Academic Writing: Paragraph

A paragraph - a group of related sentences that discuss mainly one idea. It

-        can be long enough;

-        the number of sentences is unimportant;

-        visually organized.

Parts of a paragraph:

•        The topic sentence        - states the main idea of the paragraph;

- names the topic;

- limits the topic to one specific area;

•        The controlling idea      - announces the specific area;

•        Supporting Sentences    - develop the topic sentence;

- explain or prove the topic sentence;

- give more information;

•        Concluding sentence     - signals the end of the paragraph;

- summarizes the paragraph. with important points to remember. (It can do this in two ways: by summarizing the main points of the paragraph or by repeating the topic sentence in different words);

- is needed only for stand-alone paragraph. 

 

Read this example of a paragraph:

Paragraph I: Challenges for existing adaptive approaches

The key challenges with existing AOCR schemes emerge with the upcoming DER interconnection requirements and transitioning/operating as microgrids. Addressing these will be formative for the development of more versatile AOCR schemes supporting grid/microgrid modes of operation.

A. Underreaching OCRs With Multiple DER Generation Levels

Considering DERs as constant current sources, existing AOCRs often downscale the DER fault current contribution for different levels of output w.r.t. rated power. However, DERs can feed maximum fault current even when producing low unfaulted output power because they behave like a terminal voltage controlled current source. depends on highly variable parameters like distance from the fault, fault impedance, and fault type. As a result, existing AOCRs may overcompensate DER output for lower output power and under-reach.

B. Delayed Trip Time for a Fault in the Primary Protection Zone

Microgrids can have significantly lower fault currents compared to grid-connected systems. This negatively affects the OCR sensitivity in primary/secondary zones. In the microgrid mode, traditional time-based coordination can cause a significant delay in a relay’s trip time for primary zone faults. Existing AOCR approaches do not discuss this problem.

C. Current Direction Reversal Due to the Mode Switching

Current direction reversal is possible for i) the grid-connected system given the DER output states, or ii) microgrids depending on the location of the grid forming DER. Existing AOCR approaches seldom discuss the directional aspects of protection. However, adapting directional supervision when available is important to ensure selectivity towards internal vs external faults. Without accounting for directional supervision, it is difficult to create a robust scheme for the coexistence of grid-connected and microgrid modes.

These observations show that the existing AOCRs lack applicability to ADNs with both grid and microgrid modes, are vulnerable to under-reaching and changing fault current, and can be too complex to implement in traditional distribution relays. The next section elaborates a new emerging vulnerability difficult to address with current practices to programming the relay.

 

Agree or disagree with the following points about paragraphs:

1).  A good topic sentence:

a) is a complete sentence with a subject, a verb, and a controlling idea;

b) states the main idea of the paragraph;

c) is neither too general nor too specific;

d) the controlling idea limits the topic to one specific area that can be discussed;

e) is usually the first sentence in the paragraph;

f) the helpful guide to both: the Writer and the Reader.

2. Good supporting sentences:

a)  develop the topic sentence (explain or prove the topic sentence by giving more information about it);

b)  are specific and factual;

c)  can be examples, statistics, or quotations.

3. A good concluding sentence:

a) signals the end of the paragraph and leaves the reader with important points to remember;

b) summarizes the important points briefly or restates the topic sentence in different.