 controller is equipped with the mechanism of energy recycling. It stores regenerating energy dynamically, and monitors the battery capacity at all times, ensuring the vehicle is always in a balanced status and increase the mileage remarkably.
Bus, as a way of transportation to serve the public, is endowed with properties of frequent-use, and prone to go through complex city roads and weather conditions. The safety of the vehicle system, therefore, must be treated as the paramount criterion. The models G03 and G04 motor controllers in the bus are programmed with all-round protections, such as quick protection on short-circuit, overcurrent, overvoltage, over-temperature, overload, encoder disconnection, etc., also their IP grade meets the standard IP67.
These hybrid electric buses are expected to run in Karachi Orange & Green BRT pass in the near future, a beautiful landscape of the city. It will bring convenient travels to local citizens, and significantly contribute to the environmental protection as well. It is also believed it will provide reproducible experience to more cities in Pakistan to carry out the settlement of BRT.